EFM32 Getting Started - AN0009 - Application Note
Contents
1. ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Register Operation 2 2 Register Description The EFM32 EZR32 and EFM32 Gemstones devices use a 32 bit bus for write read access to the peripherals and each register in a peripheral contains 32 bits numbered 0 31 Unused bits are marked as reserved and should not be modified The bits used by the peripheral can either be single bits e g OUTEN bit in the figure below or grouped together in bitfields e g PRSSEL bitfield in the figure below Each bitfield is described with the following attributes e Bit position Name e Reset value e Access type e Description 24 5 1 IDAC_CTRL Control Register Offset Bit Position oo 5 8 ala slela alalsls alele s 2le s 2 e e 2 o ol lolols ola le e ee ee wos e eff a 2 amp m 2 o 5 2 2 Name E ES 2 Fis a 4 x Z Eja E z 5 Z 5 JGS 5 2 E o lt a lt olja Bit Name Reset Access Description 31 24 Reserved To ensure compatibility with future devices always write bits to 0 More information in 1 2 Conven tions 23 20 PRSSEL 0x0 RW IDAC Output PRS channnel Select Selects which PRS channel to use when OUTENPRS is set Value Mode Description 0 PRSCHO PRS Channel 0 selected 1 PRSCH1 PRS Channel 1 selected 2 PRSCH2 PRS Channel 2 selected 3 PRSCH3 PRS Channel 3 selected 4 PRSCH4 PRS Channel 4 selected 5 PRSCH5 PRS Channel 5 selected 6 PRSCH6 PRS Channel 6 selected 7 PRSCH7 PRS Channel2. 2 Register Operation This chapter explains the basics of how to write C code for the EFM32 devices using the defines and library functions supplied in the CMSIS and emlib software libraries 2 1 Address The EFM32 EZR32 and EFM32 Gemstones devices consist of several different types of peripherals CMU RTC ADC Some pe ripherals in the device exist only as one instance like the Clock Management Unit CMU Other peripherals like Timers TIMERn exist as several instances and the name is postfixed by a number n denoting the instance number Usually two instances of a peripheral are identical but are placed in different regions of the memory map However some peripherals have a different feature set for each of the instances For example USARTO can have an IrDA interface while USART1 cannot Such differences will be explained in the de vice data sheet and the reference manual Each peripheral instance has a dedicated address region which contains registers that can be accessed by read write operations The peripheral instances and memory regions are found in the device data sheet The starting address of a peripheral instance is called the base address The reference manual for the device series contains a complete description of the registers within each peripheral The address for each register is given as an offset from the base address for the peripheral instance silabs com Smart Connected Energy friendly Rev 1 19 2
3. AtssaessaasessaneassnaessanseessEueetEee442400555000424000420005 5800048400088 m file 1 registers c Files 7 paige a a N sabes 0x00000000 HAPSR 0x60000000 B em_gpox_st ather Backus iicr 2S R1 OxFFFFFE00 HIPSR 0x00000000 Gemsis ion 1 17 R2 0x00989667 HEPSR 0x01000000 Genlib Eea LATER SEER EEE R SERRE EERE EEE EEEEREEEREEERESE SEES SREES SEER REEER EEE RERERERE R3 Oxo0000000 PC 0z000002EA nse R4 0x000000FF HPRIMASK Ox00000000 R O O ight 2013 Energy Micro AS LEER penis R5 0x0000003A fBASEPRI 0x00000000 FEEEEEEREEE SEER EEEEERERERER ESSERE EEE EEEEREREREEEREREEEEEEEEEEEEE R6 Ox00000000 fBASEPRI_MAX 0x00000000 eae R7 Ox00000000 HFAULTMASK 0x00000000 Permission is granted to anyone to use this software for any purpose including commercial applications and to alter it and redistribute i R8 0x00000000 EICONTROL 0x00000000 freely subject to the folloving restrictions R9 Ox00000000 CYCLECOUNTER 52 R10 0x00000000 1 The origin of this softvare must not be misrepresented you must not R11 0x00000000 claim that you vrote the original softvare R12 0x200009CC 2 Altered source versions must be plainly marked as such and must not be SP Ox20000400 misrepresented as being the original software LR 0x0000070F 3 This notice may not be removed or altered from any source distribution The source and compiled code may only be used on Energy Micro EFM32 Disassembly x microcontrollers and EFR4 radios Raa M
4. Consult the user guide for information specific to the kit in use Looking into the available functions for the GPIO the following function can be used to configure the mode of the GPIO pins void GPIO_PinModeSet GPIO_Port_TypeDef port unsigned int pin GPIO_Mode_TypeDef mode unsigned int out Use this function to configure the LED pin s as Push Pull outputs with the initial DOUT value set to 0 silabs com Smart Connected Energy friendly Rev 1 19 11 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Example 2a Blinking LEDs with an STK 4 3 Step 3 Configure a GPIO Pin for a Button Look at the User Manual for the STK to find where Push Button 0 PBO is connected on the kit in use This button is connected on several example kits as follows e EFM32 Gxxx STK Port B pin 9 e EFM32TG STK3300 Port D pin 8 e EFM32GG STK3700 Port B pin 9 e EFM32ZG STK3200 Port C pin 8 Configure this pin as an input to be able to detect the button state 4 4 Step 4 Change LED Status when a Button is Pressed Write a loop that toggles the LED s every time PBO is pressed Make sure to not only check that the button is pressed but also that it is released so that the LED s only toggle once for each button press PBO is pulled high by an external resistor 4 5 Extra Task LED Animation Experiment with creating different blinking patterns on the LED s like fading and running LEDs if there are multiple
5. but not limited to nuclear biological or chemical weapons or missiles capable of delivering such weapons Trademark Information Silicon Laboratories Inc Silicon Laboratories Silicon Labs SiLabs and the Silicon Labs logo CMEMS EFM EFM32 EFR Energy Micro Energy Micro logo and combinations thereof the world s most energy friendly microcontrollers Ember EZLink EZMac EZRadio EZRadioPRO DSPLL ISOmodem Precision32 ProSLIC SIPHY USBXpress and others are trademarks or registered trademarks of Silicon Laboratories Inc ARM CORTEX Cortex M3 and THUMB are trademarks or registered trademarks of ARM Holdings Keil is a registered trademark of ARM Limited All other products or brand names mentioned herein are trademarks of their respective holders Silicon Laboratories Inc 400 West Cesar Chavez Austin TX 78701 USA SILICON LABS
6. LEDs Because the device typically runs in the 14 MHz range by default add a delay function to be able to see the LEDs changing in real time Using the code for TIMERO in Example 1 create the following function void Delay uint16_t milliseconds Use the PRESC bitfield in TIMERO_CTRL to reduce the clock frequency to a desired value silabs com Smart Connected Energy friendly Rev 1 19 12 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Example 2b Blinking LEDs with a DK 5 Example 2b Blinking LEDs with a DK Use a Development Kit to run this example The aim is to use the GPIO pins to light up the LEDs on the DK and change the LED configuration every time the joystick is moved The AN0009 application note includes a lt kit_name gt _2_leds example in Simplicity Studio and the IAR efm32 workspace contains a project called lt kit_name gt _2_leds which will be used in this example 5 1 Board Support Library The Development Kits use a board controller to configure the functions of the development kit including lighting the user leds and read ing buttons joystick These functions can be controlled by the MCU device by communicating with the board controller via either SPI or External Bus Interface The device can then configure the registers in the board controller to set up the functions wanted The Board Support Library includes drivers for handling access to the DK An initialize function must be run fi
7. interrupt after 5 seconds First enable the clock to the RTC by using the CMU emlib functions To communicate with Low Energy Frequency peripherals like the RTC also enable the clock for the LE interface CmuClock_CORE The emlib initialization function for the RTC requires a configuration struct as an input volo BIC Init const BICLinit_Typeber inie The struct is already declared in the code but firmware must set the 3 parameters in the struct before using it with the RTc_Init func tion rtcInit compOTop true Next set compare value 0 COMPO in the RTC which will set interrupt flag COMPO when the compare value matches the counter value Chose a value that will equal 5 seconds given that the RTC runs at 32 768 kHz void RTC_CompareSet unsigned int comp uint32_t value Now the RTC COMPO flag will be set on a compare match but the corresponding enable bit must also be set to generate an interrupt request from the RTC void RTC_IntEnable uint32_t flags The RTC interrupt request is enabled on a comparator match but to trigger an interrupt the RTC interrupt request line must be enabled in the Cortex M The IRQn_Type to use is RTC_IRQn NVIC_EnableIRQ RTC_IRQn An interrupt handler for the RTC is already included in the code RTC_IRQHandler but it is empty In this function add a function call to clear the RTC COMPO interrupt flag If firmware does not do this the Cortex M will be stuck in the interrupt handler sinc
8. left pane to place a breakpoint before firmware starts the timer and click the Resume button Then watch the RUNNING bit get set to 1 in the Registers view when single stepping over the expression using the Step Over button Continue to single step and note that the content of the CNT registers is increasing Try writing a different value to the CNT register by entering it directly in the Registers view Build and Debug Resume Step Over Registers View Expressions View pe sat Debug STKXXX_blink src blinkc File Edt Source Refactor to Die 5 5 Debug 53 Variables Breakpoints biai Registi gt ET ss 4 Slicon Labs ARM MCU EFM32G8S0F128 adapter si B na a I STOO biinkaxt main at bink c50 Ox3t4 Name Value Description 2 m n M General General Purpose Registers Disconnect TA 4 tio AES AES otoi CTRL 0x0 Control Register o CMD 0x0 Command Register 4 m No details to display for the current selection E Lregistersc biinke 32 DE Outline 3 int main void a GULKY int count i stdinth l stdboolh Chip errata Gl em_deviceh CHIP_Init em chip h aJ bsph Double click to i Ensure core frequency has been updated U preh SystemCoreClockUpdate V msTicks volatile uint32 t add a breakpoint E msTicks volatile uint32_t If first word of user data page is non zero ena
9. 7 selected 8 PRSCH8 PRS Channel 8 selected 9 PRSCH9 PRS Channel 9 selected 10 PRSCH10 PRS Channel 10 selected 11 PRSCH11 PRS Channel 11 selected Figure 2 1 Example Register Description silabs com Smart Connected Energy friendly Rev 1 19 3 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Register Operation 2 3 Access Types Each register has a set access type for all of the bit fields within that register The access types describes the reaction to read or write operation to the bit field The different access types found for the registers in the devices are described in the table below Table 2 1 Register Access Types Access Type Description R Read only Writes are ignored RW Readable and writable RW1 Readable and writable Only writes to 1 have effect w1 Read value undefined Only writes to 1 have effect W Write only Read value undefined RWH Readable writable and updated by hardware 2 4 CMSIS and emlib The Cortex Microcontroller Software Interface Standard CMSIS is a common coding standard for all ARM Cortex devices The CMSIS library provided by Silicon Labs contains header files defines for peripherals registers and bitfields and startup files for all devices In addition CMSIS also includes functions that are common to all Cortex devices like interrupt handling intrinsic functions etc Although it is possible to write to registers using hard coded addres
10. Documentation Click to open Application Notes Cactew BA Arida Figure 1 1 Application Notes Tile in Simplicity Studio Within the Application Notes dialog navigate to and select the AN0009 Getting Started with EFM32 entry then click the Import Project button to view the list of available example projects Use the project names to identify examples compatible with the kit and select one to import that project into the IDE by default this is the Simplicity Studio IDE but this configuration can be changed to an alternative IDE if desired Alternatively projects for multiple IDEs are stored in separate folders iar arm etc in the filesystem that hosts these examples ac cessible with the Open Folder button in the Simplicity Studio Applications Notes dialog These projects can be manually loaded in the appropriate IDE All of the IAR projects are also collected in one common workspace called efm32 eww Since the projects are slightly different for the various kits make sure to open the project that is prefixed with the name of the kit in use Note The code examples in this application note are not complete and the reader is required to fill in small pieces of code throughout the exercises A completed code file postfixed with _solution c also exists for each example silabs com Smart Connected Energy friendly Rev 1 19 1 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Register Operation
11. OUT 0x0000 RW Data Out Data output on pin Figure 2 2 Grouped Registers in GPIO In the CMSIS defines the port registers are grouped in an array P x When using this array we must index it using numbers instead of the port letters A 0 B 1 C 2 Accessing the DOUT register for port C can be done like this GPIO gt P 2 DOUT 0x000F silabs com Smart Connected Energy friendly Rev 1 19 6 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Example 1 Register Operation 3 Example 1 Register Operation This example will show how to write and read registers using the CMSIS defines This tutorial also shows how to observe and manipu late register contents through the debugger in Simplicity Studio or IAR Embedded Workbench While the examples are shown only for Simplicity Studio and IAR the tasks can also be completed in other supported IDEs For Simplicity Studio 1 Connect the kit to the PC 2 Open Simplicity Studio and click the Refresh detected hardware button on the left Once the kit appears click on the kit 3 Click the Application Notes tile 4 Search for AN0009 and click the document in the list then click the Import Project button 5 Select the lt kit_name gt _1_registers slsproj option in the dialog and click OK 6 Double click on the 1_registers c file to open it in the editor view There s a marker where custom code should be added For IAR 1 Open up the e
12. R1 reg cal Ox2da 0x6028 STR RO R5 reg volatile uint32_t 0x400C8044UL Ox2dce Ox49le LDR N Ris PC 0 E fv de NNNNA Mavs ps p1 File silabs com Smart Connected E Figure 3 2 Debug View in IAR Warlal arel ha Errors 0 Warnings 0 NUM ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Example 2a Blinking LEDs with an STK 4 Example 2a Blinking LEDs with an STK Since accessing the LEDs is done differently for the Development Kits and the Starter Kits this example is split into two parts 2a for STK and 2b for DK In this example for the STKs the aim is to use the GPIO pins to light up the LEDs on the STK and change the LED configuration every time a button is pressed Instead of accessing the registers directly use the emlib functions to configure the peripherals The starting The AN0009 application note includes a lt kit_name gt _2_leds example in Simplicity Studio and the IAR efm32 workspace contains a project called lt kit_name gt _2_leds which will be used in this example The emlib C files are included in the project The cor responding header files are included at the beginning of the C files For details on which emlib functions exist and how to use them open the API documentation through through Simplicity Studio using the Software Documentation tile or by going to http devtools silabs com dl documentation doxygen After cli
13. SILICON LABS ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones This application note introduces the software examples libraries KEY POINTS documentation and software tools available for EFM32 EZR32 and EFM32 Gemstones e Simplicity Studio contains everything needed to develop with EFM32 EZR32 In addition to providing a basic introduction to the tools available for these devices this and EFM32 Gemstones document includes several basic firmware exercises to familiarize the reader with the Things you will learn Starter Kit and Development Kit hardware the emlib firmware library and the Simplicity Basic register operation Studio software tools Using emlib functions Note that this document focuses on the MCU portion of the devices For wireless prod Blinking LEDs and reading buttons ucts EZR32 see the additional wireless getting started information available in the LCD controller user guide specifically for the product More information on the hardware for any prod Energy Modes uct can be found in the kit user guide More information about Simplicity Studio in gen eral can be found in AN0822 Simplicity Studio User Guide Application notes can be found on the Silicon Labs website www silabs com 32bit appnotes or using the Application Notes tile in Simplicity Studio Real Time Counter operation gt Debug STKXXXblink sre blink c Simplicity Studio leloak Fie Edt Source Refacto
14. TFT display on the main board and also on a PC using the Energy Profiler available in Simplicity Studio 8 2 Advanced Energy Monitor with STK The Starter Kits includes current measurement of the VMCU power domain which is used to power the device and the LCD display in addition to other components in the application part of the starter kit The real time current measurement can be monitored on a PC using the Energy Profiler available in Simplicity Studio 8 3 Step 1 Enter EM1 To enter EM1 execute a Wait For Interrupt instruction An intrinsic function for this part of CMSIS is shown below WFI After executing this instruction observe that the current consumption drops 8 4 Step 2 Enter EM2 Entering EM2 is also done by executing the WFl instruction except with the SLEEPDEEP bit in the SCB_SCR register also set and with a low frequency oscillator enabled To enter EM2 first enable a low frequency oscillator either LFRCO or LFXO before going to deep sleep In this example enable the LFRCO and wait for it to stabilize by using the following emlib function void CMU_OscillatorEnable CMU_Osc_Typedef osc bool enable bool wait Now enter EM2 by setting SLEEPDEEP and executing the WFl instruction SCB gt SCR SCB_SCR_SLEEPDEEP_Msk WEI In addition the EMU emlib functions include functions for entering Energy Modes which firmware can use instead of setting the SLEEPDEEP bit and executing the WFl instruction
15. ble eA Profiler trace O O ORAON BSP_TraceProfilerSetup Delay uint32 y void main void int Setup SysTick Timer for 1 msec interrupts RE ee Silt EE E E console 3 N Tasks J Memory i Problems Executabies x Ee G8 t Bry Program Output Console 0 Em2 Gecko Starter Kit board 123456 USB v Figure 3 1 Debug View in Simplicity Studio For IAR make sure the lt kit_name gt _1_register project is active by pressing the corresponding tab at the bottom of the Workspace win dow Then press the Download amp Debug button and go to View gt Register and find the STATUS register in TIMERO After expanding the register notice that the RUNNING bit is set to 0 Place the cursor in front of the line where firmware starts the timer and press Run to Cursor Then watch the RUNNING bit get set to 1 in the Register View when clicking the Single Step button to move over the expression Continue to click the Single Step button to see the content of the CNT registers increasing Try writing a different value to the CNT register by entering it directly in the Register View silabs com Smart Connected Energy friendly Rev 1 19 8 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Example 1 Register Operation Rese ep O depug Bie oad and Depug IAR forkbench IDE Edit View Debug Disassembly Tools Window Help a fY SAEED HEP s Debus EC
16. bs device Supported devices include the EFM32 EZR32 and EFM32 Gemstones kit either Starter or Development Before working on this tutorial ensure a compatible IDE is availa ble by either e installing Simplicity Studio from Silabs com http Awww silabs com simplicity or if IAR is preferred install the latest Segger J Link drivers to support the kit https www segger com jlink software html In Simplicity Studio ensure that all the available packages are installed and up to date by clicking on the Update Software button at the top right of the main window Note While Simplicity Studio includes a fully functional integrated IDE it also supports some third party IDEs including IAR For this reason it is recommended to install Simplicity Studio regardless of the preferred IDE for easy access to these examples as well as the full suite of features provided to facilitate development of EFM32 EZR32 and EFM32 Gemstones solutions 1 2 How to Use this Application Note The source code for this application note is placed in individual folders named after the kit for which each example is intended The easiest way to access the example source code and projects is through the Application Notes tile in Simplicity Studio Simply click this tile to open the Application Notes dialog SWO Terminal energyAware Battery Software and Kits Software Software Application Kit Documentation Examples Notes Documentation v Part
17. cking on the emlib link for the correct device series Gecko Tiny Gecko etc open up Modules gt EM_Library and select the CMU peripheral Find a list of functions for this peripheral by scrolling down to the Functions section These functions can be used to to easily operate the Clock Management Unit EFIN 32 Functions a Labs EFM32 emlib CMU_ClockEnable CMU_Clock_TypeDef clock bool enable eripheral Library Enable disable a clock 5 u CMU_ClockFreqGet CMU_Clock_TypeDef clock QA EM_Library Get clock frequency for a clock point H ACMP CMU_ClockDivGet CMU_Clock_TypeDef clock 2 apc Get clock divisor prescaler aes BITBAND Get currently selected reference clock used for a clock branch i CHIP CMU_ClockDivSet CMU_Clock_TypeDef clock CMU_CIkDiv_TypeDef div a cmu Set clock divisor prescaler COMMON CMU_ClockSelectSet CMU_Clock_TypeDef clock CMU_Select_TypeDef ref pac Select reference clock oscillator used for a clock branch H DMA CMU_HFRCOBandGet void Get HFRCO band in use H EBI H Emu CMU_HFRCOBandSet CMU_HFRCOBand_TypeDef band Set HFRCO band and the tuning value based on the value in the calibration table made during H GPIO production S 12c CMU_HFRCOStartupDelaySet uint32_t dela INT Set the HFRCO startup delay Figure 4 1 Documentation for th
18. e CMU specific emlib Functions silabs com Smart Connected Energy friendly Rev 1 19 10 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Example 2a Blinking LEDs with an STK 4 1 Step 1 Turn on GPIO clock In the list of CMU functions we find the following function to turn on the clock to the GPIO void CMU_ClockEnable CMU_Clock_TypeDef clock bool enable If we click on the function we are shown a description of how to use the function Clicking on the CMU_Clock_TypeDef link goes to a list of the allowed enumerators for the clock argument To turn on the GPIO add the following CMU_ClockEnable cmuClock_GPIO true Search Q7 void CMU_ClockEnable CMU_Clock_TypeDef clock EFIN 32 bool enable Silicon Labs EFM32 emlib Peripheral Library i Enable disable a clock F Modules S EM_Library In general module clocking is disabled after a reset If a module clock is disabled the registers of that module H AcMP are not accessible and reading from such registers may return undefined values Writing to registers of clock disabled modules have no effect One should normally avoid accessing module registers of a module with a ADC disabled clock AEs H BITBAND nores PETE KAERA E If enabling disabling a LF clock synchronization into the lo
19. e the inter rupt is never deasserted Look for the RTC emlib function to clear the interrupt flag 8 7 Extra Task Segment LCD Controller in EM2 As an extra task enable the LCD controller assuming there s a Segment LCD on the kit in use and write something on the LCD dis play before going to EM2 Use the segment animation from the previous example in EM2 Note This extra task does not apply to the kits that feature a Memory LCD instead of a segment LCD silabs com Smart Connected Energy friendly Rev 1 19 18 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Summary 9 Summary Congratulations You now know the basics of Energy Friendly Programming including register and GPIO operation use of basic func tions on the DK STK and LCD in addition to handling different Energy Modes in the device and the emlib CMSIS functions The Soft ware Examples tile in Simplicity Studio contains several more examples to explore and additional Application Notes are available us ing the Application Notes tile silabs com Smart Connected Energy friendly Rev 1 19 19 Simplicity Studio One click access to MCU and wireless tools documentation software source code libraries amp more Available for Windows Mac and Linux loT Portfolio SW HW Quality Support and Community www silabs com loT www silabs com simplicity www silabs com quality community silabs com Disclaimer Silicon Laboratories in
20. emory i E em_gox_stk_1_re St 4 DISCLAIMER OF WARRANTY LIMITATION OF REMEDIES Energy Micro AS has no obligation to support this Software Energy Micro AS is providing the Software AS IS with no express or implied varranties of any kind including but not limited to any implied varranties of merchantability or fitness for any particular purpose or warranties against infringement of any proprietary rights of a third party Energy Micro AS vill not be liable for any consequential incidental or special damages or any other relief or for any claim by any third party arising from your use of this Softvare Disassembly ee ee ee a FEEEEEEEREEEESEEEESEEEESSES EERE ESEEEEESEEEEEEEE SESE EEE EEEEES EEE EREEEEEEEESEEE include em device h include em _chip h brief Main function Workspace owce mronser X 4 il Messages Building configuration ern_qpox_stk_1_registers Debug Updating build tree Configuration is up to date T Pte Renee eee eee REE REESE REEL EE EEEEEEE EES EE EEEEIEEEEEEEEEEEEEEEE EERE EERE EE Ox2ca 0x492a LDR N Ri PC 0 Ox2ec Ox000d MOVS R5 RI reg cal Ox2ce 0x6028 STR RO R5 reg volatile uint32_t 0x4000402CUL Ox2d0 04929 LDR N Ri PC 0 Ox2d2 Ox000d MOVS R5 R1 cal volatile uint32_t Ox0FEO81C8UL Ox2d4 04929 LDR N Ri PC 0 Ox2d6 0x6809 LDR R1 R1 Ox2d8 0x0008 MOVS RO
21. eripheral header file define _DAC_CTRL_REFRSEL_SHIFT 20 define _DAC_CTRL_REFRSEL_MASK 0x300000UL define _DAC_CTRL_REFRSEL_DEFAULT 0x00000000UL define _DAC_CTRL_REFRSEL_8CYCLES 0x00000000UL define _DAC_CTRL_REFRSEL_16CYCLES 0x00000001UL define _DAC_CTRL_REFRSEL_32CYCLES 0x00000002UL define _DAC _CTRL_REFRSEL_64CYCLES 0x00000003UL define DAC_CTRL_REFRSEL_DEFAULT _DAC_CTRL_REFRSEL_DEFAULT lt lt 20 define DAC_CTRL_REFRSEL_8CYCLES QDACECTRESREERSELacCYChES lt lt 20 define DAC_CTRL_REFRSEL_16CYCLES QDACECTRESREPRSELAh6CYCEES lt lt 210 define DAC_CTRL_REFRSEL_32CYCLES _DAC_CTRL_REFRSEL_32CYCLES lt lt 20 define DAC_CTRL_REFRSEL_64CYCLES _DAC_CTRL_REFRSEL_64CYCLES lt lt 20 For every register bitfield associated shift mask and default value bit fields are also defined define DAC_CTRL_DIFF Ox1UL lt lt 0 define _DAC_CTRL_DIFF_SHIFT 0 define _DAC_CTRL_DIFF_MASK Ox1UL define _DAC_CTRL_DIFF_DEFAULT 0x00000000UL define DAC_CTRL_DIFF_DEFAULT _DAC_CTRL_DIFF_DEFAULT lt lt 0 silabs com Smart Connected Energy friendly Rev 1 19 5 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Register Operation 2 4 4 Register Access Examples When setting a bit in a control register it is important to make sure firmware does not unintentionally clear other bits in the register To ensure this the mask w
22. fm32 workspace an an0009_efm32_getting_started iar efm32 eww 2 Select the lt kit_name gt _1_register project in IAR EW 3 In the main function in the 1_registers c inside Source Files there s a marker where custom code should be added 3 1 Step 1 Enable Timer Clock In this example we are going to use TIMERO By default the 14 MHz RC oscillator is running but all peripheral clocks are disabled so we must turn on the clock for TIMERO before we use it If we look in the CMU chapter of the reference manual we see that the clock to TIMERO can be switched on by setting the TIMERO bit in the HFPERCLKENO register in the CMU peripheral 3 2 Step 2 Start Timer Starting the Timer is done by writing a 1 to the START bit in the CMD register in TIMERO 3 3 Step 3 Wait for Threshold Create a while loop that waits until the counter is 1000 before proceeding silabs com Smart Connected Energy friendly Rev 1 19 7 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Example 1 Register Operation 3 4 Observation For Simplicity Studio make sure the lt kit_name gt _1_register project is active by clicking the project in the left hand Project view Then press the Debug button to automatically build and download the code to the device Click the Registers view and find the STATUS register in TIMERO After expanding the register notice that the RUNNING bit set to 0 In the code view double click the
23. ile in the Software and Kits grouping of Simplicity Studio main page This documentation is also availa ble on the Silicon Labs website at http devtools silabs com dl documentation doxygen silabs com Smart Connected Energy friendly Rev 1 19 4 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Register Operation 2 4 2 Peripheral Structs In the emlib header files the register defines for each peripheral type are grouped in structs as defined in the example below typedef struct __ TO Gint e CTRL PNE SAES TATUS IO uint32_t CHOCTRL IO uint32_t CHICTRL LORONE ZEC Len E oine SA te ETE O Vines fs Otine sok EPC O uint32_t CHODATA O uint32_t CH1DATA ORINE 7 at COMBDATAY TORENT le CAs BIO Muants Zee eBLASE ROC DAC_TypeDef Recall that a register address consists of a base address for the peripheral instance plus an additional offset The peripheral structs in emlib simplify writing to a register and abstract away these underlying addresses and offsets Hence writing to CHODATA in the DACO peripheral instance can then be done like this DACO gt CHODATA 100 Similarly reading a register can be done like this myVariable DACO gt STATUS 2 4 3 Bit Field Defines Every device has relevant bit fields defined for each peripheral These definitions are found within the efm32xx_xxx h e g efm32tg_da c h files and are automatically included with the appropriate emlib p
24. ith the bit firmware needs to set can be OR ed with the original contents as shown in the example below DACO gt CTRL DACO SCTRL DAC _CTRL_LPFEN A more compact version is DACO gt CTRL DAC_CTRL_LPFEN Clearing a bit is done by ANDing the register with a value with all bits set except for the bit to be cleared DACO gt CTRL DACO gt CTRL amp DAC_CTRL_LPFEN or DACO gt CTRL amp DAC_CTRL_LPFEN When setting a new value to a bit field containing multiple bits a simple OR function will not do since this will risk that the original bit field contents OR ed with the mask will give a wrong result Instead make sure to clear the entire bit field and only the bit field before ORing in the new value DACO gt CTRL DACO gt CTRL amp _DAC_CTRL_REFRSEL_MASK DAC_CTRL_REFRSEL_16CYCLES 2 4 5 Grouped Registers Some registers are grouped together within each peripheral An example of such a group is the registers associated with each GPIO port like the Data Out Register DOUT in the figure below Each GPIO port A B C contains a DOUT register and the description below is common for all of these The x in GPIO_Px_DOUT indicates the port wild card 27 5 4 GPIO_Px_DOUT Port Data Out Register Bit Position ane Slee Sle 8121812 Fe lS el Reset Access Description 31 16 To ensure compatibility with future devices always write bits to 0 More information in 1 2 Conven tions 15 0 D
25. manually void EMU_EnterEM2 bool restore Note When in an active debug session the device will not be allowed to go below EM1 To measure the current consumption in EM2 end the debugging session and reset the device with the reset button on the MCU board STK silabs com Smart Connected Energy friendly Rev 1 19 17 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Example 4 Energy Modes 8 5 Step 3 Enter EM3 To enter EM3 first disable all low frequency oscillators before going to deep sleep which is accomplished by using the same technique as for EM2 Disable the LFRCO originally enabled in Step 2 by using the following emlib function void CMU_OscillatorEnable CMU_Osc_Typedef osc bool disable bool wait Now enter EM3 by setting SLEEPDEEP and executing the WFl instruction SCB gt SCR SCB_SCR_SLEEPDEEP_Msk O In addition the EMU emlib functions include functions for entering Energy Modes which firmware can use instead of disabling LF oscil lators setting the SLEEPDEEP bit and executing the WFl instruction manually void EMU_EnterEM3 bool restore Note When in an active debug session the device will not be allowed to go below EM1 To measure the current consumption in EM3 end the debugging session and reset the device with the reset button on the MCU board STK 8 6 Step 4 Configure the Real Time Counter To wake up from EM2 configure the Real Timer Counter RTC to give an
26. n is needed to be able to see the LEDs changing in real time Using the code from TIMERO in Example 1 to create the following function void Delay uint16_t milliseconds Use the PRESC bitfield in TIMERO_CTRL to reduce the timer clock frequency to a desired value silabs com Smart Connected Energy friendly Rev 1 19 13 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Example 3a Segment LCD Controller 6 Example 3a Segment LCD Controller This example requires either an STK or a DK with a Segment LCD This example will demonstrate how to use the Segment LCD con troller and display information on the LCD display The LCD controller includes an autonomous animation feature which will also be demonstrated The ANO009 application note includes a lt kit_name gt _3_Icd example in Simplicity Studio and the IAR efm32 work space contains a project called lt kit_name gt _3_Icd which will be used in this example 6 1 Step 1 Initialize the LCD controller The LCD controller driver is located in the development kit and starter kit library First run the initialize function found in segment 1lcd h to set up the LCD controller 6 2 Step 2 Write to the LCD display By default all LCD segments are switched off after initialization The LCD controller driver includes several functions to control the dif ferent segment groups on the display A few examples are void SegmentLCD_Number int value void Segmen
27. nction Configure AREGA and AREGB shift direction For the STK3700 also set the ALOC bit to SEG8TO15 LCD_AREGA LCD_AREGB e Write data used for animation to these registers Play around a bit with the configuration of the animated segments and watch the results on the LCD display silabs com Smart Connected Energy friendly Rev 1 19 15 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Example 3b Memory LCD 7 Example 3b Memory LCD This example requires an STK equipped with a Memory LCD e g Happy Gecko Zero Gecko or Pearl Gecko This example shows how to configure the Memory LCD driver and write text on the Memory LCD The software project called lt kit_name gt _3_Icd will be used in this example The Board Support Package for the STK includes a driver for the memory LCD Documentation for this driver is found in the Kit BSP s and Drivers section scroll to the bottom under Software Documentation in Simplicity Studio Search a Main Page Modules Data Structures Files Directories EFINM 32 Board Support Package Display H Modules Drivers He CapSense More B cdc gt Collaboration di for Display D Display ollaboration diagram for Display Defines Data Structures Typedefs DISPLAY_Geometry_t Enumerations 5 5 Display geometry specification More Functions DISPLAY_Device_t DISPLAY_DeviceGet Display device data structure including a
28. r Navigate Search Project Run Window Help e ity i N E E S lzAVeva i i i s S5 a 5 Debug 3N act 7 4 Siicon Labs ARM MCU EFM32G890F128 adapter 123456 USB 0 a I STOOK biinkaxt main at blinkc50 Ox gt i General General Purpose Registers 4 tin AES AES D aioi CTRL Control Register gt att CMD Command Register lt T No details to display for the current selection Te hvegistesce a bike 52 BE Outine 2 eo F oie main void Bwastek int count U stdinth El stdboolh Chip errata em_deviceh CHIP_Init a em chiph Gd bsph Ensure core frequency has been updated y SystemCoreClockUpdate bsp_traceh msTicks volatile uint32 t If first word of user data page is non zero enable eA Profiler trace 3 Sankit BSP_TraceProfilerSetup Delay uint32 2 main void int Setup SysTick Timer for 1 msec interrupts lt E console XN Tass G Memory El Probiems executables Ge bbl ef Brina Program Output Console Q EFM32 Gecko Starter Kit board 122456 USB silabs com Smart Connected Energy friendly Rev 1 19 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Introduction 1 Introduction 1 1 Prerequisites The examples in this application note require access to a supported Silicon La
29. rst to configure either the EBI or the SPI connection void DVK_init void Devices with LCD support will automatically be set up with SPI access while devices without LCD support will use EBI by default The yellow lights to the left of the MCU board on the DK indicate which connection is active Note that the connection to the board controller will occupy the EBI or the USART2 SPI on the device as well as the pin connections for these These resources can not be used for other purposes simultaneously As the DVK functions also take care of all the settings needed for the DK connection like GPIO settings etc no other emlib functions are necessary 5 2 Step 1 Change LED Status when the Joystick is Moved Write a while loop that increases a value every time the joystick is moved and display this value on the LEDs The 16 user LEDs on the DK are configured by the following function void DVK_setLEDs uint16_t leds Look inside dvk h for a function to read the joystick status as well Please note that by default the buttons and joystick on the DK are used to control the menu on the TFT display To use the buttons and joystick with the device press the AEM button The button joystick status is shown in the upper right hand corner of the TFT display 5 3 Extra Task LED Animation Experiment with creating different moving patterns on the LEDs like fading and running LEDs Because the device runs at 14 MHz as default a delay functio
30. s and data values it is recommended to use the defines to ensure portability and readability of the code In order to use these defines projects must include em_device h in the c file This is a common header file for all EFM32 EZR32 and EFM32 Gemstones devices Within this file the header file content for the appropriate device is included in the project builds according to the preprocessor symbols defined for the project To simplify the programming of EFM32 EZR32 and EFM32 Gemstones devices Silicon Labs developed and maintains a complete C function library called emlib that provides efficient clear and robust access to and control of all peripherals and core functions in the device This library resides within the em_xxx c e g em_dac c and em_xxx h files in the em1ib folder In the source files included with this application note the em_chip h is included in each and a call to cHIP_Init exists near the beginning of every main function Like the content of em_device h the actions taken within the cHIP_Init function depends on the specific part in use but will include correcting for known errata and otherwise ensuring consistent behavior across devices For this reason do not run any code in the main function prior to running the cHIP_tnit function 2 4 1 CMSIS Documentation Complete Doxygen documentation for the EFM32 EZR32 and EFM32 Gemstones CMSIS library and emlib is available via the Software Documentation t
31. specification of how the display device behaves DISPLAY_DeviceRegister More DISPLAY_DriverRefresh Defines DISPLAY_Init Data Structures DISPLAY_EMSTATUS OK 0 ee a a ee eae ee Figure 7 1 BSP Documentation for the Display Driver 7 1 Step 1 Configure the Display Driver First initialize the DISPLAY driver with DISPLAY_Init The Board Support Package includes TEXTDISPLAY which is an interface for printing text to a DISPLAY device Use TEXTDISPLAY_Ne w to create a new TEXTDISPLAY interface 7 2 Step 2 Write Text to the Memory LCD TEXTDISPLAY implements basic functions for writing text to the Memory LCD Try TEXTDISPLAY_WriteString and TEXTDISPLAY_W riteChar silabs com Smart Connected Energy friendly Rev 1 19 16 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Example 4 Energy Modes 8 Example 4 Energy Modes This example shows how to enter different Energy Modes EMx and wake up using an RTC interrupt The project called lt kit_name gt _4_energymodes is used in this example 8 1 Advanced Energy Monitor with a DK The Development Kits includes current measurement of the VMCU power domain which is used to power the device and the LCD display on the MCU board The VMCU domain is also available on the prototyping board so other external components in the prototype can be added to the measurements The current measurement can be monitored real time on the
32. tLCD_Write char string void SegmentLCD_Symbol lcdSymbol s int on Experiment with putting custom text numbers or symbols on the display and try to make things move about a bit Use the Delay func tion from Example 2 A Delay function can also be found in the solution file silabs com Smart Connected Energy friendly Rev 1 19 14 ANO009 Getting Started with EFM32 EZR32 and EFM32 Gemstones Example 3a Segment LCD Controller 6 3 Step 3 Animate Segments Barrel shift right left _ AREGA7 lt lt AREGA6 lt gt AREGAO E AREGB7 AREGB6 ALOGSEL Barrel shift right left Figure 6 1 Animation Function The LCD controller contains an animation feature which can animate up to 8 segments 8 segment ring on the LCD display autono mously The data displayed in the animated segments is a logic function AND or OR of two register bits for each segment The two register arrays LCD_AREGA LCD_AREGB can then be set up to be barrelshifted either left or right every time the Frame Counter overflows The Frame Counter can be set up to overflow after a configurable number of frames This is not covered by the LCD driver so firmware has to manipulate the LCD registers by doing direct register writes The following registers must be set up LCD_BACTRL Set Frame Counter Enable bit Configure Frame Counter period by setting the FCTOP field Set Animation Enable bit Select either AND or OR as logic fu
33. tends to provide customers with the latest accurate and in depth documentation of all peripherals and modules available for system and software implementers using or intending to use the Silicon Laboratories products Characterization data available modules and peripherals memory sizes and memory addresses refer to each specific device and Typical parameters provided can and do vary in different applications Application examples described herein are for illustrative purposes only Silicon Laboratories reserves the right to make changes without further notice and limitation to product information specifications and descriptions herein and does not give warranties as to the accuracy or completeness of the included information Silicon Laboratories shall have no liability for the consequences of use of the information supplied herein This document does not imply or express copyright licenses granted hereunder to design or fabricate any integrated circuits The products must not be used within any Life Support System without the specific written consent of Silicon Laboratories A Life Support System is any product or system intended to support or sustain life and or health which if it fails can be reasonably expected to result in significant personal injury or death Silicon Laboratories products are generally not intended for military applications Silicon Laboratories products shall under no circumstances be used in weapons of mass destruction including
34. w frequency domain is required If the same CHIP register is modified before a previous update has completed this function will stall until the previous cmu synchronization has completed Please refer to CMU_FreezeEnable for a suggestion on how to reduce 1 COMMON stalling time in some use cases DAC Parameters H DMA in clock The clock to enable disable Notice that not all defined clock points have separate A EBI enable disable control please refer to CMU overview in reference manual H Emu in enable e true enable specified clock e false disable specified clock GPIO oe finiti li f fil H nt Definition at line 1038 of file em_cmu c B LcD References BITBAND_Peripheral CMU_ClockFreqGet and cmuClock_CORE LETIMER Referenced by DMA_Init LEUART H mpu gt Here is the call graph for this function T msc gt Here is the caller graph for this function H PCNT m ie Figure 4 2 CMU_ClockEnable Function Description 4 2 Step 2 Configure GPIO Pins for LEDs The User Manual for a kit is available in Simplicity Studio using the Kit Documentation tile This document describes the usage of all the pins including the user LED s These LED s are connected as follows on several example kits e EFM32 Gxxx STK 4 LEDs on port C pins 0 3 e EFM32TG STK3300 1 LED on port D pin 7 e EFM32GG STK3700 2 LEDs on port E pins 2 3 e EFM32ZG STK3200 2 LEDs on port C pins 10 11
Download Pdf Manuals
Related Search