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Linux-driver development for components of the UAV-based

1. Figure 3 4 Connection between COM SC16IS740 chips and the corresponding devices Below it is explained how both protocols work and the specific configuration both chips need for having the wished behavior 3 1 1 PC C Inter Integrated Circuit is a serial computer bus invented by Phillips NXP 2012 The bus uses a bidirectional two wire connection consisting of the Serial Data Line SDA and the Serial Clock SCL A third line GND is also necessary but only for having the ground reference The bus connects two nodes the master and the slave The master device starts the data transmission generates the clock signal and chooses whether to read or to write the slave Each slave has an assigned 7 bits address this way a master can handle up to 128 slaves Any node can play the master role as long as the device supports this feature Common I C bus bit rates are 100 kbit s for standard mode and 10 kbit s for low speed mode When the master tries to write in a slave the communication has the following format S Slave address W ACK Reg address ACK DATA ACK P idle When the master reads the slave the format of the communication looks as follows Linux driver development for components of the UAV based fawn detection system 37 Carmen Eva Ballesteros Gonz lez I REPORT 2 3 DEVELOPMENT OF THE LINUX DRIVER S Slave address W
2. Linux driver development for components of the UAV based fawn detection system 29 Carmen Eva Ballesteros Gonz lez I REPORT amp 2 DEVELOPMENT OF THE TEST ENVIRONMENT File Options View Help Connect Port dev ttySO v R Baud 115200 Data 8 v Stop v Parity None v CTS Flow Rx 0 Reset Tx 0 Reset Count o 0 Reset Newline at None v El Show newline Clear received El Ascii Hex Dec Bin E Save output v O Clear at o F Ber 0 E E Autoscrol Sequence Overview amp m Received Data 1 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 Selection Input control Input options Clear transmitted E Ascii Hex Dec Bin Send on enter None v Type ASC y Transmitted data amp 1 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 History 0 10 Not connected Figure 2 6 HTerm 0 8 1 beta FLIR Systems has developed a software for controlling the camera from the PC connected through USB or RS 232 serial interface FLIR Camera Controller GUI SYSTEMS 2011 It was used to test the influence of different parameters in the resulting image Figure 2 7 shows the FLIR Camera Controller GUI with some features that can be set Once the more important parameters for the project are defined with the FLIR Camera Controller GUI they can be implemented by using HTerm see section 2 2 1 2 in order to try the special format of the commands accepted by the camera Further information about the
3. Product Company Units TAU640 FLIR Systems 1 MLR100 Aerius Photonics 1 MLR100 Interface Board Aerius Photonics 1 SC16IS740 NXP 2 Overo Sand COM Gumstix 1 1 2 Test environment Product Company Units ELV USB I2C ELV 1 TTL 232R PCB FTDI Chip 1 SC1615740 NXP 1 Monitor 1 1 3 Software Program Amount Hours of work project HTerm 1 150 C Kermit 1 260 Linux driver development for components of the UAV based fawn detection system 5 Carmen Eva Ballesteros Gonz lez DOCUMENT II PROJECT BUDGET 1 MEASUREMENTS 1 4 Equipment and tools Element Amount Hours of Hours of work project work year Computer 1 1000 1600 Oscilloscope 4 channels 1 10 300 Multimeter 1 20 300 Soldering iron 1 30 300 Solder sucker 1 15 150 1 5 Labor Activity Hours Initial tests 50 Programming 300 Hardware implementation 70 Tests and problem solving 150 Writing documentation 150 Total 720 Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez Chapter 2 Unit prices This chapter gathers the unit price of every product used during the project 2 1 Final product Product Price unit Shipping TAU640 11 999 99 MLR100 1 885 72 MLR100 Interface Board 381 68 SC16IS740 1 23 7 33 Overo Sand COM 86 92 2 2 Test environment Product Price unit Shipping ELV USB PC 24 95 4 95
4. 1 1 1 Motivation Every year circa 100 000 roe deer fawns are killed by the harvesting machines during mowing actions in Germany and a total of around 500 000 wild animals die every year in these conditions 1 It happens mostly between May and June coinciding the end of the growing seasons with the period when the baby deer are born The mother leaves the new born fawns in the high grass hidden from their natural predator while looking for food During the first three to eight weeks of life roe deer fawns face danger situations by remaining instinctively motionless on the ground The lack of motion their natural camouflage and their small size make their detection more difficult In order to locate those animals before the mowing the German Aerospace Center DLR through the Remote Sensing Technology Institute is developing several systems aimed to scan an area looking automatically for the fawns One of those methods consists in using an octocopter that flies over the field looking for those animals as Figure 1 5 shows Figure 1 5 Octocopter flying over a field Linux driver development for components of the UAV based fawn detection system XI Carmen Eva Ballesteros Gonzalez RESUMEN The octocopter carries several sensors and cameras on board The cameras are a thermal camera and a visible camera Both are connected to a Computer On Module that analyzes the images Once an animal is detected the computer sends the exact positi
5. SUCCESS read file answer BUF_LEN close file 3 3 Generic Terminal Driver for SC161S740 The aim of this driver is to act like a bridge between the user space and the UART port of the SC16IS740 In order to make possible to control the device from a terminal program it is necessary that the software contains a terminal driver This can be attempted by adding either a uart_driver or a tty_driver Tty drivers are responsible of providing an interface for terminal style devices as serial ports or some types of modems CORBET 1995 A uart_driver is a driver derived from tty with specific added features that optimizes the software for managing UART ports As seen before in 3 2 1 the software also needs an i2c_client and therefore an 12c_driver to use the SMBus functions from the 12c_core Furthermore it is recommended to develop a line discipline for the thermal camera which would translate the messages into the specific format Implementing all necessary features together in the same software seems easier using the tty_driver than the uart_driver as the device is not a pure UART port Figure 3 7 represents the interaction of the different layers The generic driver is confined as a module device driver and therefore it needs both module_init and module_exit functions that would be executed when the driver is load and unload into the kernel In module_init the terminal driver as well as the 12c_ driver needs to be r
6. do_ffe short FFC or a long one P on 0x0C 0x0 1 long factory reset Resets camera with factory header g 0x03 0x0 values Linux driver development for components of the UAV based fawn detection system 71 Carmen Eva Ballesteros Gonz lez II USER MANUAL 3 COMMANDS FOR THE TAU640 CAMERA Command Description Argument EC BC freestring Sends the argument command 6E00 iit_mean Sets the ITT midpoint offset 0 255 0x55 0x2 max_agc_gain Sets the max value of video gain 0 2048 Ox6A 0x2 plateu Specifies the Plateau level for Plateau AGC 0 1000 Ox3F 0x2 reset Reset to default modes 0x02 0x0 set_default Restore settings as power on values 0x01 0x0 spot_meter_mode Sets the spot meter mode on C scale off disable Ox1F 0x2 test_pattern Sets the test pattern mode test pattern off ascending ramp big vertical horizontal shade color bars ramp with steps 0x25 0x2 video_lut polarity Sets the analog video LUT or intensity transform white black fusion rainbow globow ironbow1 ironbow2 sepia colorl color2 ice_fire rain OEM red green 0x10 0x2 XP bus_mode Set the XP bus mode 0 Gen Bus 1 BT656 0x12 0x2 Table 3 1 Table with the available function commands in the application for the TAU640 camera As example changing the analog v
7. established that the address for the SC161S740 connected to the laser distance sensor is 1001 000 R W Therefore the address of the slave when the master writes is in hexadecimal 0x90 When using the SMBus functions 0x48 will be indicated as slave address Besides that the only difference in the configuration of the UART is the baud rate As it requires 19200 Bd it can be obtained using 6 as divisor and a prescaler of 1 Finally configuring all the required settings can be done with the following commands Linux driver development for components of the UAV based fawn detection system 42 Carmen Eva Ballesteros Gonz lez I REPORT 2 3 DEVELOPMENT OF THE LINUX DRIVER Start Bit Address Register Address Data Stop Bit S 90 18 80 P S 90 00 06 P S 90 08 00 P S 90 18 03 P S 90 10 06 P S 90 10 01 P 3 2 Development of the specific software for controlling both devices While developing a device driver it s important to make the distinction between user space and kernel space VENKATESWARAN 2005 Kernel space In Linux the machine s hardware is managed in an efficient manner offering the user a simple and uniform programming interface In the same way the kernel and in particular its device drivers form a bridge or interface between the end user programmer and the hardware Any subroutines or functions forming part of the kernel modules and device drivers for example are considered to be pa
8. OF THE TEST ENVIRONMENT Name Type Description GND GND Device ground supply pin CTS Input Clear to Send Control input Handshake signal VCC Output 5V output TXD Output Transmit Asynchronous Data output RXD Input Receive Asynchronous Data input RTS Output Request To Send Control Output Handshake signal Table 2 1 TTL 232R PCB Input Output Descriptions 1 Voo XTAL2 1 Vcc 2 A0 XTAL1 2 ay 3 Al RESET 3 4 n c SC1615740 RX 4 RX 5 SCL TX 5 Ars Di 6 SDA CTS 6 on ND 7 RO RTS Ta 8 12C Vss 8 CTS Figure 2 5 Connection lines only related with the UART of the circuit that connects the SC1615740 chip with a PC 2 2 Software tools Besides the hardware tools some software tools and a software environment see section 2 2 4 Cross Compilation were also used to check the behavior of the chip and the devices Communication software tools see section 2 2 1 were used to access and control the devices connected to the serial port from the PC as well as a special GUI application developed for controlling the thermal camera see section 2 2 2 These software tools and their applications are explained in this section 2 2 1 Communication tools There are some applications that allow a communication with devices connected through the serial port In this project two serial por
9. SC1615740 750 760 Single UART with I2C bus SPI interface 64 bytes of transmit and receive FIFOs IrDA SIR built in support NXP Semiconductors 3 Venkateswaran Sreekrishnan 2008 Essential linux device drivers Prentice Hall Linux driver development for components of the UAV based fawn detection system XV Carmen Eva Ballesteros Gonz lez RESUMEN Linux driver development for components of the UAV based fawn detection system XVI Carmen Eva Ballesteros Gonz lez Abstract Every year just in Germany around 100 000 roe deer fawns are killed by the harvesting machines during the mowing actions JARNEMO 2002 During the silage the carcasses of those animals is accidentally mixed with the crop and given as fodder for the dairy cattle producing them a paralytic illness This fact harms the agrarian sector by causing huge economical losses The German Aerospace Center DLR is developing several systems aimed to scan an area looking automatically for the fawns ISRAEL 2010a One of those methods is using an UAV unmanned aerial vehicle based system that carries a computer on module with several sensors including a thermal infrared camera aRGB camera and a laser distance sensor The main scope of this master thesis consists in developing the necessary drivers that enables the communication between the computer on module and 1 the thermal camera 2 the laser distance sensor The communication is not direct An interface t
10. TTL 232R PCB 15 15 17 25 SC16IS740 1 23 7 33 Monitor 50 00 2 3 Software Program Price unit HTerm 0 00 Freeware C Kermit 0 00 Freeware 2 4 Equipment and tools Element Price unit Computer 799 00 Oscilloscope 4 channels 1 580 00 Multimeter 45 00 Soldering iron 35 00 Solder sucker 35 00 Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez DOCUMENT II PROJECT BUDGET 2 UNIT PRICES 2 5 Labor Activity Price hour Initial tests 12 00 Programming 12 00 Hardware implementation 12 00 Tests and problem solving 12 00 Writing documentation 12 00 Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez Chapter 3 Partial summation This chapter gathers the partial costs of the elements conforming each entry that were calculated by the measurements and unit prices 3 1 Final product Product Units Price unit Shipping Total cost TAU640 1 11 999 99 11 999 99 MLR100 1 1 885 72 1 888 86 MLR 100 Interface Board 1 381 68 381 68 SC16IS740 2 1 23 7 33 2 46 Total 14 272 99 3 2 Testing environment Product Units Cost per unit Shipping Total cost ELV USB I2C 1 24 95 4 95 29 90 TTL 232R PCB 1 15 15 17 25 32 40 SC16IS740 1 1 23 7 33 8 56 Total 70 86 3 3 Software Product U
11. add the last bit depending if it is reading or writing static int scl6is740_probe struct i2c_client client const struct i2c_device_id xid struct i2c_board_info my_info struct i2c_adapter my_adap my_info kzalloc sizeof my_info GFP_KERNEL my_adap kzalloc sizeof my_adap GFP_KERNEL Linux driver development for components of the UAV based fawn detection system 45 Carmen Eva Ballesteros Gonz lez I REPORT amp 3 DEVELOPMENT OF THE LINUX DRIVER my_adap gt nr BUS_NUMBER my_adap gt id BUS_NUMBER strncpy my_info gt type DEVICE_NAME sizeof my_info gt type my_info gt addr ADDRESS_KAM my_sc161s740 gt client i2c_new_device my_adap my_info return SUCCESS The attach_adapter function is called when a new bus is loaded to the system and checks to see if any I2C device is on this I2C bus to which the client driver wants to attach In this case it calls the detect function static int scl6is740_attach struct i2c_adapter adapter return scl6is740_detect_client adapter ADDRESS_KAM 0 a The detect_client function probes the given address and fulfills the 12c_client data static int scl6is740_detect_client struct i2c_adapter xadapter int address int kind my_sc161s740 gt client gt driver amp my_driver my_sc161s740 gt client gt addr address my_sc161s740 gt client gt adapter ada
12. an order It consists in sending to the application as first argument the first part of the command up to CRC1 and as second argument the data again without the CRC2 code The application generates both omitted CRC codes and sends the command to the camera The purpose of this option is to let the sending of commands that are not implemented in the program exempting the user from calculating both CRC Text in bold in table 3 1 represents the recognized arguments by the application It is remarkable the special case of the function freestring that sends as direct order the following argument A correct order using this function is root overo configtau640 freestring 6e0000140002605200642c22 Command Description Argument re BC agc_filter Sets the AGC ITT filter value 0 255 0x3E 0x2 plateu once bright agc_type Sets the image optimation mode auto bright 0x13 0x2 manual linear brightness Sets the manual brightness value 0 16383 0x15 0x2 braeht ess bins oO aan 9048 0x15 0x2 auto bright mode contrast Sets the manual contrast value 0 255 0x14 0x2 dde_gain Sets the gain of the DDE filter 0 255 0x2C 0x2 dde_threshold Sets the threshold of the DDE filter 0 255 OxE2 0x2 0 14 bit data 1 8 bit data 2 digital off digital_output Sets the digital output channel mode 3 14 bit unfiltered 0x12 0x2 4 8 bit inverted 5 14 bit inverted 6 14 bit inv unfilt
13. be easily distinguished from ground and therefore detected Direction of motion Radar sensors Reflexion of the I 1 ground Antenna I i i b Ba y u l k J Reflected from A gt target figure N N Volume variation K of i vegetation MN I 1 11 Vegetation Figure 1 5 Principle of the double radar Source A FACKELMEIER 2009 ll 10001 4 F Another possibility is to assemble the sensors directly on the mowing machine with a front facing orientation looking at the current swath The geometrical problem explained in the Trailing with dogs section would be also applied here reaching the conclusion that placing infrared sensors is more effective than a camera system in order to detect a fawn lying on the ground UAV based system The last method consists in using an UAV unmanned aerial vehicle based system that carries a computer on module with several sensors The main sensors of the measurement hardware on board are a thermal infrared camera and a camera for the visible region Under certain weather conditions it is difficult to distinguish in the infrared image an animal from something else that reflects the solar light The visible camera is used to compare both images in order to make the detection more precise The cruising altitude can be chosen between 30 meters and 50 meters As Fig 1 6 shows at an altitude of 50 meters the image
14. hand the struct file_operations is typically used to manipulate files As in UNIX or Linux systems the devices are seen as files that can be open closed written and read it will be used in this case to manipulate the device On the other hand it is needed an 12c_ client to hold the information of the i c device The kernel already provides some tools collected in the i2c_core to use the i c port and by adding an i2c_driver with probe and detach functions to bind and unbind the device the communication through the 12c port will be easily attained Therefore it 1s necessary to attach the file_operations to the character device and to register an i2c_driver in the 12c_core 3 The developed driver is inserted with the kernel using the command insmod It executes the function of the module driver called module_init The task of this function is to register the char_driver with the kernel and the i2c_driver in the 12c_core The driver can also be deleted from the kernel using rmmod which executes the function module_exit of the module driver Once the i2c_driver is registered in the 12c core it executes certain functions called probe attach_device and detect_client The driver collects information about the I2C bus and the address of the PC slave together into the struct i2c_client The character driver provides the struct file_operations with functions as open close write and read that can be used by the applications in user
15. in the range between 1 and 2 1 Setting a bit in a register prescaler gives also the possibility of dividing the divisor by 4 The equation 3 1 shows how to calculate the divisor for the desired baud rate and in table 3 3 the required divisors are already calculated for the most common baud rates including the percent error difference with the actual baud rate considering the 1 8432 MHz crystal integrated in the EB as clock input XTALlcrystalinput frequency prescaler divisor 3 1 desiredbaudrate 16 ey Let s start with the requirements from the serial port in the thermal camera Baud rate 57600 Data bits 8 Linux driver development for components of the UAV based fawn detection system 40 Carmen Eva Ballesteros Gonz lez I REPORT 3 DEVELOPMENT OF THE LINUX DRIVER Desired baud rate Divisor used to Percent error difference generate 16 clock between desired and actual 50 2304 0 75 1536 0 110 1047 0 026 134 5 857 0 058 150 768 0 300 384 0 600 192 0 1200 96 0 1800 64 0 2000 58 0 69 2400 48 0 3600 32 0 4800 24 0 7200 16 0 9600 12 0 19200 6 0 38400 3 0 56000 2 2 86 Table 3 3 Baud rates of the SC1615740 using a 1 8432 MHz crystal SC1 2011 Parity None Stop bits a Flow control None Using the programmable baud rate generator to obtain the desired baud rate of 57600 Bd for the thermal camera s port a divisor with value 2 is req
16. it was necessary to develop an expansion board EB The task was carried out during a previous master thesis NEUGEBAUER 2011 For its design several factors had been considered From the structural side the optimization resides in the minimum weight and size as well as an optimal physical distribution of the components all along the expansion board Because of the different specifications of the elements in the EB and the other hardware components it was also necessary to implement level shifters inverters and converters Another important factor in the design is the power supply The required voltage changes from one element to another making it necessary the existence of 1 8V 3 3V and 5V sources The EB is fed with a voltage supply of 5V Internal voltage converters provide the remaining 3 3V and 1 8V In the octocopter the power supply comes from a lithium polymer battery Figure 1 10 shows the block diagram of the EB An overall front and back picture with the components assembled is shown in figure 1 11 Linux driver development for components of the UAV based fawn detection system 20 Carmen Eva Ballesteros Gonz lez I REPORT e 1 INTRODUCTION IR Camera UARTiinv Digital video Invert Level Shifter 7 fuser Digita 12C e UART Video PC Console UA
17. mortality rates and countermeasures KURT 1968 KURT F 1968 Das Sozialverhalten des Rehes Capreolus capreolus L MUERI 1999 MUERI H 1999 Witterung Fortpflanzungsgeschehen und Bestandesdichte beim Reh Capreolus capreolus L 45 ed NEUGEBAUER 2011 NEUGEBAUER PHILIPP 2011 Entwicklung eines Gumstix Expansion Boards fuer ein UAV basiertes Rehkitzrettungssystem Master s thesis Hochschule Osnabrueck NXP 2012 NXP 2012 UM10204 I2C bus specification and user manual http www nxp com documents user_manual UM10204 pdf OSBORNE 1980 OSBORNE ADAM 1980 An Introduction to Microcomputers Volume 1 Basic Concepts Osborne McGraw Hill Berkeley California USA SYSTEMS 2011 SYSTEMS FLIR COMMERCIAL 2011 FLIR Camera Controller GUI http www flir com cvs cores resources software tau VENKATESWARAN 2005 VENKATESWARAN SREEKRISHNAN 2005 Writing a Kernel Lime Discipline Linux Magazine http www freesoftwaremagazine com articles drivers_linux VENKATESWARAN 2008 VENKATESWARAN SREEKRISHNAN 2008 Essential linux device drivers Prentice Hall Linux driver development for components of the UAV based fawn detection system 64 Carmen Eva Ballesteros Gonz lez PART II USER MANUAL Chapter 1 How to configure the settings of the serial port in the driver In the driver in kernel space the only part of the code that depends on the attached device
18. output of the camera and checking that the entered commands actually change the image in an expected way Figure 1 8 helps to visualize the difference between three different contrast values in the image captured by the camera and the following code is an example of setting the contrast with the value 100 root overo configtau640 contrast 100 Sent 6e 0 014 0 2605a 0642c22 Answer 6e 0 014 0 2605a 0642c22 Linux driver development for components of the UAV based fawn detection system XIV Carmen Eva Ballesteros Gonzalez RESUMEN Figure 1 8 From left to right captured images with contrast 20 50 and 70 The application for the laser distance sensor was tested by taking measurements with the sensor connected to the Computer On Module All the tests resulted satisfactory proving that the application works correctly The following code is an example of the application taking measurements root overo mlr100 g 2 04m 1 4 Conclusions Aim of the thesis was to developed the required software for controlling the thermal camera and laser distance sensor at the octocopter The mentioned aim was full filled developing a driver that controls the communication with the device and a personalized application for eah device that interacts with the user and manages the developed driver Bibliography 1 Jarnemo A 2002 Wildlife Biology vol 8 Roe deer Capreolus capreolus fawns and mowing mortality rates and countermeasures 2
19. reception flow through two separate ways TX and RX Although the signal is usually carried by an electrical wire some signaling schemes might also be accomplished using bluetooth IrDA optical fiber As the transmission is asynchronous there is no clock signal sent with the other data Both UARTs must be configured with the same settings to be able to make a successful communication between them Those settings are the baud rate amount of bits that compose a word from 3 to 9 bits parity even odd or none number of stop bits 1 1 5 or 2 and optional flow control UART defines the communication protocol but the voltage signaling depends on the variant used Some examples are RS 232 RS 422 and RS 485 RS 232 is commonly used in desktop computers referred as COM port The variant supported by SC1615740 is RS 485 This standard admits voltage levels from 7 V to 12 V Positive voltages higher than 200 mV are considered logic 1 and negative voltages lower than 200 mV are considered logic 0 3 1 3 UART configuration for the SC1615740 The SC16IS740 gives enough options in setting the configuration for the UART port Baud rate Programmable baud rate a Data bits 5 bit 6 bit 7 bit or 8 bit character Parity Even odd or no parity Stop bits 1 1 5 or 2 Flow control Optional software and hardware flow control The SC161S740 contains a programmable baud rate generator that takes any clock input and divides it by a divisor
20. space Those functions must be however defined in kernel space In open the driver configures the serial port of the UART 4 C interface in accordance with the serial port of the attached device The open function as well as write and read use the struct i2c_client and the functions provided by the 12c_core in order to establish the communication through the 12c port Figure 1 7 shows the interaction between the relevant structs of the developed software 1 2 2 Development of the applications for user space Although a personalized application was developed for each device both contain the same structure First the application creates a valid message for the device Later the functions open write and read are respectively used for configuring the interface send the message and read the answer The answer is analyzed and in case of detecting an error the message is sent again to the device a maximal of three times The result as well as the possible error are reported to Linux driver development for components of the UAV based fawn detection system XIII Carmen Eva Ballesteros Gonz lez RESUMEN USER SPACE Baer KERNEL SPACE module_init register_chardev SMBus functions HARDWARE Figure 1 7 Diagram of the interaction between relevant structs in the developed module driver the user Before closing the application the function close belonging to the module driver
21. system 73 Carmen Eva Ballesteros Gonz lez DOCUMENT II PROJECT BUDGET DOCUMENT II PROJECT BUDGET INDEX Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez Index 1 Measurements Lal ia TORCER e 1 2 SN 1 35 DOH Waren a fetid a ta A A o el 1 4 Equipientand DOS ek wi a wa de a is a e a a 1 53 ALADO it werte A AA TAR NA e da e 2 Unit prices 2 Pal product 2 ar A EA 2 2 A EI 2 3 ION E A A ABS SA A AP ARA AR AA A 2 4 Equipment and tools ios bec hee ee Se ee be in da 2 3 Labor iu ke o Oe OE SOR SOK SEE Sh EE EE EE 3 Partial summation 351 Final product a Syed ey a Tu AR a ee SY BS 3 2 Testing environment AA A A A dd be Sede amp DIE a nS gh athe ty ghee GRP ak at a NP ate ee oh en ae hee ae hea ge hed E Bosipment and tools stas a a Data a Sa oOo a as 9 9 Babor ta na era gee ede PET PEO e Bo el de ed Dy ot dl 4 General budget oOOCOVOOOS AANANINAINAIN NA Uu a Uan y a A jun Linux driver development for components of the UAV based fawn detection system 3 Carmen Eva Ballesteros Gonz lez DOCUMENT II PROJECT BUDGET INDEX Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez Chapter 1 Measurements This chapter gathers a list of components and equipment used during the project as well as the attributable hours to the project 1 1 Final product
22. to connect both ports UART and IPC to a PC using on one side a UART USB and on the other side a USB I2C converter as shown in figure 2 1 A terminal program executed in the computer can be used to send commands through one port and read the converted output by checking the other port The chosen terminal program for the test is HTerm It is important to check that the output data is correct before further tests in this environment are done Linux driver development for components of the UAV based fawn detection system 25 Carmen Eva Ballesteros Gonz lez I REPORT 2 DEVELOPMENT OF THE TEST ENVIRONMENT USB I C USB C SC161S740 UART Figure 2 1 SC1615740 connected to a PC using both USB I2C and UART USB converter 2 1 1 USB I2C converter In order to test the chip it is necessary to connect the I C port of the SC1618740 to a PC The USB I2C converter developed by ELV Fig 2 2 was used for this purpose The converter is provided with three I C Bus including a 5V source and a USB port Each I C Bus contains a clock signal SCL a line to send data through SDA and ground GND More information about the I C protocol and the signals it requires can be found in section 3 1 1 Figure 2 2 ELV USB I2C Source ELV 2010 As the I C port at the USB I2C works at 5 V and the SC16IS740 can only work with 3 3 V or 2 5 V a level shifter between them is needed The PCA9517 PCA 2007 is a level translating I
23. tool for executing tasks and managing metadata This directory contains the BitBake tool and its associated configuration files build The build directory contains configuration data for the build system The configuration is split between three files all of them in build conf auto conf local conf and site conf auto conf is used primarily to specify what machine configuration the build is targeted toward local conf is used to specify build policy uclibc vs glibc debug vs release etc site conf is used for general configuration location of source code cache location of temporary file directory environment set up parallel make etc Linux driver development for components of the UAV based fawn detection system 32 Carmen Eva Ballesteros Gonz lez I REPORT amp 2 DEVELOPMENT OF THE TEST ENVIRONMENT user collection This is the directory were the custom recipes should be placed BitBake gives highest preference to the recipes in this directory making it possible to override any functionality without having to touch directories under Gumstix source code control tmp This is where the build system keeps its working files and also where it places the output of the build From all the directories that it contains it is worth pointing out sysroot Inside tmp sysroot there are the cross development tools for generating code for the Gumstix processor compilers linkers etc Some necessary paths must be defined in Makefile for
24. work in slave mode This means the Gumstix system must play the master role and also that therefore the I C interface of the SC16IS740 chip needs an address The address can be selected using the pins AO and Al Fig 3 3 Usually with two bits the options are reduced to four possible states The SC1615740 chip allows up to 16 addresses using four possible values for each pin Table 3 1 shows the different combinations depending of the voltage values at pins AO and Al The chosen addresses for both SC16IS740 in the EB are AT A6 A5 A4 A3 A2 Al AO Laser distance sensor 1 0 0 1 0 0 O R W Thermal camera 1 0 0 1 0 0 1 R W where A7 A0 represents the bits of the address from MSB to LSB and R W distinguish if the order is for reading or writing taking the value 1 or O respectively After selecting the address the master also has to choose the register it is going to interact with Table 3 2 shows how the address for the registers is built In SC1615740 the internal register has a 4 bits ID A 3 0 In Section 3 1 3 there are shown the address of the principal registers and those that need to be configured to make the interface work in the wished way Linux driver development for components of the UAV based fawn detection system 38 Carmen Eva Ballesteros Gonz lez I REPORT 2 3 DEVELOPMENT OF THE LINUX DRIVER Al AO SC16IS740 I2C addresses hex VDD VDD 0x90 1001 000X VDD VSS 0x92 1001 001X VDD SCL 0x94 1001 01
25. 0 8 V and high logic for higher than 2 1 Volts V pp ranges from 3 to 5 Volts The clock frequency range of SMBus is from 10 kHz to 100 kHz interval that PC already covers SMBus also has a low time out limit defined at 35ms that I C doesn t own The protocol used in both interfaces is quite similar Actually the Linux Kernel not only has already implemented the necessary functions to manage the transaction through SMBus but also the functions for I C are derived from those ones SC16IS740 is compatible with SMBus specifications and therefore SMBus functions can also be used on it Linux driver development for components of the UAV based fawn detection system 39 Carmen Eva Ballesteros Gonz lez I REPORT 3 DEVELOPMENT OF THE LINUX DRIVER 3 1 2 UART The Universal Asynchronous Receiver Transmitter UART is a standard for serial communication The UART transmitter takes bytes of data and sends them bit to bit in a sequential fashion OSBORNE 1980 On the other node lies another UART collecting those bits to re assemble them into complete bytes The transmission has a specific format It starts with a start bit signal at low logic followed by a data block This block can contain from 5 to 9 bits depending of the configuration Optionally it can be followed by a parity bit for detection of possible transmission errors Finally a high logic stop bit signal indicates the end of the block and a new one might be send Transmission and
26. 0 and a PC Stop bits 1 Flow control None Transmitted characters must be followed with CR in hexadecimal 0x0D All answers ended with LF in hexadecimal 0x0A This is important for establishing the correct format of the sent and received data while programming the application 2 2 4 Cross Compiler A Cross Compiler is a compiler that creates executable code for another platform different from the one where the code is compiled So it makes possible to develop software for an embedded system using a personal computer In the case of the Gumstix Overo Series the Linux OpenEmbedded OE provides a build system It contains a collection of BitBake recipes These recipes contain the source URL of the package dependencies and compile and install options OE uses the information in these recipes to track dependencies cross compile the package and create binary packages It will also create complete images including boot loaders kernel and root file system As a first step the framework will build a cross compiler toolchain for the target platform Once the build environment is set the directories are structured in a specific way gumstix oe bitbake build org openembedded snapshot com gumstix collection user collection extras tmp From all the directories only the most relevant ones for the development of the software are below explained GUMSTIX 2011b bitbake OpenEmbedded is based upon BitBake a
27. 0X VDD SDA 0x96 1001 011X VSS VDD 0x98 1001 100X VSS VSS 0x9A 1001 101X VSS SCL 0x9C 1001 110X VSS SDA 0x9E 1001 111X SCL VDD 0xA0 1010 000X SCL VSS 0xA2 1010 001X SCL SCL 0xA4 1010 010X SCL SDA 0xA6 1010 011X SDA VDD 0xA8 1010 100X SDA VSS OxAA 1010 101X SDA SCL OxAC 1010 110X SDA SDA OxAE 1010 111X 1 X logic O for write cycle X logic 1 for read cycle Table 3 1 SC1615740 address map SC1 2011 Bit Name Function 7 not used 6 3 A 3 0 UART s internal register select 2 1 CH1 CHO channel select CH1 0 CHO 0 Other values are reserved and should not be used 0 not used Table 3 2 SC16IS740 register address byte SC1 2011 SMBus SMBus abbreviated form of System Management Bus is a two wire bus interface through which various system component chips can communicate with each other and with the rest of the system It is based on the principles of operation of I C and was defined by Intel Corporation in 1995 SMB 2000 After seeing IC it is more clarifying to explain SMBus by highlighting the differences between both interfaces Remarkable differences from the electrical side are the voltage level and the supported frequency Since in C the voltage specifications for low and high logic may vary in SMBus they are more fixed SMBus defines low logic as voltages lower than
28. 2 overo login root root overo insmod tau640 ko Kernelmodul ist gestartet Major Nummer ist 250 Um mit dem Treiber zu kommunizieren muss ein Device File mit mknod dev tau640 c 250 0 angelegt werden Driver registered root overo mknod dev tau640 c 250 0 A root overo Figure 4 1 Loading the Gumstix Overo System Thermal camera Figure Name Functionality 4 3 Video Connector Thermal Camera actual connector for TAU640 4 3 Analog Video Output Thermal Camera two pin connector in parallel to the analog video sent from the camera 4 2 UART Interface IR Camera extra UART connector for the configuration The slots corresponding to the laser distance sensor are Laser distance sensor Figure Name Functionality 4 2 RS232 Interface LDS actual connector for MLR100 4 3 LDS soldered connection extra UART connector Example of a performed test Scope Verify that the I2C master sends data to the I2C slave Procedure Measure the signal at the pin 6 SDA of the SC16IS740 Results Figure 4 4 shows a measure taken at that pin while receiving data from the computer through the I2C Bus 4 1 2 Tests connecting the EB to the computer Once the driver in kernel space is checked the application must also be tested In order to perform a more effective debug the preliminary tests are run connecting the EB to the PC instead of connecting it directly to the device A terminal program like Hterm see sectio
29. 2005 To register it as a module it is necessary to add in the module_init the function tty_register_Idisc N_TTY amp tty_ldisc_N_TTY Changing the line discipline from the user space can be done by indicating the number associated to the line discipline in the function ioct1 from the device driver Linux driver development for components of the UAV based fawn detection system 52 Carmen Eva Ballesteros Gonz lez Chapter 4 Results In order to ensure the correct development of software different test procedures were applied during the different development phases In the early phases of the project tests were applied by using an oscilloscope in other to check the existence of signals section 4 1 1 In the next step EB was connected to a Computer in order to read and test the outputs section 4 1 2 Once the satisfactory results were reached the tests were run with the actual devices connected to the EB In the particular case of the thermal camera a monitor was also connected in order to show in real time the captured image and therefore to be able to observe the changes in the pictures while introducing certain commands section 4 2 4 1 Preliminary tests There are different ways to read the messages sent through the SC16IS740 One possibility consists in measuring the voltage in certain pins and connection lines in the hardware Another more comfortable possibility is to connect the UART to a computer and with help of the H
30. 3 2 1 explains when using the SMBus functions the given slave address must have the LSB bit the one corresponding to R W omitted The used function will add itself the R or W bit depending if it is a reading or a writing function Therefore while programming the given slave address for the thermal camera is 0x49 instead of 0x92 Start Bit Slave address Register Address Data Stop Bit S 92 18 80 P S 92 00 02 P S 92 08 00 P Word length parity and the amount of stop bits are configurable in the register LCR According to the requirements from the UART in the thermal camera the configuration finally must be done sending the following command Start Bit Address Register Address Data Stop Bit s 2 18 Pos P The last remaining requirement is resetting the Tx and Rx FIFO and afterward enabling it FIFO mode This is done by setting at high logic the bits 1 and 2 of the register FCR with id 0x2 and therefore according to table 3 4 register address 0x10 Enabling the FIFO is done by setting at high logic the bit O of the same register This ends up with Start Bit Address Register Address Data Stop Bit S 92 10 06 P S 92 10 01 P The port settings for the LDS MER 100 are very similar to those for the thermal camera Baud rate 19200 Data bits 8 Parity None Stop bits 1 Flow control None As happened with the converter chip connected to the thermal camera in section 3 1 1 1t was
31. 7600 d 8 s 1 p None Figure 4 5 Hterm and a terminal 4 2 Test connecting EB to the actual devices Once it is confirmed that the commands are sent in the correct format and the application can read the given answers the tests with the corresponding devices already connected will be prosecuted The EB is already equipped with suitable slots to directly connect the device without adding any other adapter In order to prove the effectiveness of the application for the thermal camera a screen connected to the analog video output helps to visualize the changes in the captured image when adjusting the parameters of the camera Linux driver development for components of the UAV based fawn detection system 56 Carmen Eva Ballesteros Gonz lez I REPORT 4 RESULTS In the specific case of the laser distance sensor the aim is to obtain information not to change any parameter from the sensor The best way of checking the application resides in debugging from the software itself and checking if the received data is correct Because of the similarity of both drivers in kernel space and the greater complexity of the application for the TAU640 compared to the one for the MLR100 the tests were emphasized in the connectors of the TAU640 side The following section shows an example of how the tests were realized and how it works 4 2 1 Test connecting EB to TAU640 As explained in section 1 4 the aim of the application for the thermal camera
32. ACK Reg address ACK S Slave address R ACK DATA ACK NACK P idle The colored messages are the ones sent by the slave the other ones are sent by the master The meaning of the different messages and segments are explained in the following lines S Start bit it indicates that the master starts the communication by pulling SDA low while SCL remains at high level In consequence slaves get ready and wait for the beginning of the transaction Slave address 7 bit address A7 A1 of the slave sent from MSB to LSB W Occupies the position AO When the master is trying to write it takes the value 0 R Occupies the position AO When the master is trying to read it takes the value 1 ACK Acknowledge bit confirms the reception of data The receiver transmits a single 0 bit a NACK Negatively acknowledge bit indicates either there was an error during the reception or the master wants to finish the transmission The receiver transmits a single 1 bit Register address 8 bit address that indicates to the slave to which register the master wants to access Data Data is sent in an 8 bit format P Stop bit the master indicates the end of the communication by pulling SDA at high logic level while SCL remains at high level idle Both SDA and SCL are at logic high and any device can act as master In SC16IS740 the I C bus interface can only
33. C bus repeater that provides level shifting between low voltage 0 9 V to 5 5 V and higher voltage 2 7 V to 5 5 V for I C bus applications The pin configuration in Figure 2 3 shows both I C bus sides with the corresponding SCL and SDA of each side a ground GND pin and it provides also an enable EN pin The purpose Shttp www elv de output controller aspx cid 74 amp detail 10 amp detail2 24012 Linux driver development for components of the UAV based fawn detection system 26 Carmen Eva Ballesteros Gonz lez I REPORT amp 2 DEVELOPMENT OF THE TEST ENVIRONMENT of the EN pin is to enable the repeater when it is connected to the same voltage level than Voc The lower voltage I C bus is represented as the A side and the higher one as the B side Vecal Q 8 VccB SCLA 2 PCA9517 7 SCLB SDAA 3 6 SDAB GND 4 5 EN Figure 2 3 Pin configuration of the PCA9517 As the EN pin must be connected to a voltage supplier from the B side it was decided to set the SC161S740 at the B side and therefore the ELV USB I2C to the A side of the level shifter It was also necessary to add pull up resistors 10 kQ each on the B side In Figure 2 4 are only shown the connection lines related with the I C port O Von O
34. Death an 17 1 7 The flight plan of the UAV is designed to fly always at the same altitude taking as reference the start position In sloping terrains this affects to the image processing as the scale changes Source ISRAEL 201la 18 1 8 Falcon 8 model flying over a field Source ISRAEL 2011b 18 1 9 Gumstix Overo COM Source www gumstix com 22 2 2 nen 19 1 10 Block diagram of the Expansion Board 2 2 o rn 21 1 11 Front and back picture of the EB with all components assembled Source NEUGEBAUER 2011 ana a aa de a Geta ee ad 21 1 12 Connection between the COM and both the thermal camera and the laser distance SEAS A Se Gy ae Me 23 2 1 SC1615740 connected to a PC using both USB I2C and UART USB converter 26 2 2 ELV USB I2C Source ELV 2010 26 2 3 Pin configuration of the PCA9517 2 un 2a ee ee a a 27 2 4 Connection lines only related with the I C port of the circuit that connects the SC16IS740 chip with a PC ooo ios 222 a a a de 27 2 5 Connection lines only related with the UART of the circuit that connects the SC16IS740 chip witha PES N Mr ara a 28 2 6 Hicimos l beta zs ani pa AU O dans ee oe 30 2 7 Setup Tab and AGC Tab of the FLIR Camera Controller GUI Source Tau October 2010 31 2 8 Interface Adapter Board of the MLR100 sensor with the pins from the UART numbered ipet a e A wre eS 31 3 1 Interaction layers between user and hard
35. Document Index DOCUMENT I REPORT Part I Report page 11 to 64 Part II User Manual page 65 to 73 DOCUMENT II PROJECT BUDGET 1 Measurements page5 to 6 2 Unit prices page 7 to 8 3 Partial summation page 9 to 10 4 General budget page 11 to 11 55 pages 9 pages 2 pages 2 pages 2 pages 1 page Autorizada la entrega del proyecto del alumno Carmen Eva Ballesteros Gonz lez EL DIRECTOR DEL PROYECTO Martin Israel V B DEL COORDINADOR DE PROYECTOS lvaro S nchez Miralles UNIVERSIDAD PONTIFICIA COMILLAS ESCUELA T CNICA SUPERIOR DE INGENIER A ICAD INGENIERO INDUSTRIAL PROYECTO FIN DE CARRERA LINUX DRIVER DEVELOPMENT FOR COMPONENTS OF THE UAV BASED FAWN DETECTION SYSTEM AUTOR Carmen Eva Ballesteros Gonz lez DIRECTOR Martin Israel MADRID Abril de 2012 Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez IV Resumen 1 1 Introducci n 1 1 1 Motivaci n Cada a o mueren s lamente en Alemania unos 100 000 cervatillos reci n nacidos y alrededor de 500 000 animales salvajes incluyendo conejos zorros e incluso p jaros 1 Estos hechos suceden entre mayo y junio coincidiendo la poca de cosecha con el nacimiento de las nuevas cr as Durante las primeras semanas de vida las madres dejan a las cr as en los campos escondidas entre la hierba alta mientras van a buscar comida Los cervatillos reaccionan instit
36. Figure 1 12 marks the relevant hardware for the task Therefore the software must be executed in the Gumstix System that uses the Linux Kernel and it must be capable of communicating with the SC16IS740 through the I C bus configuring the serial port of the chip and establishing a communication with the attached device Before developing the software some preliminary work is necessary First of all it is recommended to test the SC161S740 interface alone This task is achieved by connecting both sides of the interface to a computer Besides there is also a software environment and some tools required for the development of software for the Gumstix System The necessary software and hardware to achieve the test as well as the software tools required to later develop the software are explained in Chapter 2 The next step is developing the software In monolithic kernels as Linux the kernel runs in kernel mode and the applications in user mode Therefore it has been established that the software will be split in two parts a driver in the kernel space to control the device It controls the communication with the hardware and configures the port setting of the UART at the SC16IS740 an application in the user space to interact with the user It is personalized for each device The information of how the software is developed remains in Chapter 3 The obtained results are explained in Chapter 4 User manuals for the drivers and applications develop
37. INUX DRIVER detach_adapter scl6is740_detach hi static struct file_operations my_fops open my_open release my_release read my_read write my_write y static int _ init scl6is740_init void My_Data kzalloc BUF_LEN GFP_KERNEL if My_Data return ENOMEM Major register_chrdev 0 DEVICE_NAME amp my_fops if i2c_add_driver amp my_driver printk KERN_ALERT Registering I2C driver failed static void __exit scl6is740_exit void unregister_chrdev Major DEVICE_NAME if My_Data kfree My_Data module_init sc161s740_init module _exit sc161s740_exit ct ct On the side of the i2c_driver after its implementation all clients are instantiated from it There are some important functions of the driver that must be particularly defined The probe function is called when an entry in the id_table name field matches the device s name It receives the matched entry and instantiate that device by filling an 12c_adapter structure with the bus number that is known in this case and an i2c_board_info structure with the device address and driver name Then it calls i2c_new_device this way the device will work with the new style i2c driver In my_info gt addr ADDRESS_KAM the address must contain the bits A 7 1 The LSB corresponding to R W is omitted because the functions from the i2c_core already
38. NTRODUCTION Parameter Value Baud rate 57600 Data bits 8 Parity None Stop bits 1 Flow control None Table 1 1 Port settings of the RS 232 serial interface of the camera TAU 640 3 RGB camera It is also necessary to add a RGB camera to the octocopter in order to collect color pictures to contrast them with the infrared ones The choice is a 5 megapixels camera e CAM50_OMAP_GSTIX from e con Systems specifically developed and built for the COM of the Gumstix s Overo Series The configuration is done through an I C interface and as happens with the thermal camera the video data travels through the 27 pin Flat Flex Cable FFC connection In order to let both thermal camera and RGB camera use the FFC a 2 1 multiplexer controlled by the COM will choose which data the Gumstix system will receive and analyze 4 Laser distance sensor The laser distance sensor LDS will be used to measure the height at which the octocopter is flying in order to verify the accuracy of the Google Maps Elevation API The chosen sensor is the model MLR100 developed by Aerius Photonics LLC It has a long range capability from 0 m to 100 m with a resolution better than 20 cm The LDS is connected through a RS 232 serial interface to the I C Bus from the COM In order to make this connection capable a UART I C converter SC1618740 will be used 5 Expansion Board In order to connect the COM with the remaining hardware components
39. RT pc Port BUS Level La js Computer On Module Shifter pre Host GPIOs PC 12C e UART av FN TV Out UART Gpios EEPROM Power Level VART Supply Shifter RS232 Back Tranceiver AR VART LED Taster Battery gt Haste RS232 y Falcon 8 LDS Connector Figure 1 10 Block diagram of the Expansion Board Figure 1 11 Front and back picture of the EB with all components assembled Source NEUGEBAUER 2011 1 3 3 Software The Gumstix Overo Series uses the Linux Kernel Image 2 6 34 and provides a software bundle and a base system out of the box i e it doesn t require any additional installation It also utilizes a build environment with cross compilation support called Linux OpenEmbedded OE that creates Linux distributions by producing root file systems packages and custom software 21 Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez I REPORT 1 INTRODUCTION and can build many of existing open source libraries and tools useful on and for embedded systems The heart of OE is Bitbake a tool that resolves dependencies between different software packages in order to build a complete embedded system For that purpose the tool needs a basic recipe consisting of a configuration file with information about the sources the dependencies as well as some options the compilation and the installation need The OE environment uses this informat
40. TO USB SERIAL CONVERTER PCB Datasheet Version 1 01 Future Technology Devices International Limited http www ftdichip com ttl232r pcbex htm Document Reference No FT_000065 SC1 2011 2011 SC1615740 750 760 Single UART with I2C bus SPI interface 64 bytes of transmit and receive FIFOs IrDA SIR built in support NXP Semiconductors Tau October 2010 October 2010 Tau 640 Slow Video Camera User s Manual Flir Commercial Systems Document Number TAU 0640 00 10 Version 100 A FACKELMEIER 2009 A FACKELMEIER E M BIEBL 2009 A Multistatic Radar Array for Detecting Wild Animals During Pasture Mowing Fachgebiet Hoechstfrequenztechnik Technische Universitaet Muenchen CERRA 2009 CERRA DANIELE ISRAEL MARTIN DATCU MIHAI 2009 PARAMETER FREE CLUSTERING APPLICATION TO FAWNS DETECTION German Aerospace Center DLR Remote Sensing Technology Institute IMF COLUMBIA UNIVERSITY COMPUTER CENTER 2011 COLUMBIA UNIVERSITY COMPUTER CENTER NOW CUIT 011 The Kermit Project http www kermitproject org ck90 html CORBET 1995 CORBET JONATHAN KROAH HARTMAN GREG RUBINI ALESSANDRO 1995 Linux Device Drivers O Reilly ELV 2010 ELV 2010 USB I2C Interface _Komplettbausatz inkl Gehaeuse bearbeitet und bedruckt USB Kabel 3 Anschlusskabel http www elv downloads de bilder artikel normalneu 84123_1 jpg GUMSTIX 2011a GUMSTIX 2011a Bitbake amp OpenEmbedded
41. Term terminal program read directly the output data Before running any test the Gumstix Overo System must be loaded Tests can be perform by connecting the USB connector of the EB with a computer and using a communication software The required configuration for the communication tool is explained in section 2 2 1 1 Once the system is loaded as shown in Fig 4 1 the driver must be inserted in the kernel using the command insmod With the command mknod the character device is linked to the driver and the application can be loaded It is necessary to repeat those steps for both devices 4 1 1 Tests with the help of an oscilloscope The first step is to check if the driver in kernel space works This is performed by measuring the voltage level in different pins of the hardware at the EB The EB was designed with extra slots that connected in parallel to the devices increase the number of possible connections Figures 4 2 and 4 3 show respectively the back and front general views of the Expansion Board with the available connections NEUGEBAUER 2011 Extra slots are useful for running tests and connect other devices The slots corresponding to the thermal camera are Linux driver development for components of the UAV based fawn detection system 53 Carmen Eva Ballesteros Gonz lez I REPORT 4 RESULTS Datei Bearbeiten Ansicht Suchen Terminal Hilfe The Angstrom Distribution overo ttyS2 Angstrom 2010 7 test 20101115 overo ttyS
42. XTAL2 1 5V 1 Veca Vec8 AO XTAL1 2 Al RESET 3 SCL 2 SCLA SCLB n c SC16IS740 RX 4 ELV USB I2C PCA9517 SCL TX 5 spa HM 3 SDAA SDAB SDA crs 6 IRQ RTS 7 8 GND EN 5 12C Vss Figure 2 4 Connection lines only related with the I C port of the circuit that connects the SC16IS740 chip with a PC 2 1 2 UART USB converter In order to connect the UART port of the SC1615740 chip to a computer either a UART USB converter or a UART RS232 is required For this project the USB to TTL serial UART converter TTL 232R PCB TTL 2010 developed by FTDI Chip was chosen The converter is a printed circuit board PCB which is USB powered and USB 2 0 full speed compatible It provides six outputs for the UART consisting of Tx Rx RTS CTS VCC and GND Information about the outputs can be found in Table 2 1 The resistor configuration in the PCB gives the chance of setting the UART signal whether at 3 3V levels or 5V levels TTL 2010 The more convenient choice is setting it at 3 3V which is the operating voltage of the SC16IS740 Figure 2 5 shows the circuit corresponding to the UART side By combining the circuit related to the I C port Fig 2 4 and this one Fig 2 5 the whole circuit to test the SC1618740 1s already complete Linux driver development for components of the UAV based fawn detection system 27 Carmen Eva Ballesteros Gonz lez I REPORT 2 DEVELOPMENT
43. achine as shown in Figure 1 3 The first prototype is a cantilever arm mounted on the mower that scans the following swath looking for wild animals from a height of 1 2 meters The signal is processed before the mower reaches the scanned swath In the experiment shown in Figure 1 4 infrared sensors microwave sensors distance sensors infrared cameras and cameras with visible spectral range are combined for this purpose Experience has shown that a camera based system is unfavorably because of the high speed of the mowing machine considering the low height it is assembled at and the vibrations caused by the terrain Infrared microwave and proximity sensors look more promising and therefore will be traced Figure 1 4 Testing model of extension arm Figure 1 3 Design of mower with extension incorporated in mower Source arm Source ISRAEL 2010b ISRAEL 2010a Microwave sensors can detect objects that contain a considerable amount of water The extension arm uses this kind of sensors to detect deer fawns in the swath of grassland The sensor has a certain angle of incidence as shown in Figure 1 5 to detect the reflected Linux driver development for components of the UAV based fawn detection system 15 Carmen Eva Ballesteros Gonz lez I REPORT 1 INTRODUCTION waves The slope angle has as advantage that the receptor won t receive the reflected microwaves from the ground or puddles but isolated objects as deer fawns can
44. ameters The function set_termios is called when an application tries to set the serial port parameters In the case of the generic driver for SC161S740 this function is crucial as 1t is the responsible of translating the received parameters into specific orders that change the registers of the chip For example when writing set speed 19200 in a terminal program it must write 0x06 in the register 0x00 The sending is performed using SMBus functions There are many ways to perform the translation using a preset table is one of them In tty_operation there are no conventional read functions instead the tty driver is responsible for sending any data received from the hardware to the tty core when it is received The tty core buffers the data until it is asked for by the user Because of the buffering logic the tty core provides it is not necessary for every tty driver to implement its own buffering logic The tty core notifies the tty driver when a user wants the driver to stop and start sending data but if the internal tty buffers are full no such notification occurs Characters that are received from the tty driver to be sent to the user are added to the flip buffer with a call to tty_insert_flip_char In order to push the data to the user a call to tty_flip_buffer_push is made The implementation of the i2c_driver is the same as the one seen in section 3 2 1 During its implementation it instantiates the i2c_client later used inside the termi
45. ance sensor Through the communication made possible by the driver the COM shall be able to optimize the parameters that define the captured image of the thermal camera in order to obtain an image that can be analyzed to detect the fawn deer verify the accuracy of the Google Maps Elevation API used by the autopilot of the UAV The COM shall be able to read the measures of the distance sensor so the actual distance to the ground can be known The software needed to fulfill this requirements shall be able to be executed in the computer on module The COM runs a Gumstix Overo System with a Linux Kernel Although it is possible to compile code directly in Gumstix for practical reasons the software was developed Linux driver development for components of the UAV based fawn detection system 59 Carmen Eva Ballesteros Gonz lez I REPORT 2 5 CONCLUSION AND OUTLOOK in a PC and later executed in the COM For this purpose a special software environment was required in order to build compatible executables with Gumstix In order to prosecute the tasks and accomplish the requirements the following software was developed A character driver inserted in the kernel This driver is responsible of e establishing the connection with the SC16IS740 through the I C bus e setting the configuration for the serial port and e defining the necessary functions to be accessed from an application in the user space An application personal
46. aplicaci n en user space Para cada dispositivo se desarroll una aplicaci n personalizada Ambas aplicaciones tienen la misma estructura Primero se crea un mensaje que pueda ser reconocido por el dispositivo Despu s se usan las funciones open write y read para respectivamente configurar el conversor enviar el mensaje y leer la respuesta La respuesta es analizada y en caso de detectarse alg n error vuelve a enviarse el mensaje al dispositivo hasta un m ximo de tres veces Tanto la respuesta definitiva como los errores en caso de haberlos son reportados al usuario Antes de cerrarse la aplicaci n ejecuta la funci n close del driver Linux driver development for components of the UAV based fawn detection system vu Carmen Eva Ballesteros Gonz lez RESUMEN USER SPACE KERNEL SPACE SMBus functions O OS Figura 1 3 Estructura del driver desarrollado La c mara admite un c digo hexadecimal con doble c digo de comprobaci n de errores Esta codificaci n es muy poco intuitiva para el usuario por ello en la aplicaci n se ha desarrollado un traductor que convierte mensajes del formato par metro valor a dicho c digo y genera autom ticamente el c digo de comprobaci n Igualmente analiza en la respuesta que no haya habido errores de transmisi n y que la c mara haya ejecutado sin problemas el mensaje El sensor de distancia es m s simple al admitir s lo caracteres que indican si debe rea
47. are the settings for the serial port The configuration of the serial port is performed by setting certain values in the registers of the SC16IS740 interface A list with the description of the internal registers and the bit settings can be found in the product data sheet of the chip SC1 2011 It might be necessary to highlight that the id of the internal registers in that list does not directly correspond with the register address In order to obtain the register address the table 1 1 must be applied where A 3 0 correspond to the register id Bit Name Function 7 not used 6 3 A 3 0 UART s internal register select 2 1 CH1 CHO channel select CH1 0 CHO 0 Other values are reserved and should not be used 0 not used Table 1 1 Register address byte for the internal registers in SC16IS740 SC1 2011 In section 3 1 3 it is explained the obtaining of the necessary commands for configuring the serial port for the thermal camera TAU640 as well as for the sensor MLR100 Before going directly to the code a brief explanation about how the driver was programmed can help to understand better what follows The developed driver has two essential parts Ani2c_ driver with an attached 12c_client that helps with the communications through the PC bus A character driver with an implemented struct file_operations that enables the communi cation with the user The configuration is performed in the functi
48. arrera Pulse Width Modulation Red green and blue Request To Send Receive Serial Clock Serial Data System Management Bus Serial Peripheral Interface Transistor transistor Logic Teletypewritter Transmit Universal Asynchronous Receiver Transmitter Universal Serial Bus Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez 10 PART I REPORT Chapter 1 Introduction 1 1 Problem situation and motivation Every year circa 100 000 roe deer fawns are killed by the harvesting machines during mowing actions in Germany JARNEMO 2002 A total of around 500 000 wild animals die every year in these conditions CERRA 2009 It happens mostly between May and June coinciding the end of the growing seasons with the period when the baby deer are born The mother leaves the new born fawns in the high grass hidden from their natural predator while looking for food During the first three to eight weeks of life roe deer fawns face danger situations by remaining instinctively motionless on the ground The lack of motion their natural camouflage and their small size make their detection more difficult Other animals like rabbits and brooding birds are also victims of the harvesting machines Even for adult wild animals it is difficult to escape from the commonly operating width of 6 14 meters and the operating speed of 12 20 km h KURT 1968 For the agriculturist it is impossib
49. ase struct inode xinode struct file filep module_put THIS_MODULE return SUCCESS The read function reads from the FIFO of the SC1615740 using the SMBus function i2c_smbus_read_i2c_block_data and uses copy_to_user to copy the data into the user space static ssize_t my_read struct file xfilep char buffer size_t length loff_t xoffp s32 ret 0 int i 0 j 0 u8 values BUF_LEN struct scl6is740 my_sc struct scl6is740 filep gt private_data if i2c_check_functionality my_sc gt client gt adapter I2C_FUNC_SMBUS_READ_BYTE_DATA if length gt BUF_LEN length BUF_LEN ret i2c_smbus_read_i2c_block_data my_sc gt client reg_RHR length value copy_to_user buffer void values ret return ret a The write function gets the data from the user space using copy_from_user and sends it through the i c port using i2c_master_send static ssize_t my_write struct file filep const char buffer size_t length loff_t xoffp ssize_t data_left 1 unsigned char data length 1 struct scl6is740 my_sc struct scl6is740 x filep gt private_data if i2c_check_functionality my_sc gt client gt adapter I2C_FUNC_SMBUS_WRITE_BYTE_DATA data_left copy_from_user data 1 buffer length data 0 reg_RHR 12c_master_send my_sc gt client data length 1 Linux driver development for components of the UAV ba
50. ation should be compiled with the cross compiler in order to make sure the execute file is compatible with the Gumstix System In case of using the OE cross compiler the Makefile must include OVEROTOP home USER overo oe CROSS_COMPILE OVEROTOP tmp sysroots i686 linux usr armv7a bin arm angstrom linux gnueabi Once the application is ready to be compiled it can be performed by executing make in the directory where the application is located This directory should be inside the user collection main directory of the cross compiler More information about the cross compiler can be found in section 2 2 4 and GUMSTIX 2011a The best way to show how to create an application is with an example The following code represents a simple application that just opens and closes the device include lt stdio h gt include lt stdlib h gt include lt string h gt include lt unistd h gt include lt sys types h gt include lt sys stat h gt include lt fcntl h gt int main int argc char argv int file open dev device O_RDWR close file return 0 But only opening and closing the device is useless As it was already explained in section 3 2 1 thanks to the char_driver inside the device driver it behaves like a file The user can open close write and read the device as if it were a file The function ioctl can be also implemented in the driver It is used to attend order
51. atus Byte is mostly important in the response messages as it indicates the receipt of the previous incoming message Its possible values are shown in Table 3 5 The Function Code FC is a byte indicating which command will be executed Tau 640 Slow Video Camera User s Manual Tau October 2010 contains all available functions the camera is able to interpret i e the corresponding Function Byte Byte Count and the data range that the packet is allowed to carry The Byte Count BC indicates the amount of data bytes sent in the packet It takes up a total of two bytes and it must be an even number between 0 and Ox1F4 In case its value is 0 the command will end after the first CRC code The cyclic redundancy check CRC is an error detecting code that encodes any incoming block data with the help of a check value with a fixed length using systematic cycle codes The result has also a fixed length It is commonly used to detect data corruption caused by noise in transmission channels The algorithm can be easily implemented as well in hardware as in software The one used in the camera and therefore in the program too is the called Linux driver development for components of the UAV based fawn detection system 48 Carmen Eva Ballesteros Gonz lez I REPORT 3 DEVELOPMENT OF THE LINUX DRIVER CRC 16 CCITT which uses as check value the polynomial x x 2 1 represented in hexadecimal as 0x1021 CRC1 is calculated from the first 6 b
52. building the kernel module OVEROTOP home USER overo oe CROSS_COMPILE OVEROTOP tmp sysroots i686 linux usr armv7a bin arm angstrom linux gnueabi KERNEL_PATH S OVEROTOP tmp sysroots overo angstrom linux gnueabi kernel ARCH arm Neither KERNEL_PATH nor ARCH are required for building user modules As it will be clarified in next chapter the required driver will actually have two parts First there is a user application The user will interact only with this application In Linux a user application is not allowed to manage directly the system s hardware but through the kernel supported functions For that purpose another software must also be developed and inserted inside the kernel in order to interact between the app and the hardware Linux driver development for components of the UAV based fawn detection system 33 Carmen Eva Ballesteros Gonz lez I REPORT amp 2 DEVELOPMENT OF THE TEST ENVIRONMENT Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez 34 Chapter 3 Development of the Linux driver Aim of the master s thesis is to program drivers for controlling the thermal camera and the laser distance sensor integrated in the octocopter Both devices can only communicate through serial ports but there are no more available UART connections at the COM so it becomes necessary to find another way to connect both device
53. cation can obviously change depending on the devices connected to the computer After executing it if the Overo Board is correctly connected to the computer and once the power adapter is plugged Gumstix will automatically boot 2 2 1 2 HTerm HTerm HAMMER 2008 is a GUI terminal program for real and virtual serial interfaces that works under Windows and Linux As shown in Fig 2 6 the connection is configurable and it helps to execute the test in a handy way Beside the choice of the port the other important given settings are Baudrates from 300 to 256000 Bd Data 5 6 7 or 8 bits per word a Stop bit 1 1 5 or 2 Parity none even odd mark space Gives the option of CTS flow control The program was used to test the correct configuration of the SC161S740 chip 3 1 3 UART configuration for the SC16IS740 as well as to try different inputs checking out the correctness of the output data During the driver tests several trials connecting the EB to the PC instead of to the corresponding device were done because it eases the debugging process see section 4 1 2 2 2 2 TAU640 thermal camera connected to the computer Before programming the application that helps to change the configuration of the camera it is recommended to test first how the camera works This is performed by connecting the thermal camera to a computer To connect the camera to the PC a UART USB converter as the one explained in section 2 1 2 was needed
54. client to hold the information of the i c device The kernel already provides some tools collected in the i2c_core to use the i c port and by adding an i2c_driver with probe and detach functions to bind and unbind the device the communication through the i c port will be easily attained Therefore it is necessary to attach the file_operations to the character device and to register an i2c_driver in the 12c_core The diagram in figure 3 6 shows how the driver remains Lastly the function _exit unregisters the device and frees the memory Linux driver development for components of the UAV based fawn detection system 43 Carmen Eva Ballesteros Gonz lez I REPORT 2 3 DEVELOPMENT OF THE LINUX DRIVER A USER APPLICATION user space CHAR_DRIVER software kernel C CLIENT t 2 C MASTER 12C BUS SC1615740 Figure 3 5 Global diagram of the interaction of the different layers in the developed software both in kernel and user space hardware file_operations CHAR_DRIVER 12C DRIVER f 2c cient Figure 3 6 Diagram of the driver in kernel space static struct i2c_driver my_driver driver name DEVICE_NAME owner THIS_MODULE r id_table scl6is740_id probe scl6is740_probe attach_adapter scl6is740_attach Linux driver development for components of the UAV based fawn detection system 44 Carmen Eva Ballesteros Gonz lez I REPORT 3 DEVELOPMENT OF THE L
55. command is ready to be sent it opens the device by file open dev tau640 O_RDWR As all the functions of the camera are already defined it is also known the length of the expected answer Knowing that the FIFO is reset to a variable value each time the device is opened in order to verify that an answer is received first of all the FIFO will be read Afterward the command is sent and some microseconds later the FIFO is read again The first read is compared to the second one In case both are different the actual answer will be checked by confirming that the status of the camera is the expected 0x00 and checking both CRC codes In case any of those verifications fails the message will be sent a maximum of three times until there is a positive answer Finally the device will be closed read file ini_answer my_data ANS length if write file my_datalsc command my_datal lsc length SUCCESS read file my_data ANS command my_data ANS length close file 3 2 3 User Application for the laser distance sensor MLR100 The MLR100 laser distance sensor makes all its communications through the UART port and only accepts a few specific commands consisting of an only character Range g Gets a new range if not sleeping a Sleep s Goes to lower power mode Wake up w Goes to normal power mode Linux driver development for components of the UAV based fawn detection system 49 Carme
56. ed lies as appendixes Appendix 1 explains how to configure the serial port settings in driver for the SC16IS740 Appendix 2 explains how to develop an application for both drivers Appendix 3 contains the commands for the application developed for the TAU640 camera Appendix Linux driver development for components of the UAV based fawn detection system 22 Carmen Eva Ballesteros Gonz lez I REPORT e 1 INTRODUCTION Level Shifter Digita Video Console Port I IC master Computer On Module USB Host EEPROM Level Supply Shifter A Backup y Tranceiver Battery 5y LED Taster Y Y Falcon 8 Connector Figure 1 12 Connection between the COM and both the thermal camera and the laser distance sensor 4 contains the allowed arguments for the application developed for the laser distance sensor MLRI00 Linux driver development for components of the UAV based fawn detection system 23 Carmen Eva Ballesteros Gonz lez I REPORT 1 INTRODUCTION Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez 24 Chapter 2 Development of the test environment Before starting developing the software some preliminary tasks were required This chapter contains the previous preparation that includes the required software environ
57. egistered with the kernel In order to register the terminal driver with the kernel it is necessary to perform two steps VENKATESWARAN 2008 Linux driver development for components of the UAV based fawn detection system 50 Carmen Eva Ballesteros Gonz lez I REPORT amp 3 DEVELOPMENT OF THE LINUX DRIVER tty_operations TTY_DRIVER LINE DISCIPLINE kernel space software hardware Y UART oi Figure 3 7 Global diagram of the different tools interacting in the generic driver for SC16IS740 1 Call tty_register_driver struct tty_driver tty_d to register itself with the tty core 2 Register the device with tty_register_device struct tty_driver tty_d unsigned de vice_index struct device device Attached to the tty_driver stays the struct tty_operations with all the functions associated to the driver CORBET 1995 From all of them the most important are open close write write_room and set_termios Anyway even if not defined all functions from tty_operations must be declared open The open function is called when the port is opened The tty core calls the function with a pointer to the tty_struct assigned to this device and a file pointer When this open function is called the tty driver is expected to either save some data within the tty_struct variable or save the data within a static array that can be referenced based on the minor number of the port This is necessary so the tty driver k
58. em a 56 4 6 From left to right captured image with contrast 20 50 and 70 58 5 1 Connection between the COM and the devices through the SC16IS740 interface 59 5 2 Diagram of the layers in the developed software 2 2 2 Cum 60 Linux driver development for components of the UAV based fawn detection system 6 Carmen Eva Ballesteros Gonz lez List of Tables 1 1 Port settings of the RS 232 serial interface of the camera TAU 640 20 2 1 TTL 232R PCB Input Output Descriptions 2 2 22m rennen 28 2 2 Pin Definition for the connection between MLR100 anda PC 32 3 1 SC16IS740 address map SC1 2011 o 39 3 2 SC1615740 register address byte SC1 2011 39 3 3 Baud rates of the SC16IS740 using a 1 8432 MHz crystal SC1 2011 41 3 4 This table set the register address of the different registers used in this section according to table 3 2 and the register id none 41 33 AS Byte nd rod o o a a wake Sl 48 1 1 Register address byte for the internal registers in SC16IS740 SC1 2011 67 3 1 Table with the available function commands in the application for the TAU640 camera 72 4 1 Arguments admitted by the application for the laser distance sensor MER100 73 Linux driver development for components of the UAV based fawn detection system 7 Carmen Eva Ballesteros Gonz lez DOCUMENT I REPORT 2 INDEX OF TABLES Linux driv
59. enter n 163 L Value 1 63 16 o 16383 Automatic Parameters Be 80 80 Plateau 150 10 100 Brightness Bias l Video On off Video Standard Oon Oot Onse Opa IT Mean 127 0 255 Ensure an FFC is performed after making a change to the Video Standard Press the Save Settings button on the Setup pane for Max Gain 8 0 255 power on defaults totake effect T Fine Video Color O Color O Monochrome 3 7 FPA WB Connected MSCOMM Ready Part 42640001X en Connected MSCOMM Ready Part 42640001 Size 640x512 Figure 2 7 Setup Tab and AGC Tab of the FLIR Camera Controller GUI Source Tau October 2010 Figure 2 8 Interface Adapter Board of the MLR100 sensor with the pins from the UART numbered There is already a GUI software developed by Aerius Photonics Aerius MLR PC Control Software Aer 2009 that allows PC control of the laser distance sensor MLR100 However HTerm was used for testing the format of the inputs and outputs that the device allows The required configuration for the COM port is a Baud rate 19200 Data bits 8 Parity None Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonzalez 31 I REPORT 2 DEVELOPMENT OF THE TEST ENVIRONMENT Pin Number Definition 1 Tx 2 Rx 3 Ground 4 Power gt 4V lt 40V Table 2 2 Pin Definition for the connection between MLR10
60. er development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez List A D ACK API BC CCITT CH CMOS COM CR CRC CTS DLH DLL EB EN PC ICAI IR IrDA FC FCR FFC FIFO GND GPIO GPS GUI LCR LDISC LDS LF LSB LVDS MMC MSB NA OE OS OTG PC of Abbreviations Analog Digital Acknowledge Application programming interface Byte Count International Telegraph and Telephone Consultative Committee Channel Complementary Metal Oxide Semiconductor Computer on module Carriage Return Cyclic Redundancy Check Clear To Send Divisor Latch MSB Divisor Latch LSB Expansion board Enable Inter Integrated Circuit Insitituto Cat lico de Artes e Industrias Infrared Infrared Data Association Function Code FIFO Control Register Flat Flex Cable First In First Out Ground General Purpose Input Output Global Position System Graphic User Interface Line Control Register Line Discipline Laser distance sensor Line Feed Less Significant Bit Low voltage differential signaling Multimedia Card Most Significant Bit Negative Acknowledge OpenEmbedded Operating System On The Go Personal Computer Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez PCB PFC PWM RGB RTS RX SCL SDA SMBus SPI TTL TTY TX UART USB DOCUMENT I REPORT 2 LIST OF ABBREVIATIONS Printed circuit board Proyecto Fin de C
61. figured for the specific attached device Instead of the generic driver a particular software for each device both the camera and the sensor was developed The software includes a character driver with the specific configuration for the serial port already set and a personalized application for the corresponding attached device Figure 3 2 may clarify the difference between the driver actually developed and conceived generic serial driver Generic driver SC161S740 PC 12 Bus 2C Tx Master Slave Rx y Driver for the specific device Comm O Pro User Kernel space Dspace GUMSTIX Figure 3 2 The aim of the generic driver is that the user can communicate through it as it were a serial port The user would interact with the attached device using a communication tool see section 2 2 1 that needs to be configured for the certain device attached to the chip The developed driver is specified for the attached device and manages it in an optimal way The user interacts directly with the device through the application Hereafter follows a detailed description of the chip its necessary configuration and the development of the driver as well in kernel space as in user space and the steps to develop the generic terminal driver for the SC1615740 3 1 SC161S740 Chip The SC16IS740 is an interface that enables a bidirectional protocol conversion from UART to I C SPI The cho
62. g methods of resolution were so far prosecuted Linux driver development for components of the UAV based fawn detection system 13 Carmen Eva Ballesteros Gonz lez I REPORT 1 INTRODUCTION Mechanical rescue system mounted at the mowing machine Years ago a mechanical device with the form of tines was attached in the front of the mower preventing the machine taking the wild animals by lifting them instead and therefore saving them This method is no longer effective nor found in today s agriculture technology Instead nowadays it is used a horizontal arm with pipes or chains vertically attached that sweeps the following lane flushing out the wild animals Combing with dogs Another option is scanning the field before mowing Dogs are really useful in this case because of their sense of smell and they can be trained to perceive the smell of the deer fawns and then scare them This method has however a disadvantage It takes a lot of time to trail a whole field even with multiple searchers The aggravating factor of the geometrical conditions showed in Figure 1 1 should be also taken into account At an average vegetation height of one meter a 0 3 meter long deer fawn can be found by a 1 7 meter tall searcher if it is inside a radius of 0 5 meters The higher the grass is the more difficult it is to find the fawn If there is grass over the fawn even just being half a meter away might not be enough Figure 1 1 Geome
63. guration and remote control is provided via a RS 232 serial interface consisting of signals named RX TX and GND using 3 3 volt signal levels Outgoing messages are only generated as a response of each incoming command The serial port settings are shown in Table 1 1 The real time digital video is provided by a digital parallel channel The XP Bus may be configured through software for three different digital data channels The BT 656 channel transmits pixels in a video data signal format called YUV that contains image symbol and color information The CMOS channel is a parallel image data output The raw data are directly sent not requiring transference or conversion via a video capture card The serial low voltage differential signaling LVDS This channel consists of three signal lines a clock a composite sync frame sync and data valid and serial data The camera is connected to the computer on module through two communication lines The RS 232 serial interface used for the configuration is connected through a UART I C converter SC1618740 to one of the I C connectors of the COM The digital video data travels through the 27 pin Flat Flex Cable FFC connection The chosen digital data channel will be the BT 656 3http www gumstix com http www flir com cvs cores view id 51374 Linux driver development for components of the UAV based fawn detection system 19 Carmen Eva Ballesteros Gonz lez I REPORT 1 I
64. hat converts from UART to C connects the serial port of each sensor with the computer on module via I C bus The driver must manage the added interface and act like a bridge between the user and the sensors An application for each sensor is also developed in order to facilitate the user to control both devices Linux driver development for components of the UAV based fawn detection system XVII Carmen Eva Ballesteros Gonz lez A mis padres por ayudarme a cumplir mis objetivos como persona y estudiante por brindarme los recursos necesarios confiar en mis decisiones y haberme aconsejado siempre que lo he necesitado A mis abuelos Engraciano y Carmen a los que admiro por todo el cari o y nimo recibidos haber creido siempre en mi y por servirme como motivaci n e impulso para hacer realidad mis sue os Y finalmente a mi hermano por saber comprenderme haberme servido de apoyo cuando lo he necesitado y tener la habilidad de sacarme una sonrisa incluso en los momentos m s dif ciles Acknowledgements Foremost I am heartily thankful to my supervisor at DLR Dipl Ing Martin Israel for his patience motivation enthusiasm and expertise He has made available his support in anumber of ways and provided me guidance and assistance from the initial to the final level of this project I would like to thank my supervisor at Technische Universit t Darmstadt Dipl Ing Kerstin Gross for her patience and friendly help I am g
65. http gumstix org software development open embedded html Linux driver development for components of the UAV based fawn detection system 63 Carmen Eva Ballesteros Gonz lez I REPORT 2 REFERENCES GUMSTIX 2011b GUMSTIX 201 1b OpenEmbedded Directory Layout http gumstix org software development open embedded 161 openembedded directory layout html HAMMER 2008 HAMMER TOBIAS 2008 HTerm http www der hammer info terminal HARDER 2008 HARDER STEFAN 2008 Messkampagne des Forschungsprojektes Wildretter HOLZHAUER 2009 HOLZHAUER M ROEST HI DE JONG MG Vos JH 2009 Botulism in dairy cattle in 2008 symptoms diagnosis pathogenesis therapy and prevention Tijdschr Diergeneeskd PubMed PMID 19645252 ISRAEL 2010a ISRAEL M SCHLAGENHAUF G FACKELMEIER A HASCHBERGER P 2010a Untersuchungen zur Wilderkennung beim Maehen ISRAEL 2011a ISRAEL MARTIN SCHLAGENHAUF GUENTER HUNKE MAIK HASCHBERGER PETER BIEBL ERWIN FACKELMEIER ANDREAS HEDTRICH PHILIPP RUPPRECHT VERONIKA 2011a Abschlussseminar Projekt Wildretter ISRAEL 2010b ISRAEL MARTIN 2010b Mit Infrarottechnik Wildtiere vor dem Maehtod retten ISRAEL 2011b ISRAEL MARTIN 2011b A UAV BASED ROE DEER FAWN DETECTION SYSTEM In Conference on Unmanned Aerial Vehicle in Geomatics JARNEMO 2002 JARNEMO A 2002 Wildlife Biology vol 8 Roe deer Capreolus capreolus fawns and mowing
66. ice between the I2C bus or the SPI interface depends of the voltage of the pin 8 Fig 3 3 SC1 2011 If the pin is at logic high the I C bus interface is selected Logic low means the SPI interface is selected The chip is provided with a FIFO buffer that can store up to 64 characters including three additional bits of error status per character for the receiver FIFO from both the transmitter and receiver To use it and relieving the host of excessive software overhead by buffering received transmitted characters the SC161S740 needs to be placed in the FIFO mode The way to enable the FIFO is explained in 3 1 3 The Expansion Board has two SC16IS740 integrated one connected to the thermal camera and the other one to the laser distance sensor Both are connected to the COM through the Linux driver development for components of the UAV based fawn detection system 36 Carmen Eva Ballesteros Gonz lez I REPORT 3 DEVELOPMENT OF THE LINUX DRIVER Voo 1 O 1 XTAL2 AO 2 2 XTAL1 Al 3 3 RESET n c 4 SC161S740IPW 4 RX SCL 5 SC16IS740IPW Q900 5 TX SDA 6 6 CTS IRQ 7 7 RTS 12C 8 8 Vss Figure 3 3 Pin configuration for TSSOP16 with I C bus interface I C bus and to the corresponding device through the UART The simple diagram circuit shown in Fig 3 4 helps to visualize this connection 12C Bus SDA SCL
67. ideo LUT to sepia can be performed by writing root overo configtau640 lut sepia Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez 72 Chapter 4 Application for the laser distance sensor MLR100 The aim of this application is to establish the communication between the user and the laser distance sensor Table 4 1 collects all the commands the sensor admits The most important ones for the project are Range Gets the distance measured by the sensor This is useful to verify the accuracy of the Google Maps Elevation API and get the real distance to the ground Sleep The sensor goes to lower power mode This is useful to save battery and increase the flight autonomy The application only admits one argument If there are more all of them but the first one will be ignored Command Name Description g Range Gets a new range if not sleeping s Sleep Goes to lower power mode w Wake up Goes to normal power mode r Ready Shows that communications are ready but it needs to be awake to take a new range m Menu Displays this menu on the terminal Also help can be used for this purpose Table 4 1 Arguments admitted by the application for the laser distance sensor MLR 100 An example of how to execute the application root overo mlr100 g Linux driver development for components of the UAV based fawn detection
68. ion in order to assemble the package to the complete build system A more detailed explanation about how the cross compiler works and how it was used for the development of the drivers can be found in section 2 2 4 Cross Compiler 1 4 Assignment situation and task structuring The task of this master thesis consists in developing the necessary drivers that enables the communication between the COM and the thermal camera and between the COM and the laser distance sensor The need of this communication stems from two different reasons On the one hand the height of the sun certain weather conditions and the terrain characteristics have influence on the parameters of the thermal camera such as to optimize the detection of deer fawns Therefore the parameters need to be often readjusted On the other hand as explained before in Fig 1 7 it is important to know the scale of an image when processing it In sloping terrains the height at which the image is taken can vary affecting the scale The connection of both components to the COM is not direct Both devices can only communicate through serial ports but there are no more available UART connections at the COM so it becomes necessary to find another way to connect both devices to other ports of the COM With the help of a UART to I2C converter the components can be connected to the still available I C ports of the COM The responsible chip for the conversion is the SC1618740 interface SC1 2011
69. is executed The thermal camera admits a very particular hexadecimal code with double cyclic redundancy check code This encoding is not quite user friendly therefore the application was developed with a translator from messages with the format parameter value to the aforementioned code and also generates automatically the check code It analyzes as well the answer from the device looking for transmission errors or problems in the status of the camera The laser distance sensor is much simpler as it only admits characters indicating if the sensor must take a new measurement or change between the normal power mode and the lower power mode The sensor can only take measures while the normal power mode is activated Because of that the developed application set the sensor in normal power mode before asking for the measure After receiving the answer from the sensor the device is set in lower power mode in order to reduce the consumed power to minimal 1 3 Results In order to test the developed software it is necessary to insert first both drivers with the kernel using insmod tau640 ko for the camera and insmod mlr100 ko for the sensor The application of the camera is executed using the structure configtau640 parameter value A list with all the parameters and values range admitted by the application for the thermal camera is allocated in Appendix C on the report of the thesis The application was tested connecting a monitor to the video
70. is to make it possible to change certain parameters in order to obtain a useful image The EB is supplied with extra slots for the analog video output of the thermal camera By connecting a monitor to this slot it is possible to visualize the changes in the image when sending certain commands to the camera The analog video output is a two wire connection The data is encoded in a YUV format that provides the information in terms of the luma brightness and chrominance color In order to visualize the image a monitor that supports this format is required Once the camera is connected the monitor is plugged in and the driver is inserted in the kernel the application can be tested As seen in Appendix 3 there are many commands that the application acknowledge so only the crucial ones will be shown as examples in this section Appendix 3 contains the functions that the application for the thermal camera TAU640 admits Besides there is one more possible kind of argument that the application admits It consists in introducing manually the code leaving the places where the check value CRC should be calculated as space characters The application itself calculates the CRC and sends the whole command to the device The correct generation of the code was already checked while testing the application with the EB connected to the PC It is necessary now to prove if the camera actually accepts the commands and if the application can read the real answer f
71. itivo a trav s del bus I C Esto puede realizarse usando un i2c driver del i2c core perteneciente al kernel de Linux 3 El driver desarrollado se inserta en el kernel mediante insmod Esto ejecuta una funci n del driver llamada module_init En dicha funci n se procede al registro del character driver en el kernel y del 12c driver en el 12c core El driver puede ser as mismo retirado del kernel mediante rmmod que ejecuta la funci n module_exit Cuando el i2c driver es registrado en el i2c core ste ejecuta unas determinadas funciones llamadas probe attach_device y detect_client El driver desarrollado se encarga de recopilar la informaci n concerniente al bus y la direcci n del conversor durante la ejecuci n de dichas funciones y la almacena en una estructura llamada i2c_client El character driver posee una estructura llamada file_ operations con funciones como open close write y read que pueden ser usadas por aplicaciones Dichas funciones deben definirse en el kernel space El driver es desarrollado de manera que en open se configura la interfaz UART C de acuerdo a la configuraci n del puerto serie del dispositivo al que est conectado Tanto open como write y read usan la estructura i2c_client y las funciones provistas por el i2c core para poder comunicarse a trav s del bus IPC La Figura 1 3 muestra c mo interact an las estructuras m s relevantes dentro del driver 1 2 2 Desarrollo de la
72. ivamente ante el peligro tumb ndose y encondi ndose entre la hierba Su falta de movimiento su camuflaje natural y su peque o tama o dificultan su detecci n siendo imposible para el agricultor verlos desde la m quina cosechadora Desde la agencia aeroespacial alemana DLR se est n desarrollando diversos m todos para detectar los cervatillos en el campo antes de que pase la m quina cosechadora Uno de estos m todos consiste en usar un octoc ptero que sobrevuele el campo buscando dichos animales como muestra la Figura 1 1 Figura 1 1 Octoc ptero volando El octoc ptero lleva a bordo entre otros sensores dos c maras una en rango visible y otra en infrarrojo conectadas a ordenadores que analizan las im genes obtenidas Una vez se ha detectado el animal se env a la posici n exacta a otro ordenador que se encuentra en tierra Desde Linux driver development for components of the UAV based fawn detection system Vv Carmen Eva Ballesteros Gonzalez RESUMEN la centralita en tierra se pueden observar tambi n en tiempo real las im genes de las c maras Esto es til no s lo para corroborar la detecci n de animales sino tambi n para comprobar que la imagen obtenida por la c mara t rmica es v lida pues es sensible a las condiciones climatol gicas y puede ser necesario tener que reajustar la configuraci n durante el vuelo 1 1 2 Tarea asignada El objetivo principal del proyecto es desarrollar el software necesari
73. ized for each device that lets the user communicate automatically with the device Figure 5 2 shows the layers of the developed software USER APPLICATION Sea DRIVER KERNEL HARDWARE Figure 5 2 Diagram of the layers in the developed software As seen in Chapter 4 both developed software perform the required tasks Therefore the requirements of this project were fulfilled 5 2 Possible future improvements The drivers were specifically developed for the thermal camera TAU640 and the laser distance sensor MLR100 On the one hand personalizing the software has as advantage that it is optimal developed for the use of this specific hardware On the other hand it can be a problem if in a future the device is removed and substituted by another one with different characteristics There are three possible solutions to solve this problem Linux driver development for components of the UAV based fawn detection system 60 Carmen Eva Ballesteros Gonz lez I REPORT 2 5 CONCLUSION AND OUTLOOK While developing the required applications a generic application that sends any message without codification and reads the whole buffer of the SC16IS740 was developed One possibility is to use this application The driver inserted in kernel space can remain but it might need to be modified in order to adjust the serial configuration to the specific port settings of the new device Appendix 1 explains how to pe
74. le to detect the fawns from the harvesting machine and this situation leads to a distressful death of the animals MUERI 1999 ISRAEL 2010a During the silage the carcasses of those animals is mixed with the crop and later it is given as fodder for the dairy cattle Temperatures over 25 C within a protein full hermetically sealed environment conforms an ideal culture medium for the Clostridium botulinum bacterium This bacterium produces the Botulinum toxin which is considered the most powerful neurotoxin ever discovered An amount between 0 1 and 1 micrograms of this protein is enough to kill an adult person Getting the carcass into the harvest keeping it inside a silo and getting warm because of the fermentation fulfills the requirements that create the poison HOLZHAUER 2009 Once the dairy cattle consume the contaminated fodder they get a paralytic illness called Botulism This kind of intoxication is usually deadly and not directly treatable In a dairy farm this could mean the death of the animal or in extreme cases the death of the whole herd The economical losses are huge for the farm From an economical and also moral point of view it is necessary to develop a system capable of detecting the roe deer fawns in time 1 2 Previous methods of resolution Several methods to avoid the killing of those animals during the harvest were proven in order to let the agriculturist mow their field risk less The followin
75. lizar una medida o si debe cambiar entre modo normal y modo de baja energ a La aplicaci n desarrollada se encarga de despertar al sensor antes de cada medici n y volver a dejarlo en modo de baja energ a antes de cerrar la aplicaci n De este modo se intenta consumir el m nimo posible de bater a para que la autonom a de vuelo se vea m nimamente afectada 1 3 Resultados Para poder comprobar el funcionamiento del software primero debe insertarse el driver en el kernel mediante insmod tau640 ko para la c mara e insmod mlr100 ko para el sensor La aplicaci n de la camara se ejecuta con comandos que siguen la estructura configtau640 parametro valor La lista con los parametros y rango de valores admitidos por la aplicaci n se encuentra en el anexo C de la memoria La aplicaci n fue probada conectando un monitor a la salida de video de la c mara y comprobando que efectivamente la imagen cambiaba de acuerdo a los comandos introducidos Como ejemplo en la Figura 1 4 se muestran diversas capturas tras probar los valores para el contraste 20 50 y 70 y debajo de estas l neas se encuentra un ejemplo del funcionamiento de la aplicaci n root overo configtau640 contrast 100 Sent 6e 0 014 0 2605a 0642c22 Answer 6e 0 014 0 2605a 0642c22 Linux driver development for components of the UAV based fawn detection system VII Carmen Eva Ballesteros Gonz lez RESUMEN Figura 1 4 De izquierda a derecha im genes capturadas
76. lso an autopilot software developed by AscTec that in combination with the waypoint planning software developed by DLR allows the UAV to fly over a given area scanning efficiently the terrain 1 3 2 Hardware components 1 Computer on module Linux driver development for components of the UAV based fawn detection system 18 Carmen Eva Ballesteros Gonz lez I REPORT 8 1 INTRODUCTION The core of the measure system is a small Computer on module COM developed by Gumstix Its specifications are detailed in Figure 1 9 Processor OMAP35xx with Cortex A8 CPU velocity 600 MHz or 720 MHz Memory 512 MB or 256 MB Low Power DDR RAM 256 MB NAND Flash On the board Micro SD Slot Dimensions 58 mm x 17 mm x 4 4 mm a Weight 6 g Figure 1 9 Gumstix Overo COM Source www gumstix com The COM counts with one 27 pin Flat Flex Cable FFC connection which is located on the upper side of the module and provides a digital video interface for connection of cameras two u fl antenna connectors and two 70 pin AVX 5602 Board To Board Connectors that makes a total of 140 signals for GPIOs I C 6 PWM lines 6 A D 1 wire UART SPI Extra MMC lines Headset Microphone Backup battery High Speed USB Host and USB OTG 2 Thermal camera The thermal camera is the model TAU 640 from the company FLIR Commercial Systems 4 This camera covers almost the whole long wavelength infrared region detecting wavelengths from 8 to 14 um Confi
77. ment and both hardware and software tools to test the device The first task is to test the SC1615740 interface by connecting it to a PC For that purpose it was necessary to add some hardware devices as converters and level shifters and to use a terminal program to establish the communication The idea is to test first the outputs of some specific entries and then to connect the devices for which the driver will be programmed in order to find the correct way to send the commands and to check the reaction of the device as well as the response Once the chip is tested the second task is to program and some software tools where used for achieving that purpose Although it is possible to compile code directly in Gumstix for large projects it is more comfortable to use cross compilation or the OpenEmbedded Cross build system This way it can be developed from a PC and then tested in the Overo System The tests were carried out thanks to a communication software tool All the previous preparations to the development of the software are explained in detail below 2 1 Hardware tools The SC16IS740 is an interface that enables a bidirectional protocol conversion from UART to C The operating voltage can be either 3 3 V or 2 5 V It also provides internal registers a 64 bytes FIFO buffer and supports a fully bidirectional RS 485 Further technical specifications of the device are explained in section 3 1 The easiest way to test the behavior is
78. n 2 2 1 2 emulates the device and therefore the sent messages are visualized and the answers are controlled in order to test all possible scenarios Linux driver development for components of the UAV based fawn detection system 54 Carmen Eva Ballesteros Gonz lez I REPORT 4 RESULTS Board To Board Connector EEPROM Console Port UART Interface Gumstix J4 IR Camera e Video Connector Digital Video Gumstix Level Shifter eee lit ll wl USB Host Backup Battery Voltage supply LEDs RS232 Interface Pushbuttons LDS Connector plug Board To Board Connector Gumstix J1 Figure 4 2 General view of the back side of the Expansion Board Source NEUGEBAUER 2011 Analog Video Output UART Conductor Video Connector Thermal Camera Video Connector Thermal Camera RGB Camera Thermal Camera Soldered connection Soldered connection LDS Soldered connection USB OTG USB HOST Figure 4 3 General view of the front side of the Expansion Board Source NEUGEBAUER 2011 Before performing the tests two preliminary tasks are necessary 1 First it is necessary to connect the extra UART slot to the PC using a UART USB converter as the one seen in section 2 1 2 2 Then the terminal program must be configured with the same parameters of the serial port of the device that the program is trying to emulate Figure 4 5 shows an example of the data received by HTerm when the application sends certain message
79. n Eva Ballesteros Gonz lez I REPORT amp 3 DEVELOPMENT OF THE LINUX DRIVER Ready r Shows that communications are ready but it needs to be awake to take a new range Menu m Displays this menu on the terminal Also help can be used for this purpose As seen above the sensor can only take measures while the normal power mode is activated Because of that the developed application set the sensor in normal power mode before asking for the measure After receiving the answer from the sensor the device is set in lower power mode in order to reduce the consumed power to minimal As happened with the driver for the camera it interacts with the kernel space through the functions open read write and close First it takes the command verifying if it is one of the list above In case of identifying the command as g a flag will indicate that the device needs to be awaken and put to sleep respectively before and after the main command is sent To begin the communication with the device it must be opened file open dev mlr100 O_RDWR then the FIFO is read the character or characters are sent and before closing the answer is checked to confirm that is valid In case the answer is not valid it sends the problematic command again up to a maximal of 3 trials The final step is to close the communication with the device read file ini_answer BUF_LEN if write file amp value size_t 1
80. nal driver functions for sending data through the I C bus There are some necessary functions for the correct implementation of the i2c_driver The probe function is the responsible of filling an i2c_adapter structure with the bus number that is known in this case and an i2c_board_info structure with the device address and driver name Then it calls i2c_new_device The attach_adapter checks if any C device is on the I C bus to which the client driver wants to attach In positive case it calls the detect function The detect_client function fulfills the 12c_client data Finally the detach_adapter function is responsible of unregistering the I C device by calling i2c_unregister_device and releasing the memory As final step it can be useful to create a line discipline specific for the thermal camera A line discipline is responsible for implementing the semantics associated with the device Depending on user request it maps the control character to newline converts lowercase to uppercase expands tabs and echoes characters to the associated VT VENKATESWARAN 2008 In the case of the thermal camera it can be used either to attach the CRC code or to actually translate the complicate commands to something easier for the user as the function list in Appendix 3 Each line discipline is identified by a number The line discipline can be implemented as part of the kernel or dynamically load it as a module VENKATESWARAN
81. nits Price unit Total cost HTerm 1 0 00 Freeware 0 00 C Kermit 1 0 00 Freeware 0 00 Total 0 00 3 4 Equipment and tools In order to calculate the attributable cost of the equipment and tools it was considered that the typical amortization period is 4 years and it was distributed in aliquot parts according to hours of work Shipping cost is already considered in Test Environment Linux driver development for components of the UAV based fawn detection system 9 Carmen Eva Ballesteros Gonz lez DOCUMENT II PROJECT BUDGET 3 PARTIAL SUMMATION Element Amount Hours of Hours of Price Amort Cost work project work year unit Computer 1 1000 1600 799 00 25 124 84 Oscilloscope 1 10 300 1 580 00 25 13 17 Multimeter 1 20 300 45 00 25 0 75 Soldering iron 1 30 300 35 00 25 0 88 Solder sucker 1 15 150 35 00 25 0 88 Total 140 52 3 5 Labor Activity Hours Price hour Cost Initial tests 50 12 00 600 00 Programming 300 12 00 3 600 00 Hardware implementation 70 12 00 840 00 Tests and problem solving 150 12 00 1 800 00 Writing documentation 150 12 00 1 800 00 Total 8 640 00 Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez 10 Chapter 4 General budget Adding the contribution of all previous entries the total cost of the project amounts to Entry Cost Final Pr
82. nows which device is being referenced when the later close write and other functions are called This function returns 0 when the opening is a success and a negative value when an error occurs close open and close can be called several times therefore the function should track how many times it has been opened in order to know if it can be closed It can be performed with a counter associated to the tty driver This function has no returning value a write This function is called when there is data from the user space that needs to be sent to the hardware It should use the functions from SMBus to send the data The returned value is the number of characters that was able to be sent Negative numbers indicate an error in the function a write_room Returns the number of characters available in the write buffer Linux driver development for components of the UAV based fawn detection system 51 Carmen Eva Ballesteros Gonz lez I REPORT 3 DEVELOPMENT OF THE LINUX DRIVER octl ioctl is the function called for executing operations which are not represented by other function calls It becomes as second parameter a code number representing the action to perform and as third parameter either an integer value or a pointer with the necessary data for the action It can be used for implementing a special line discipline in the driver set_termios Termios is the struct in the tty_driver that handles the communication par
83. o mlr100 g 2 04m Appendix 4 contains a list with all the commands that the laser distance sensor application accepts Another command that can be tested is the one setting the power mode The only way to make sure which power mode is set is by measuring the power and comparing the energy consumption in both power modes The energy consumption can be calculated either using a wattmeter or measuring the voltage as well as the current and multiplying them Linux driver development for components of the UAV based fawn detection system 58 Carmen Eva Ballesteros Gonz lez Chapter 5 Conclusion and outlook The main scope of the master thesis was to develop a software capable of establishing a communication with the serial port of the thermal camera and the laser distance sensor Physically the communication flows from the serial port of the device to an interface that converts from UART to I C The interface is then connected to the computer on module through an I C bus Figure 5 1 represents this connection UART 12C Bus RX Figure 5 1 Connection between the COM and the devices through the SC16IS740 interface The first section of the chapter analyzes the product developed during this project The second section contains possible improvements of the product that can be done in future developments 5 1 Analysis of the developed software The driver shall be able to communicate with the thermal camera and the dist
84. o para configurar la c mara t rmica y obtener las medidas del sensor de distancia que lleva a bordo el octoc ptero Tanto la c mara como el sensor pueden conectarse a trav s del puerto serie El ordenador a bordo no cuenta con m s puertos serie disponibles Sin embargo cuenta con un bus I C que admite hasta 128 dispositivos conectados Para llevar a cabo dicha conexi n es necesario usar una interfaz que haga la conversi n UART IC El dispositivo usado es el chip SC16IS740 2 En la Figura 1 2 se destaca tanto la conexi n entre la c mara t rmica IR Camera y el ordenador a bordo Computer On Module como la conexi n entre el sensor de distacia LDS y el ordenador Ambas conexiones se realizan mediante el conversor UART IC Digital Video Level Shifter P Digital Video Console uart en Port PC master Computer On Module GPIOs TV Out Y Power Level Supply Shifter I RS232 Backup Tranceiver ack u UART LE st r En FEDER ter I Y Y Falcon 8 Connector Figura 1 2 Diagrama de las conexiones entre los diversos dispositivos y el ordenador a bordo del octoc ptero destacando los componentes importantes para el software desarrollado para el proyecto El ordenador a bordo usa como sistema operativo Gumstix Overo Series que incluye un kernel Linux Debido a que no hay drivers disponibles para la interfaz SC16IS740 en Linux el software desarrollado en el proyecto debe incluir un d
85. oduct 14 272 99 Testing environment 70 86 Software 0 00 Equipment and tools 140 52 Labor 8 640 00 Total 23 124 37 Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez 11
86. on config inside the driver This function is called from open that belongs to the struct file_operations of the char_driver Open is called from the user space when opening the device and it is mostly used to store important data of the driver in the variable file The code of the function config is static void config struct file xfilep Linux driver development for components of the UAV based fawn detection system 67 Carmen Eva Ballesteros Gonz lez II USER MANUAL 1 HOW TO CONFIGURE THE SETTINGS OF THE SERIAL PORT IN THE DRIVER char datal2 struct scl6is740 my_sc struct scl6is740 filep gt private_data data 0 0x18 data 1 0x80 i2c_smbus_write_byte_data my_sc gt client data 0 data 1 As brief explanation about the code one of the components in struct sc 16is740 is an 12c_client While implementing the i2c_driver in the kernel an i2c_client was created This client is necessary in all SMBus functions therefore it is saved within the struct file in order to be able to retrieve the data in all file_operations functions The function i2c_smbus_write_byte_data receives as second argument the register address and as third the byte that must be written in the aforementioned register Linux driver development for components of the UAV based fawn detection system 68 Carmen Eva Ballesteros Gonz lez Chapter 2 How to create an application for the driver First of all the applic
87. on to another computer on the ground From this computer it is also possible to observe the images taken by the cameras in real time This is useful not only to corroborate the detection of the animals but also for checking that the image taken by the infrared camera is valid for the analysis This image depends on the weather conditions and it is usually necessary to readjust the parameters of the camera during the flight 1 1 2 Assigned task The task of this master thesis consists in developing the necessary drivers that enables the communication between the Computer On Module and the thermal camera and between the Computer On Module and the laser distance sensor The thermal camera as well as the sensor can communicate through a serial port The Computer On Module has no more serial ports availables However it has a I C bus that admits up to 128 IC devices connected In order to establish this connection it is necessary to add a UART I C converter The chosen interface is the chip SC16IS740 2 Figure 1 6 shows the connections between the components and the computer in the expansion board and emphasizes the important connectios for the developed software Digital Video Invert Digital Video Console Port PC master GPIOs TV Out Supply RS232 a ao Tranceiver ackuf UART LED Taster Battery 5 Be en Falcon 8 Connector Figure 1 6 Connection between the COM and both the thermal came
88. por la c mara tras cambiar el contraste a los valores 20 50 y 70 El funcionamiento de la aplicaci n del sensor se comprob tomando medidas con el sensor conectado al ordenador a bordo Todas las pruebas fueron satisfactorias comprobando que la aplicaci n funciona A continuaci n se muestra un ejemplo del funcionamiento de la aplicaci n root overo mlr100 g 2 04m 1 4 Conclusiones El objetivo del proyecto es desarrollar el software necesario para controlar la c mara t rmica y el sensor de distancia que lleva a bordo el octoc ptero Dicho objetivo se complet desarrollando para cada dispositivo un driver que controle directamente el hardware y una aplicaci n que interact e con el usuario y maneje el driver Referencias 1 Jarnemo A 2002 Wildlife Biology vol 8 Roe deer Capreolus capreolus fawns and mowing mortality rates and countermeasures 2 SC1615740 750 760 Single UART with I2C bus SPI interface 64 bytes of transmit and receive FIFOs IrDA SIR built in support NXP Semiconductors 3 Venkateswaran Sreekrishnan 2008 Essential linux device drivers Prentice Hall Linux driver development for components of the UAV based fawn detection system IX Carmen Eva Ballesteros Gonz lez RESUMEN Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez LINUX DRIVER DEVELOPMENT FOR COMPONENTS OF THE UAV BASED FAWN DETECTION SYSTEM 1 1 Introduction
89. pter my_sc16is740 gt client gt flags 0 strlcpy my_scl6is740 gt client gt name DEVICE_NAME I2C_NAME_SIZE lt ne return SUCCESS The detach_adapter function is called when the device is unbound and is responsible of unregistering the I2C device by calling i2c_unregister_device and releasing the memory static int scl6is740_detach struct i2c_adapter adapter kfree adapter return SUCCESS On the other side there is the struct file_operations controlling the device as if it were a file Its functions must be defined as well and they will be call directly from the user space During the open function first the module usage count is incremented to protect against removal then the important information is stored in the private_data ofthe opened file and the UART configuration for the chip explained in Section 3 1 3 is set The function config is detailed in Appendix 1 Linux driver development for components of the UAV based fawn detection system 46 Carmen Eva Ballesteros Gonz lez I REPORT 3 DEVELOPMENT OF THE LINUX DRIVER static int my_open struct inode xinode struct file filep int Minor inode gt i_rdev OxFF try_module_get THIS_MODULE filep gt private_data struct scl6is740 my_scl6is740 config filep return SUCCESS Inthe close function the module count is decremented static int my_rele
90. ra and the laser distance sensor The Computer On Module uses Gumstix Overo Series as operating system that already includes a Linux kernel As there is no driver for the SC1615740 in Linux it is necessary to develop a driver to manage the interface and include it in the software Linux driver development for components of the UAV based fawn detection system XII Carmen Eva Ballesteros Gonz lez RESUMEN 1 2 Methodology In monolithic kernels as Linux the kernel runs in kernel mode and the applications in user mode Any subroutines or functions forming part of the kernel modules and device drivers for example are considered to be part of kernel space End user programs are part of the user space When these applications need to interact with the system s hardware they don t do so directly but through the kernel supported functions 3 The required software musts act like bridge between the user and the corresponding device Therefore it has been established that the software will be split in two parts a module driver in the kernel space to configure the serial port of the UART amp PC converter and to control the device an application in the user space to interact with the user personalized for each device Hereafter follows an explanation of the development of the software 1 2 1 Development of the linux driver For this certain situation there are two important structures required in the driver On the one
91. rateful to Dr Ing Peter Haschberger for his supervision and valuable advice I wish to extend my sincere gratitude to Dipl Ing Philipp Neugebauer and all preceding graduate students for their previous work that made possible the development of my master thesis I am grateful to DLR and specially the Institut f r Methodik der Fernerkundung that provided the support and equipment I needed to produce and complete my work Lastly I would like to show my gratitude to my colleagues and staff in DLR for the use of facilities in the Lab and for providing a friendly environment for working a coffee machine and moral support Linux driver development for components of the UAV based fawn detection system XIX Carmen Eva Ballesteros Gonz lez ACKNOWLEDGEMENTS Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez XX DOCUMENT I REPORT DOCUMENT I REPORT 2 INDEX Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez Index I Report 11 1 Introduction 13 1 1 Problem situation and motivation 2 2 2 CC on nn 13 1 2 Previous methods of resolution 12 22 4 ee Pee Felle laa 13 1 3 UAV based fawn detection system 2 2 2 2 2 Comm 17 1 3 1 Octocopter platform u 2 Gk w al Se OE OE a OR 17 1 3 2 Hardware components aooaa 18 LSO SOlware Pa ee A AO DEI O ed O Vives 21 1 4 As
92. rform it Another option is to create a new application specific for the device Again the driver in kernel space might need to be modified in order to update the new configuration for the serial port A guide to build an application for the driver is detailed in Appendix 2 and Appendix 1 explains how to configure the serial port at the SC161S740 The last option to solve this problem is to develop a new generic terminal driver for the SC161S740 as explained in section 3 3 Since the driver contains a tty_driver the device can be accessed using a terminal program see section 2 2 1 Therefore it is not necessary to develop an application in order to establish a communication with the device Linux driver development for components of the UAV based fawn detection system 61 Carmen Eva Ballesteros Gonz lez I REPORT 2 REFERENCES Linux driver development for components of the UAV based fawn detection system Carmen Eva Ballesteros Gonz lez 62 References SMB 2000 2000 System Management Bus SMBus Specification Version 2 0 Intel Corporation Gum 2004 2011 2004 2011 Setting up a Serial Connection Gumstix http gumstix org connect to my gumstix system html PCA 2007 2007 PCA9517 Level translating I2C bus__ repeater NXP http www nxp com documents data_sheet PCA9517 pdf Aer 2009 2009 Aerius MLR PC Control Software Aerius Photonics LLC TTL 2010 2010 TTL 232R PCB TIL
93. river capaz de manejar dicha interfaz Linux driver development for components of the UAV based fawn detection system VI Carmen Eva Ballesteros Gonz lez RESUMEN 1 2 Metodolog a En kernels monoliticos como Linux tanto el kernel como todas las subrutinas encargadas de manejar directamente el hardware se ejecutan en el llamado kernel space Las dem s aplicaciones encargadas de interactuar con el usuario se ejecutan en el llamado user space Estas aplicaciones s lo pueden interaccionar con el hardware mediante las funciones provistas a trav s del kernel space 3 El software requerido debe actuar como puente entre el usuario y el dispositivo que quiera controlar ya sea la c mara como el sensor De esta manera es necesario desarrollar dos tipos distintos de software para cada dispositivo Por un lado es necesario desarrollar un driver que env e mensajes a trav s del bus IC configure y controle el conversor UART IC a Por otro lado hay que desarrollar una aplicaci n personalizada para cada dispositivo que controle los mensajes que se le env an lea la respuesta y se la haga llegar al usuario A continuaci n se explica el desarrollo de ambos tipos de software 1 2 1 Desarrollo del driver en kernel space El driver cuenta con dos partes importantes Por un lado para proveer las funciones para el user space necesita contener un character driver Por otro lado debe comunicarse con el dispos
94. rom the camera To run the test it was chosen a command that also requests for information Let s remember first the Serial Packet Protocol It starts with the Process Code 0x63 followed by a sequence of bytes each of them representing a specific feature of the final order Byte 1 2 3 4 5 6 7 8 N N N Upper Process Status Reserved Function Byte CRC1 Data CRC2 Byte Code Code Count In the TAU640 User Manual Tau October 2010 there is a table with all the functions allowed its corresponding Function Code FC Byte Count BC and admissible range of data Taking as example the function that gets the optimization image mode called AGC_TYPE its Function Code is 0x13 and the Byte Count is 0 The first argument sent to the application called configtau640 consists in the message until the first CRC i e bytes 1 to 6 Conforming the message as seen above it results 6E00001300 Byte Count indicates the amount of data bytes In this case as there are no data bytes sent BC is 0 the second argument sent to configtau640 is 0 root overo configtau640 6E00001300 00 Sent 6e 0 013 0 0c588 0 0 Answer 6e 0 013 0 2e5ca 0 22042 According to the User Manual the answer received indicates that the status of the camera 1s ready the FC is 0x13 AGC_TYPE and the answer contains 2 data bytes The data bytes Linux driver development for components of the UAV based fawn detection
95. rt of kernel space User space End user programs are part of the user space Obviously these applications need to interact with the system s hardware However they don t do so directly but through the kernel supported functions The way the developed software interacts in both spaces is shown in Fig 3 5 Hereafter follows the development of the necessary software in kernel space and user space 3 2 1 Character Driver in kernel space This section focuses in explaining the development of the software in kernel space This software must act as a bridge between the hardware and the application For this purpose a character driver that acts like a module device driver was developed In Linux a module device driver can be loaded and unloaded into the kernel using the user commands insmod and rmmod that use respectively the kernel space functions module _init andmodule_exit The function _init is the responsible for performing some preliminary tasks like reserving RAM initializing the device and seamlessly tying the driver to the rest of the kernel via registration functions For this certain situation there are two important structures required in the driver On the one hand the struct file_operations is typically used to manipulate files As in UNIX or Linux systems the devices are seen as files that can be open closed written and read it will be used in this case to manipulate the device On the other hand it is needed an i2c_
96. s Linux driver development for components of the UAV based fawn detection system 55 Carmen Eva Ballesteros Gonz lez I REPORT 4 RESULTS A Ready M Pos 1 000ms TRIGGER Typ Flanke Quelle CH4 Modus Normal Kopplung M 250 us CH4 A 880mY CH4 1 00 29 Mar 12 00 13 lt 10Hz Figure 4 4 Oscilloscope measure at the pin 6 of the SC16IS740 chip while configuring the serial port of the interface Eile Options View Help Disconnect Port dev ttyUSB3 v R Baud 57600 Data 8 v Stop 1 v Parity None v U CTS Flow i rx 48 Reset Tx O Reset Count 0 sl 308 Reset Newline at CR LF v Q oE PERE Clear received Ascii El Hex Dec Bin Save output C Clear at o 3 pent 12 Ej Autoscrol Sequence Overview Received Data Terminal 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 7 EB Tg 11 Datei Bearbeiten Ansicht Suchen Terminal Hilfe 6E 00 00 18 00 02 15 3B 00 OB Bl 6B root overo configtau640 lut black Sent 6e O 018 O 2153b bb16b Answer 6e 0 018 2153b 0 bb16b POBIEWELBE Selection 96 107 12 Timediff 00 00 00 000 0 3 Input control Input options Clear transmitted E Ascii Hex Dec Bin Send on enter None v Send file DTR RI Type HEX v GE 00 00 18 00 02 15 38 00 08 BI 68 ASend Transmitted data 1 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 History 0 10 Connect to dev ttyUSB3 b 5
97. s taken from the UAV cover an area of 27 meter of diameter This reduces significantly the necessary time to track the whole field Weather conditions determine the optimal moment for harvesting the field Therefore under certain conditions a whole region can be harvested in a few days In this case time is crucial to track as much terrain as possible The UAV plans the flight with the help of a GPS and the Google Maps Elevation API In order to verify the accuracy of the API it is also equipped with a laser distance sensor for measuring the distance to the ground during the flight This is also important because the UAV is programmed to fly always at the same altitude taking as reference the start position In sloping terrains the actual distance to the ground can change as shown in Fig 1 7 and therefore the scale of the image would be different For the image processing it is essential to know the actual scale of the image Linux driver development for components of the UAV based fawn detection system 16 Carmen Eva Ballesteros Gonz lez I REPORT e 1 INTRODUCTION Figure 1 6 Terrain covered by the UAV when flying at an altitude of 50 meters Source ISRAEL 2011a 1 3 UAV based fawn detection system This project is focused in the development of software for the UAV based fawn detection system The vehicle uses as main structure the Octocopter Falcon 8 developed by Ascending Technologies GmbH The core of the detection
98. s that are not collected in the file_operations functions Linux driver development for components of the UAV based fawn detection system 69 Carmen Eva Ballesteros Gonz lez II USER MANUAL 2 HOW TO CREATE AN APPLICATION FOR THE DRIVER The function used for writing is size_t write struct file const char x size_t It takes as first argument the struct file obtained when opening the device Second argument is the data that is going to be sent The last argument contains the size of this data Reading is performed by the function size_t read struct filex charx size_t Again the first argument contains the file The second argument is a pointer to the read data from the FIFO buffer The last argument indicates the amount of data bytes requested The application can receive arguments when loaded In function main argc indicates the amount of argument received argv is a pointer to the aforementioned arguments Other way to communicate with the user is through functions like printf and scanf This way the application receives and works on the data from the user Then it sends orders to the driver in kernel space that finally interacts with the hardware Linux driver development for components of the UAV based fawn detection system 70 Carmen Eva Ballesteros Gonz lez Chapter 3 Commands for the TAU640 camera Beside the commands of table 3 1 there is another available possibility in case the user wants to send manually
99. s to other ports of the COM The SC16IS740 chip converts from UART to C and the COM has still available I C ports Once the chip is integrated in the EB the aim turns to be on the one side to be able to communicate with the devices through the SC16IS740 and on the other side to manage to send commands on an understandable format for the device and to make it easier for the user to control both devices In monolithic kernels as Linux the kernel runs in kernel mode and the applications in user mode Therefore it has been established that the software will be split in two parts a character driver in the kernel space to control the device an application in the user space to interact with the user Figure 3 1 helps to visualize this division USER f USER SPACE y 1 KERNEL SPACE 1 HARDWARE Figure 3 1 Interaction layers between user and hardware There are also other ways to achieve the aim The most considered one was the creation of a terminal driver for the SC161S740 The driver would be developed as a generic driver capable Linux driver development for components of the UAV based fawn detection system 35 Carmen Eva Ballesteros Gonz lez I REPORT 2 3 DEVELOPMENT OF THE LINUX DRIVER of interacting with any SC1615740 interface without depending on the characteristics of the attached device For the user the SC161S740 interface would act like a serial port that needs to be con
100. sed fawn detection system 47 Carmen Eva Ballesteros Gonz lez I REPORT 2 3 DEVELOPMENT OF THE LINUX DRIVER Status Byte Description Value hex 0x00 Function executed 0x01 Camera busy processing serial command 0x02 Camera not ready to execute specified serial command 0x03 Data out of range 0x04 Header or message body checksum error 0x05 Unknown process code 0x06 Unknown function code 0x07 Timeout executing serial command 0x09 Byte count incorrect for the function code 0x0A Function code not enabled in the current configuration Table 3 5 Status Byte return data_left Once the driver is ready the module is inserted in the kernel using insmod As there are two SC161S740 the driver must be duplicated in the kernel space but with small changes like the address the name of the device and the specific configuration required for both attached devices 3 2 2 User Application for the thermal camera TAU640 The thermal camera TAU640 can only recognize commands that follow a specific packet protocol Out coming messages are only sent as response of an incoming command and they also follow the same protocol This Serial Packet Protocol starts with the Process Code 0x63 followed by a sequence of bytes with specific meanings Byte 1 2 3 4 5 6 7 8 N N 1N 2 Upper Process Status Reserved Function Byte CRC1 Data CRC2 Byte Code Code Count The St
101. signment situation and task structuring 2 222 con 22 2 Development of the test environment 25 2 1 Hardware toals oo ow Su ae ch cn a re a a A 25 21 USBC converter aras ee Dr da nel nel 26 2 1 27 WART USB Converter 2 2 o a Be HE A ES 27 22 SoftWaretools so al a d Boke SO p k p dk A A eoi in 28 2 2 1 Communication tools A Sone Re SES A 28 2213 Kermit sr Re EA Er are D el 28 2 2 1222 Herm zuge eg Se a Bra ae a Sun EA a eA 29 2 2 2 TAU640 thermal camera connected to the computer 29 2 2 3 MLR100 laser distance sensor connected to the computer 30 Moa A RR 32 3 Development of the Linux driver 35 3 1 SC1618740 Chip u a a BES a a E Boks 36 Ile DC ae ana RN SR Bait Re RER Oe G 37 Sibila WARD a aves wen E UD E AD WAND BD OAD Yt 40 3 1 3 UART configuration for the SC16IS740 o o o ooo 40 3 2 Development of the specific software for controlling both devices 43 3 2 1 Character Driver in kernel space 00 22 2 bee esse ee ee ee 43 3 2 2 User Application for the thermal camera TAU640 48 3 2 3 User Application for the laser distance sensor MER100 49 3 3 Generic Terminal Driver for SC16IS740 2 2 2 2 ooo o o 50 4 Results 53 41 Preliminary testa Hr 2a ea 2 A E A ER DE AAA AA 53 4 1 1 Tests with the help of an oscilloscope 2 2 22 22mm nennen 53 4 1 2 Tests connecting the EB to the COMPUter 54 4 2 Test connec
102. special format can be found in section 3 2 2 The required configuration of the serial port in the thermal camera is Baud rate 57600 Data bits 8 Parity None Stop bits 1 Flow control None 2 2 3 MLR100 laser distance sensor connected to the computer The sensor is equipped with an Interface Adapter Board that allows UART and RS232 communication see Figure 2 8 The UART interface uses a 3 3V signal but it is 5V tolerant The admissible power supply may vary from 4V to 40V The numbered pins in Fig 2 8 are detailed in Table 2 2 The connection with the computer was achieved connecting pins 1 to 3 to the RS232 port of the computer and the power supply was obtained from a USB port Linux driver development for components of the UAV based fawn detection system 30 Carmen Eva Ballesteros Gonz lez I REPORT 2 2 DEVELOPMENT OF THE TEST ENVIRONMENT File View Camera Tools Help SFLIR File View Camera Tools Help y E Status Orientation Polarity LUT Status J Invert Flip the image vertically OTE m Revert Flip the image horizontally 3 Algorithm m Linear Parameters 7 Setuy Pan amp Zoom FFC a Automatic d Setup O Contrast O Unzoom FFC Warning 10 Frames O Once Bright O Zoom 2x u O Auto Bright Video O zoom 4x Video O Manual 0 gt Zoom 8x 32 a Dynamic DDE a O Linear Histogram P Ga Pan 60 7 AGC Brightness Fine C
103. system 57 Carmen Eva Ballesteros Gonz lez I REPORT 4 RESULTS conforming 0x0002 has the meaning according to the manual that the optimization image mode set on the camera is the one denominated auto bright Another performed test consists in sending a certain command that changes the parameter of the image One function that is easily detected at first sight is the contrast function Figure 4 6 helps to visualize the difference between three different contrast values in the image captured by the camera root overo configtau640 contrast 100 Sent 6e 0 014 0 2605a 0642c22 Answer 6e 0 014 0 2605a 0642c22 Figure 4 6 From left to right captured image with contrast 20 50 and 70 4 2 2 Test connecting EB to MLR100 Opposite to the thermal camera the effectiveness of the application for the laser distance sensor cannot be visualized Fortunately the main reason the software for the sensor is developed for is to obtain the distance measure Checking the correct operation of this feature is enough to consider that the application works The test was carried out by assembling the laser to the EB inserting the driver and using the application to ask for the measured distance Knowing the real distance in advance the next step 1s to compare it to the given answer As example the sensor was positioned 2 meters away from a wall pointing directly to it The following code was the result of executing the application root over
104. system is a small computer on module COM which takes over the data processing A thermal and a RGB camera are the main sensors attached to the system In general all sensors are connected to the COM through an expansion board EB Hereafter follows a more detailed description of the components 1 3 1 Octocopter platform The platform of the UAV is an octocopter system developed by Ascending Technologies GmbH The called Falcon 8 model is specially designed for air photography and to inspect and get data during the flight The model flying can be seen in Fig 1 8 The eight actuators combination of rotor and motor give the UAV a high stability and skill to hold winds with a maximal speed of 10 m s The stability is reinforced by an integrated control system using the measures of multiple electronic sensors like a GPS gyroscope barometric height sensors compass and velocity sensors http www asctec de Linux driver development for components of the UAV based fawn detection system 17 Carmen Eva Ballesteros Gonz lez I REPORT 1 INTRODUCTION Constant flight altitude Start position Figure 1 7 The flight plan of the UAV is designed to fly always at the same altitude taking as reference the start position In sloping terrains this affects to the image processing as the scale changes Source ISRAEL 2011a Figure 1 8 Falcon 8 model flying over a field Source ISRAEL 2011b The octocopter includes a
105. t terminal programs were used In order to access the COM and load the Gumstix Overo System Kermit 2 2 1 1 was chosen because of recommendation for the Gumstix Over System During the tests the communication with the other devices connected to the computer was established using a GUI application For this project HTerm 2 2 1 2 was chosen 2 2 1 1 Kermit Kermit is a computer file transfer management protocol and a set of communications software tools that provides a consistent approach to file transfer terminal emulation script programming and character set conversion across many different computer hardware and almost every OS platform COLUMBIA UNIVERSITY COMPUTER CENTER 2011 Linux driver development for components of the UAV based fawn detection system 28 Carmen Eva Ballesteros Gonz lez I REPORT amp 2 DEVELOPMENT OF THE TEST ENVIRONMENT It was used to load the Gumstix Overo and manipulate it from the personal computer But first it is necessary to set manually the serial configuration In GNU Linux it can be easily done by saving the following commands in a file and then executing it Gum 2004 2011 usr bin kermit kermit 1 dev ttyUSBO set speed 115200 set reliable fast set carrier watch off set flow control none set prefixing all set file type bin set rec pack 4096 set send pack 4096 set window 5 connect The above code defines dev ttyUSBO as the location of the device This lo
106. ting EB to the actual devices o a 56 4 2 1 Test connecting EB to TAU649 3 a Ror eS eee a 57 4 2 2 Test connecting EB to MLR100 o 58 Linux driver development for components of the UAV based fawn detection system 3 Carmen Eva Ballesteros Gonz lez DOCUMENT I REPORT 2 INDEX 5 Conclusion and outlook 59 5 1 Analysis of the developed software 59 5 2 Possible future improvements 2 2 2 Comm 60 References 62 II User Manual 65 1 How to configure the settings of the serial port in the driver 67 2 How to create an application for the driver 69 3 Commands for the TAU640 camera 71 4 Application for the laser distance sensor MLR100 73 Linux driver development for components of the UAV based fawn detection system 4 Carmen Eva Ballesteros Gonz lez List of Figures 1 1 Geometrical conditions in the search of deer fawn To find it the person must be in a close proximity from 1 to 2 meters Source ISRAEL 201la 14 1 2 People carrying the portable rescue system Source HARDER 2008 15 1 3 Design of mower with extension arm Source ISRAEL 2010b 15 1 4 Testing model of extension arm incorporated in mower Source ISRAEL 2010a 15 1 5 Principle of the double radar Source A FACKELMEIER 2009 16 1 6 Terrain covered by the UAV when flying at an altitude of 50 meters Source IISRAELS20TA veta tt ta ks o a o
107. trical conditions in the search of deer fawn To find it the person must be in a close proximity from 1 to 2 meters Source ISRAEL 2011a In order to locate those animals before the mowing the German Aerospace Center DLR through the Remote Sensing Technology Institute is developing several systems aimed to scan an area looking automatically for the fawns ISRAEL 2010a Portable rescue system DLR developed and patented a portable rescue system in 1987 Ten years ago it was introduced in the market by i_s_a The rescue system consists of a telescopic handle that thanks to ten infrared sensors can be used to cover a width of six meters as shown in Fig 1 2 This system can quickly scan the closer ground On cloudy days or during the early morning and late evening the system works with a high reliability On the other hand with a strong sunlight the sensors will be limited and fawns can no longer be distinguished from other objects such as mounds or molehills distribution by isa Industrieelektronik GmbH www isaweiden de www wildretter de Linux driver development for components of the UAV based fawn detection system 14 Carmen Eva Ballesteros Gonzalez I REPORT 1 INTRODUCTION Figure 1 2 People carrying the portable rescue system Source HARDER 2008 Extension arm sensors at the mowing machine More recent developments and researches engage in adding appropriate sensors directly to the agricultural m
108. uired what results with a prescaler of 1 a baud rate of 56000 Bd with an error difference of 2 86 this makes the desired 57600 Bd Before setting the divisor in the SC161S740 it is necessary to enable the divisor latch first by setting the bit 7 of the register LCR 0x3 at high logic and then writing the LSB of the divisor at register DLL 0x0 and the MSB at DLH 0x1 As the prescaler stays with its default value 1 it is not necessary to set it According to Table 3 4 in SC16IS740 the register address for LCR is 0x18 the one for register DLL is 0x00 and the address for DLH is 0x08 Bit 71 6 514 3 2 1 10 Value A3 A2 Al AO CH1 CHO DLL Ox0 0 0 0 O 0 0 O 0 0x00 DLH 0x1 0 0 0 O 1 0 O 0 0x08 FCR 0x2 0 0 O 1 0 0 O 0 0x10 LCR 0x3 0 0 O 1 1 0 0 0 0x18 Table 3 4 This table set the register address of the different registers used in this section according to table 3 2 and the register id In section 3 1 1 it was established that the address for the SC16IS740 connected to the camera is 1001 001 R W As the aim now is to write in the registers and W takes the value 1 in order to Linux driver development for components of the UAV based fawn detection system 41 Carmen Eva Ballesteros Gonz lez I REPORT amp 3 DEVELOPMENT OF THE LINUX DRIVER indicate that the master is writing the address of the slave in hexadecimal is 0x92 As section
109. ware e 35 3 2 The aim of the generic driver is that the user can communicate through it as it were a serial port The user would interact with the attached device using a communication tool see section 2 2 1 that needs to be configured for the certain device attached to the chip The developed driver is specified for the attached device and manages it in an optimal way The user interacts directly with the device through the application 36 3 3 Pin configuration for TSSOP16 with PC bus interface 37 3 4 Connection between COM SC1615740 chips and the corresponding devices 37 3 5 Global diagram of the interaction of the different layers in the developed software both in kernel and User space 4 24 2 tn ai a 44 3 6 Diagram of the driver in kernel Space 2 2 Em nn 44 Linux driver development for components of the UAV based fawn detection system 5 Carmen Eva Ballesteros Gonz lez DOCUMENT I REPORT INDEX OF FIGURES 3 7 Global diagram of the different tools interacting in the generic driver for SC16IS740 51 41 Loading the Gumstix Overo System aan 2 aaa a e 54 4 2 General view of the back side of the Expansion Board Source NEUGEBAUER 2011 55 4 3 General view of the front side of the Expansion Board Source NEUGEBAUER 2011 55 4 4 Oscilloscope measure at the pin 6 of the SC16IS740 chip while configuring the serial Port of theanterfaee is ae ee PES ERs 56 4 5 Hterm and a female B
110. ytes of the packet CRC2 is calculated from all previous bytes bytes 1 to N A list with all available commands for the camera and their valid arguments are shown in Appendix 3 Commands for the TAU640 camera Not all possible functions were implemented because they were not considered relevant for the control of the camera on the octocopter Actually there is still one other possibility not shown in table 3 1 in appendix 3 in case the user wants to send manually a command It consists in sending to the application as first argument the first part of the command up to CRCI and as second argument the data again without the CRC2 code The application generates both omitted CRC codes and sends the command to the camera The purpose of this option is to let the sending of commands that are not implemented in the program exempting the user from calculating both CRC Transmission is LSB first for each byte and most significant byte first on multi byte messages All bytes are preceded by a zero start bit and followed by a one stop bit For example when sending 6E the bits should follow the sequence 0 0111 0110 1 this is Start bit E with LSB first 6 with LSB first Stop bit The software in user space can interact with some functions implemented in the kernel space of the driver In this case the functions are open read write and close First 1t generates the command verifying that the arguments make sense and there is no error Once the

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