final paper - Union College
Contents
1. A A A tha ena ist 05 Background Hi e ara tare te 07 Design Requirements ii A tail 10 Designaltenatives id 13 Final Design and Implementation caascssssssssssssssssssecsessecsecsecescecesessaessesassescaeceeseesueesaesasesassaesaescaeass 15 Performance Estimates and Results occcncccccnnocaconanannnoncnnanononnnnnnonarnnn anno nnnn anar raro rra rar arras 22 Production Schedule ci AI 26 COSTANA YSIS A A A TA 27 User s Maritial dare aaa 29 Discussion Conclusions and Recommendations ccceesecescesesecseceseseseecseseeseseaeccsecsusesesceeseseeseaseaeeesees 30 Refere n es CA A A a Aita 33 Appendics ai das 34 Introduction For this capstone project have designed an emergency alert system EAS for Union s on campus television station TVuC and radio station WRUC This allows members of Union College s Campus Safety department to activate the system from computers with the client software pre installed select a pre recorded emergency scenario from a list and remotely take over both the TV and radio stations by displaying this emergency information to the campus This system will help the college get pertinent information out to the campus as part of their ongoing reevaluation of the campus wide emergency plan also consisting of SMS based text messaging to those who have opted in campus wide emails and updates to the college s home Web page As the president and technical director of TVuC the campus s te2. It will not be my responsibility to come up with the scenarios as what a student thinks might be an emergency may not in fact call for such alarm and vice versa In addition it will not be up to me to activate the system for the same reasons If did it may cause for a false alarm and get people confused causing chaos In addition if the system is activated but the user selects the wrong message the same can occur The last thing would want is to alert the campus to a building fire when a mass shooter is present in a different location Therefore the system needs to be secure enough that it cannot be hacked into or changed by anyone other than those authorized by college officials Finally there are economic and manufacturability concerns that must be addressed There are currently commercial products available on the market that can accomplish this same task albeit individually for both TV and radio However their implementation is much more complex and the cost is much higher than what the college wishes to implement The cost for this project is very minimal The software used in this project is going to be designed in house so there is no cost associated with that In addition there are already audio links between the radio and TV stations so there is no cost there The main expenditure of the project is in the computer and switches which will control the system The requirements for the computer are quite basic any syste
3. 1 void main void initialize for printf CLEAR SIGNAL RECEIVED n TVUC_OUT 0 disable emergency system for TV WRUC_OUT 0 disable emergency system for radio LED 0 chrs_read scanf s in buf scan for data while in buf 0 a printf EMERGENCY SIGNAL RECEIVED n TVUC_OUT 1 enable emergency system for TV WRUC_OUT 1 enable emergency system for radio LED Ls chrs_ read scanf s in configuration subroutines begin initialization subroutines void initialize void buf scan for data TVUC_GND 0 enable ground for TV WRUC_GND 0 enable ground for radio WDTCN Oxde disable watchdog timer WDTCN Oxad config load configurations UARTO_Init initialize UARTO SYSCLK Init initialize oscillaor printf n n printf AninWelcome to the Union College SYSTEM RESET and Active DO Emergency Alert System for TVuC and WRUC n n configured using Silicon Industries Configuration Wizard void config void configure the XBRn Registers XBRO 0x04 XBARO Initial Reset Value XBR1 0x00 XBAR1 Initial Reset Value XBR2 0x44 XBAR2 Initial Reset Value port configuration 1 Push Pull Output POMDOUT 0x05 output configuration for PO P1MDOUT 0x40 output configuration for Pl P2MDOUT OxOF output configuration for P2 P3MDOUT 0x00 output configuration
4. DDR2 memory 120gb SATA hard drive DVD RW drive The system connects to the TVuC main rack which already included a KVM switch allowing the computer to connect with the already existing monitor keyboard and mouse o 35 Video Card Hardware Switches The hardware switches for the EAS system were custom designed to work with our emergency computer The switches connect various RCA jacks and interface them with an IC that controls what inputs get sent to the output jacks based on the status of an 8051 microcontroller This allows for the video to be forced from normal broadcasting to emergency broadcasting Two of each component was needed as two identical switches were built one for TV and the other for radio 20 Project Enclosures 5 RCA Jacks o 0 Various Resistors diodes wiring and transistors provided by the Electrical Engineering department o 0 5V AC DC converter box o 5 IC o 0 8051 microcontroller provided by the Computer Engineering department o 10 Miscellaneous wiring drill bits and other minor components Backup Hardware Controller At the beginning of this project before any of the current implementation was set in stone we obtained a Mini T NX audio video controller unit The function of this device is twofold Firstly it is used to replace the TV stations former controller which is used to interface all the video inputs with the single a v modulator The new one can be remotely controlled over a T
5. Overview TCP Connection Emergency Override Emergency Computer To SW Interface serial 8051 Microcontroller Input A 1 Emergency VOLTAGE OUT A V Switch Enables Input B Input A 2 N a 5 2 a a 5 3 la o Each switch is connected to a 5V power supply This power supply runs the LEDs as well as an IC which controls the inputs and outputs as well as a relay to switch the inputs from one to another The IC is a CBT3244A which can function for many purposes In the case of the switch the IC is used to send either Input A or Input B out to the output switch based on which enable is selected on the IC Both enables are active low so when the voltage drops the input is enabled Output A and B are crossed and send signal to the same set of output jacks since in this specific usage only one input will 19 ever be enabled at a given time even though for other purposes they both could be Figure 03 below shows the set up of the IC bus switch Figure 03 Diagram of CBT3244A IC Notch circle indicates Pin 1 Input A 1 Output B 4 Input A 2 Output B 3 Output A 1 Input B 4 Output A 2 Input B 3 Output A 3 Input B 2 Output B 1 9 Output A 4 Input B 1 Output B 2 HILIMS SNA VWyb2 1959 Each switch contains a single pull double throw SPDT relay The relay connects each input to the output When the relay is in its default unpowered state Input A is passed to the output port
6. actual presentation given e Week 7 8 Project research e Week 9 10 Additional work on project paper and changes made to preliminary design Winter Break e Web site e Research for hardware to build switch with e Research to allow 8051 to communicate with switch e Build Linux PC which will act as the user interface launch and display the video on the television and provide audio to both TV and radio Winter 2008 e Week 1 Connected TVuC with WRUC hardware implementation and changes at TVuC offices e Week 2 Final research e Week 3 Writing of IEF grant proposal to receive funding for equipment e Week 4 7 Building of switches for TVuC assisting in software development e Week 8 Obtaining measurements preparing presentation presentation e Week 9 Preparing MPEG design additional measurements e Week 10 User manual final paper final updates to Web site 26 Cost Analysis The costs for this project are broken down into the following categories with descriptions and approximate costs detailed Emergency Computer A computer must be dedicated to this project as it will be needed to control the hardware switches and produce the emergency messages The machine was donated by the TV studio with the only upgrade needed was a video card that had a TV out connection The machine runs Ubuntu a build of the Linux operating system chosen for its virtual 100 uptime Other specifications include a Intel Celeron D processor 1gb
7. familiar with its operation so a brief skim through of the User s Manual is recommended In addition it is recommended that Campus Safety have enough users trained to launch the system so that someone is always available to do it Future improvements as always can be made to this project The first would be the implementation of better hardware switches see Figure 10 below Take the same physical hardware requirements and package it into a printed circuit board This decreases latency among the switching and improves reliability as the internal connections will be more stable In addition a GUI for the 30 software will make user operation clearer Finally a long term improvement would be to modify this implementation such that a user could enter a custom message which would then be placed on the screen and read via text to speech However with any of these improvements the system will still accomplish the same goal alerting the campus to an emergency Figure 10 Internal Hardware Switch Wiring Implementing this project has been a great educational endeavor for myself Overall had to listen to a client who knew nothing about the technical implementation or limitations of a system and design a system that took all their requirements and satisfied them Then had to figure out how to correctly wire up the hardware switches This included soldering 16 wires to a surface mount IC without getting any solder to touch adjacent
8. for P3 P740UT 0x00 output configuration for P4 7 P1MDIN OxFF Input configuration for Pl this routine initializes the system clock to use an 22 1184 MHz crystal as its clock source void SYSCLK Init void LE Ts OSCXCN 0x67 for 1 0 i lt 256 i while OSCXCN amp 0x88 OSCICN 0x88 detector configure the UARTO using Timerl delay counter start external oscillator with 22 1184 MHz crystal wait for oscillator to start wait for crystal oscillator to settle select external oscillator as SYSCLK source and enable mission clock for lt baudrate gt and 8 N 1 UART 0 uses PO pin 0 for TX and PO pin 1 for RCV void UARTO_Init void SCONO 0x50 SCONO mode 1 8 bit UART enable RX TMOD 0x20 TMOD Timerl mode 2 8 bit reload TH1 SYSCLK BAUDRATEU0 16 set Time TRI 1 CKCON 0x10 T PCON 0x80 S8 TIO 1 reload value for baudrate start Timerl imerl uses SYSCLK as time base MODOO 1 disable baudrate divde by two Indicate TXO0 ready 35 Appendix B Backup EAS System User s Manual This is an outline Look for the final User s Manual coming soon Launching System Backup Plan 01 Manually launch from TV station Backup Plan 02 Manually launch using TVuC controller User name Safety o Password Campus o IP address tvuc union edu o Procedure Launch Mini T NX software from desktop Login Click
9. the switches that were custom built made this much easier more secure and far less expensive Another alternative would have been using a premade hardware controller In the television studio one already exists to store and launch programming This device can launch various slides and could have been used to implement this project However it would have required a great deal of client training with its proprietary software and still would not have been as clean as the actual system implemented In fact getting it to communicate with the radio station would have required additional 13 hardware which would have added additional costs The controller requires a user to log into its proprietary software pause current programming locate the emergency video file and output it Resetting the controller once the situation is over is just as hard Such a device is quite expensive as well and to dedicate them entirely to an emergency alert system would be cost inefficient That being said have experimented slightly with this and have in fact used this as a temporary solution for Campus Safety to display a simple slide on the television alerting viewers to log onto the college s Web site for more information until the final implementation was completed Only a single member of Campus Safety got trained and still had trouble learning the system Luckily it never needed to be activated in the short time it was in use Another alternative wo
10. 51 is programmed using the C language using configuration modules that were pre created by the development board s Configuration Wizard Configuration was necessary to allow the 8051 to receive commands from its RS 232 port as well as the configuration of PORT O which is used to interface with the hardware Two pins pin O and 2 on PORT O were configured to switch between high and low to control the state of the hardware switch with pins 1 and 3 set low to function as ground ports Pins O and 1 control the switch for the TV station while pins 2 and 3 control the switch for the radio station 16 The logic written to the 8051 does the following upon powering up or resetting the 8051 perform the necessary configuration commands so that the 8051 does what is mentioned above then enter the default ready state In this state the 8051 waits for the character a for activate to be sent over the serial connection If the 8051 receives the character a it then launches the emergency scenario state In this state pins O and 2 are switched high so that a voltage is outputted from the microcontroller to the switches In addition the diagnostic board s LED is lit to show that the 8051 is indeed in the emergency state While in this state it waits for any other character to come over the serial connection in which it will return to the default state which in turn resets the hardware switch Using a simple character to enable
11. CP IP connection anywhere on the Union network which helps the TV studio manage their broadcastings In addition it contains a hard drive and software which can store video and still slides on the device Finally it can create a detailed programming schedule and automatically switch inputs on its own With regards to this project Campus Safety is given a specific login to the software in which they can launch an emergency scenario from there This is designed as an backup alternative plan should the original system go down or become unstable Using this device requires proprietary software preinstalled on the user s system as well as some training to launch the specific scenarios Instructions on operating are located in the user s manual o 2800 Mini T NX provided graciously by the Campus Safety department 27 Software All software including the logic to run the 8051 microcontroller the client software and the server software as well as the MPEG files used to display the emergency messages were custom designed by myself and my project partner SO Ubuntu OS o 0 EAS System for 8051 Microcontroller o SO EAS Client software o SO EAS Server software 28 User s Manual Since this project is not yet complete due to the lack of software arising from my partner s absence the User s Manual is not yet complete However Appendix B contains the User s Manual for the backup EAS system also implemented 29 Discussion Conc
12. For Union College Television and Radio Union Buliding Emergency Y WESTRULEGE Leave area now Go to the a MENA Ulaga otf Campus de not enter campus Walt for additional instructions Sce for information Dave Swift Senior Capstone Project ECE 499 Winter Term 2008 April 9 2008 Advisor Prof James Hedrick Report Summary This report is designed to give the reader an overall yet detailed description my senior capstone design project At Union College all senior Computer Engineering students must complete a project of their own choosing Students work in small teams or on their own and alongside a faculty member on their project The project spans a total of 30 weeks ECE Web site where students design a project and implement it For my particular project have chosen to implement an Emergency Alert System EAS for Union College s television and radio stations TVuC and WRUC respectively This comes on the request from Union s Campus Safety department who had plans regardless of this project to implement such a system This project includes both software and hardware prototypes as both are necessary for the system to function completely This project allows for members of Union Colleges Campus Safety department to activate the system from computers with the client software pre installed select a pre recorded emergency scenario from a list and remotely take over both the TV and radio stations by displayin
13. adapter with TV out 17 and a 160gb hard drive all of which are well above the required specifications but still cost efficient to allow the system to run smoothly without ever over taxing the machine Figure 01 Hardware Switch The real home made hardware lies in the form of the switches which change the broadcasting from normal operations to emergency operations lt made the most sense to build two switches each of which are identical one being housed in the television studio to control the television broadcast and one housed in the radio studio to control the radio broadcast Each switch takes in two inputs input A and B with each input containing two channels channel 1 and channel 2 and outputting either input A or B Figure 02 below shows the basic setup for the IC In the case of the TV switch channel 1 is audio and channel 2 is video while with the radio channel 1 is left audio and channel 2 is right audio In all cases the physical input jacks are RCA This is sufficient since the TV station functions using mono audio only while the radio station does not need any video to be passed Input A the default input 18 connects to the normal broadcasting while Input B connects to the emergency broadcasting Each switch contains a power LED showing when the switch is on no signals will be passed without power as well as a LED for each input to show which input is currently active Figure 02 Emergency System
14. are RCA audio and video and passes the output to both our video modulator which converts the A V signals and broadcasts them over our CATV network and a monitor for sampling before broadcasts go live In our case we have multiple DVD players a VCR and a computer all hooked up to this controller and both audio and video from these devices pass through the controller However what makes this controller special is the fact that not only can it control these devices it also contains an internal hard drive which can store MPEGs and JPEGs and can be accessed anywhere on campus over a TCP IP connection so long as the proprietary software is preinstalled This means that we can store the emergency scenario slides on this device in which Campus Safety could use should the new system fail One may wonder why this other system is necessary The simple answer to this is its software is quite cumbersome and unintuitive and would be nearly impossible to use by an untrained user In addition only a user with administrative rights can update the device should other scenarios need to be added Thus it will function as a backup system going forward which was deemed necessary by my client Design Requirements To fully understand the requirements for this system specifics for television and radio have to be recognized as all audio and or video for both TV and radio will be passing through the EAS For the entire system to work it is assumed and requir
15. cy switches which then forces the output on both ends to the audio and or video coming from the emergency computer The process is repeated when the scenario is over with the user selecting the clear system message which ends the MPEG display and resets both hardware switches to the default state resuming original programming The software that will operate this project is broken down into four aspects including the client software the server software the scripts to launch the MPEG files and the software which runs the logic of the 8051 microcontroller As mentioned earlier the implementation of the client software was done in Java to allow the most compatibility across different platforms that may be used With Java if the client is using Windows Mac or Linux hardware the same build of the software will work across all platforms Upon launching the software the client is presented with a prompt asking for their user name and password and once authenticated the client software will request from the server a list of all available MPEG files This was done to allow the client to see newly added scenarios without having to recompile any or all pieces of software The client then selects the scenario they wish to display and a command is sent to the server to perform the remaining operations The only other function of the 15 client software is to send the all clear message to restore the system to the default state This f
16. ed that electricity and internet are available to the television and radio studios located in the Reamer Campus Center on the Union College Campus Obviously without electricity the entire cable and radio systems would be non functional as they are currently set up without backup generators If a reliable connection to the internet were to become unavailable a manual activation can be completed from the emergency server located in the television studio The client software will run alongside the server software so the interface is no different to the user if they were to launch it from this machine which would not require an internet connection If neither option is viable the emergency system will fail to activate a design limitation that is acceptable to my client In addition a physical audio link is required between the emergency computer and the television and radio broadcasting equipment Since both of the studios are adjacent to each other a simple audio out connection from the television station to the radio station has already been established between the two rooms and will be used with the EAS This simplifies the deliverance of the audio from the emergency computer to both media outlets The entire system will be controlled primarily by a dedicated computer running Ubuntu a distribution of the open source Linux operating system Linux has been chosen since it is open source making the cost nothing while reliability is phenomenally h
17. ementation Program Emergency Alert System for TVuC WRUC Union College Author Dave Swift Winter 08 assisted by Prof James Hedrick NOTES LED P1 6 causes UART 0 to stop working UART 0 uses PO pin 0 for TX and pin 1 for RCV UART 1 uses PO pin 2 for TX and pin 3 for RCV PORT P2 is used for DIO with pins 0 3 configured as outputs and pins 4 7 configured as inputs pragma CODE include lt c8051f020 h gt include lt stdio h gt include lt string h gt sfrl6 DP 0x82 data pointer sfrl6 TMR3RL 0x92 Timer3 reload value sfr16 TMR3 0x94 Timer3 counter sfr16 ADCO Oxbe ADCO data sfr16 ADCOGT 0xc4 ADCO greater than window sfr16 ADCOLT 0xc6 ADCO less than window sfrl6 RCAP2 Oxca Timer2 capture reload sfrl6 T2 Oxcc Timer2 sfrl6 RCAP4 0xe4 Timer4 capture reload sfrl6 T4 0xf4 Timer4 sfr16 DACO 0xd2 DACO data define SYSCLK 22118400 SYSCLK frequency in Hz define BAUDRATEUO 9600 Baud rate of UARTO in bps void initialize void void SYSCLK Init void void config void void sync_pulse void void UARTO Init void sbit LED P1 6 LED built in development board sbit TVUC_OUT P2 0 0 normal program 1 emergency sbit WRUC_OUT P2 1 0 normal program 1 emergency sbit TVUC_GND P2 2 used as a ground connection for TV sbit WRUC_GND P2 3 used as a ground connection for RADIO int chrs_read char in buf
18. g this emergency information to the campus This system will help the college get pertinent information out to the campus as part of their ongoing reevaluation of the campus wide emergency plan also consisting of SMS based text messaging to those who have opted in campus wide emails and updates to the college s home Web page As the president and technical director of TVuC the campus s television network was approached with the idea to implement such a design and decided to do this for this particular design project which further shows the real world relationship between a practicing engineer and their client Much of the software portion of this project pertaining to the client server and scripting was designed and written by my former project partner Zach Smith who had become ill halfway through the Winter term and has dropped out from the remainder of the project Therefore the final implementation of the software and details about the aspects of said software are minimal as he was unable to complete the implementation for the project due date Therefore for the remainder of this paper we will assume that the software has been implemented appropriately so that the system fully functions In the future hope that this is actually completed either by him or by a new student so that our client is indeed satisfied with the implementation Table of Contents ReportSummMatry ia 02 Table orContents A A di 04 Introduction
19. he way our client desired it to with ease of use low cost for implementation and security and reliability A sketch of the final circuit design can be seen below in Figure 04 Figure 04 Sketch of Final Circuit Implementation i ok bh a Y A 3 fr gt SS EMAILS A 4 2 Ls J N S EAA SBLE sv IW IS 21 Performance Estimates and Results The way this project was implemented allows for full functionality with the client able to remotely launch the system and take over the television and radio stations with emergency broadcasting The most important variable in this system was making sure that the input levels without passing through the hardware switch match that of the output when going through the switch To make sure this was the case measurements of the attenuation of the switch were obtained As a reference a standard composite video signal which is used in this system has a bandwidth of 4 2MHz while audio has a bandwidth of 44 1 KHz Using an oscilloscope see Figure 05 below and applying various frequencies to the IC in the switch using the function generator could obtain the approximate level when the output over the input becomes less than 1 0 causing peaking among the signals leading to distortion At approximately 9MHz the output input drops to 0 9 and at 12MHz this begins curving downwards quite rapidly Therefore it can be concluded that the attenuation of the switch is normal up un
20. igh Requirements for the computer include the fact that it must be running 24 7 and must not automatically restart perform system updates or do anything else that would interfere with the operation of this system which other operating systems may do In addition Linux works natively with C which is the language the server software has been written in The computer must also be able to activate the hardware switches via a serial out connection to an 8051 microcontroller Finally the computer will serve as a media server containing 10 the necessary files for each scenario presented to the user and output the necessary video and audio when activated through its TV out and audio out connections To simplify the process and reduce the chance of an error occurring it makes the most sense to store the text and video in simple uncompressed MPEG video files For each emergency scenario a separate file exists Each file contains a simple slide of fixed text to display on the screen along with an audio track containing a recording of the message being broadcasted some with additional information that cannot fit on the screen The messages have been provided by Campus Safety The length of the file will be determined based on the length of the audio track and when it ends the entire clip will loop automatically defined by a setting in the MPEG player native to Linux The MPEG video file can also be played natively by Linux so no special softwa
21. levision network was approached with the idea to implement such a design and decided to do this for this particular design project which further shows the real world relationship between a practicing engineer and their client The overall objective of this project is to allow authorized users to easily and quickly get emergency scenario information on the TV and radio should an emergency arise In order to accomplish this switches needed to be built for both the TV and radio components and software needed to be written to control the system The switch for TV forces the audio and video outputs from the default state to the output of a computer containing emergency scenario information The switch for radio does the same but instead of taking in audio and video it simply takes in stereo audio In addition to the switches a computer was dedicated to the project which contains the prerecorded emergency scenarios as well as the server software which will launch the video and activate the hardware switches The emergency scenario information is stored as MPEG video files however the video simply contain a single frame containing written text displaying the message along with an audio clip of the scenario Therefore when the user selects a specific scenario the computer will automatically begin playing the video file as well as transmitting an output command to the necessary hardware switches Thus when the system is active the TV station dis
22. lusions and Recommendations Now that this project is complete have provided my client Union College s Campus Safety department with a method of alerting the campus community to an emergency scenario should one arise on campus With ease a user can log into software on their own machine locally select the scenario that applies to the emergency and activate the system providing views of both the television station and radio station with pertinent information This combined with other emergency notification systems already present improves safety overall on campus The goal of this project was to implement a system that would take over both the television and radio stations from a single remote source with virtually complete uptime low activation time and ease of use so that users who are unfamiliar with the system can launch it This project accomplishes all of these goals The system should not crash or need to be rebooted activates in less than two seconds and is extremely user friendly The trickiest part of the system to the user is remembering their login credentials Once they are logged in they can easily select one of the pre recorded scenarios and hit launch and the system will active In addition a backup plan has been implemented albeit harder to operate However should one system go down the other will still be available for usage For this system to be used to its full advantage does require that the user be somewhat
23. m with sufficient hard drive space which is supported by the Linux platform and has TV out capabilities is sufficient for functioning as the server and is fairly inexpensive The switches that override current broadcasting with emergency information are also inexpensive as the main cost comes from the 8051 microcontroller which will be used to activate the switches when the system is activated The software coding which will run the video clips and activate the system will also be programmed in house so no outside software will really be required to run the system Therefore cost will be as low as possible while the benefits of this project will be quite high Prior to this past fall term when the actual design and implementation of this project came to fruition worked with my client to implement an alternative system which served as a temporary solution and as a backup system should this new system ever fail The alternative system is not nearly as user friendly as my system however it does allow emergency information to be presented to the campus community Campus Safety has purchased upon the recommendation of the TV station a Leightronix Mini T NX Digital Video Server This device functions with two major rolls Not only does it serve as a backup for storing emergency alert information it is our main video head end controller in which all broadcasts for the television station pass through It contains multiple inputs all of which
24. o have opted in campus wide emails and updates to the college s home Web page As the president of the television studio TVUC was approached by the director of Campus Safety Bill Sickenger in the spring of the 2006 2007 academic year with hopes that could implement the television component for them Adding the radio component would only take little more effort than simply the television portion so decided that would indeed be able to implement some form of emergency alert system EAS However due to the complexity of a successfully working system was unable to simply do this in my spare time It then dawned on me that could implement the system for this capstone design requirement as it would not only accomplish the goals and requirements of such as project it would actually have an engineer client component to it Now that the project is complete feel that have been able to assist the college in accomplishing their goal for alerting the campus when a situation occurs There are many aspects of this project that deal directly with society Most importantly this project deals with the health and safety of those on campus as well as the social and ethical impact Since anytime an emergency situation occurs communication among officials must be planned out and well implemented preventing an even worse situation from happening Therefore this project will produce a product which is a tool for dealing with the situation
25. oking at potential design alternatives slight modifications could have been implemented to the actual design or completely different implementations could have been used For example the client software could have been coded in C instead of Java but platform compatibility would have been compromised In addition the client server software could have been Web based yet the security would have been much less even with encryption As far as launching the emergency messages an alternative possibility was to use still slides with separate audio clips However this would have been much more complicated and would have required more programs to be launched when the system is activated Microsoft PowerPoint was considered for doing this with audio implemented in the background of each slide Finally a different type of scripting interface could have been used to launch the system The alternatives and combinations of getting the message out are endless and feel confident that what has been chosen will be the most efficient method of implementation for this system The hardware could have been implemented many different ways some of which depend on the software which is used A pre manufactured switch could have used instead of our custom switches However finding one that interacted with the computer which is a requirement was not only nearly impossible but extremely expensive and required additional proprietary software to control it Using
26. on window at top Etc o When complete return broadcasting to normal scenario Should a problem arise with the hardware switches Should the software not connect make sure that the connection from the client to the server is available by running a ping command towards tvuc union edu To do this click Start gt gt Run and type in cmd and hit OK Then at the C gt prompt enter ping tvuc union edu If the system returns request timed out contact ITS to determine why the connection has gone down If it goes through try restarting your machine If this too fails the system in Reamer in the TV offices must be reset Please contact the president or technical manager of the TV station to do this 36
27. pins In addition had to figure out how to switch inputs from one source to another via an electronic signal This involved familiarizing myself with relays and transistors and implementing a microprocessor and necessary logic to accomplish this Finally and most 31 importantly learned how to verify that no signal degradation was occurring with my hardware needed to make sure that audio and video got passed through the switch without any loss whatsoever Research prior to implementation showed that should not have any loss yet a faulty connection or an improper ground could lead to such conditions However tests using a signal generator and oscilloscope have proven that no loss occurs 32 References and Links Project Home Page David A Swift http antipasto union edu swiftd Reference for Switch implementation Engadget March 13 2007 http www engadget com 2007 03 13 how to make a solid state a v switcher CBT3244A Datasheet AllDataSheet com http www alldatasheet com datasheet pdt pdf 109603 PHILIPS CBT3244A html Composite Video Wikipedia http en wikipedia org wiki Composite video Video Circuits Maxim IC http pdfserv maxim ic com en an AN734 pdf Student Projects Electrical and Computer Engineering Union College htt Digi Key Corporation vendor http www digikey com Newegg vendor http www newegg com ece union edu rojects 33 Appendices Appendix A Code for 8051 Impl
28. plays a slide of text along with audio accompaniment and the radio station simply broadcasts that audio component This way anyone watching the TV station or listening to the radio station will see and or hear the important information during emergency alerts This report is broken down in a way which gives the reader an overall feeling for the project then goes into design specifications and technical specifics Potential alternative implementations are then presented along with reasons why they were not chosen instead Results are then discussed and any additional information relating to the project including the production schedule detailed allotment of costs and references are given In addition a User s Manual is provided which will be presented to Campus Safety for their training purposes and will be referenced by them if they run into trouble launching the system Finally an appendices section is included containing the source code for all software written exclusively for this project Background After the April 16 2007 massacre at Virginia Polytechnic Institute college campuses across the nation have begun to re explore their emergency scenario plans At Union campus officials have decided to implement a better system of notifying students faculty and staff should a situation on our campus arise This includes notification via the college s television and radio stations as well as SMS based text messaging to those wh
29. puter and sends audio to both the television station s modulator and radio station output The television and radio stations broadcast nearly 100 of the time Therefore a system had to be designed that would pass the normal broadcasting through without any loss of signal yet be able to interrupt it when an emergency message needs to be sent through Thus a switch has been designed that will pass the normal broadcasting through unless it is switched via the emergency computer In this case it will output the emergency messages until reset by an authorized user in which normal broadcasting will resume There are two switches used in this project one for television and one for radio Finally Campus Safety has requested that a backup plan be available should some component of this system fail A backup plan has been implemented for the television station which is based on the studio s Leightronix Mini T NX Digital Video Server which functions as the main controller for all of the station s video sources Since this device can be accessed via a TCP IP connection and contains an internal hard drive which can store MPEGs and JPEGs emergency scenario slides can be stored on this device in which Campus Safety could use should the new system fail Since the software quite cumbersome and unintuitive and would be nearly impossible to use by an untrained user it will function solely as a backup system 12 Design Alternatives When lo
30. re will be required for this operation to run Based on the requests of my client the finished product must easily be accessible if and when it needs to be activated Upon reviewing possible implementations to accomplish this such as using proprietary software and or hardware it made the most sense to have unique software installed on the client side to activate the system This client software is coded in Java so cross platform compatibility is the greatest Therefore the system can only be launched on systems that Campus Safety deemed acceptable The software has a hard coded IP address and port mapping to the server and will NOT be accessible outside the campus This is done to prevent people who have obtained the software from otherwise hacking the system and launching it when it is not appropriate In addition the server will require user authentication in the form of a user name and one complex password Upon logging in the user will be presented with all scenarios available in a simple text or button interface as well as a reset interface to resume normal programming once the emergency is over This is done for simplistic purposes and to allow new messages to be displayed without having to recompile and rebuild the software each time Each scenario references the corresponding video file and passes this information 11 via a script into the media player which launches the correct video slide in full screen on the TV out port of the com
31. rther research was spent analyzing the results of composite video passing through the oscilloscope Figure 07 below shows the waveform captured using the switch while Figure 08 shows the waveform captured without using the switch This too shows that the switch is indeed passing a correct composite video signal Figure 08 shows a standard composite video waveform Figure 07 Waveform Captured w o Switch gilent Technologies 24 Figure 08 Waveform Captured w Switch Agilent Technologies Figure 09 Composite Video Waveform 28 LSB U IRE 10 BRIGHT 41 073 PEAK VIDEO 1 0004 REFERSNCE WH TEI 256 LSB 92 5 IRE Wy 3 1399 Y REFERENCE BLACK 3 285 V REFERENCE BLANK 21 L53 1 5 IRE 7285 Y 170 LSB 40 IRE 0 000 Y SYNG LEYEL 25 Production Schedule Pre Fall 2007 e Work with Campus Safety to establish design of system e Research methods of implementation suitable to client s request and for senior project requirements e Prepare TV and radio equipment for implementation of EAS Fall 2007 e Week 1 2 Set up new TV studio includes necessary internal wiring configuration of computers and equipment This will prepare us for our new interconnections with TVuC and WRUC e Week 3 4 Writing of IEF grant proposal to receive funding for equipment e Week 5 Draft of presentation for project presentation e Week 6 Dress rehearsal of presentation and
32. s but when a voltage of 5V is applied to the relay it switches to passing Input B effectively disabling Input A The relays are connected to the 5V power source inside the switch with the ground connection running to the 8051 microcontroller When the microcontroller is put into the emergency state the relay s coil is closed circuited allowing the relay to switch from Input A to Input B Finally a diode was installed across the relay s coil as a precautionary measure to prevent a spike in current flowing the wrong way which would burn out the coil One obstacle had to overcome was the fact that the voltage outputting from the 8051 is 3 3V while the relay requires 5V to operate This was accomplished by adding a 2N3904 transistor to the switch and connecting the ground connection from the relay to the collector connecting the 8051 to 20 the base and connecting the emitter to the switch s ground connection This allows the relay to obtain the 5V from the switch s power supply and obtain a ground connection when the 8051 is activated therefore completing the circuit and switching the relay With everything correctly implemented the client can indeed select the appropriate scenario which forces the server to launch the corresponding MPEG slide activate the 8051 microcontroller which changes each switch from Input A to Input B When all is done the system can correctly be reset Therefore this system functions exactly t
33. the switches was chosen such that the server can send multiple activation commands without flip flopping between ready and emergency just to make sure that the command went through successfully So if the 8051 receives five activation commands it is the same as a single command The same applies to the clear command The code used to implement this logic in the 8051 can be seen in the appendices The hardware implementation involves two aspects the emergency computer and the emergency switches see Figure 01 below The design implemented calls for a computer to function as the emergency server containing the server software the MPEG launch scripts and the MPEG files For the system to be as stable as possible and have the most uptime Ubuntu a build of the Linux operating system was chosen which provides a much higher uptime compared to Windows and to an extent Mac OSX With Windows the system may lockup do an automatic update or display a reminder pop up all of which could interfere with the display of the MPEG slides Since the computer must run virtually unattended Linux will do exactly what is desired The special requirements for the computer include a hard drive large enough to store each MPEG file each of which is only a few megabytes and has TV and audio out capabilities These requirements are not that great so chose to build a new system with a Celeron D based processor a gigabyte of memory a PCl express based graphics
34. til at least 9MHz Since a max of 4 2MHz is being sent for video and 44 1KHz for audio which is less than half the bandwidth then the max supported by the IC it can safely be said that there will be absolutely no distortion among signals passed through the switch Figure 06 below shows the attenuation of the IC 22 Figure 05 Testing Environment NY Y gt Figure 06 Graph of Frequency Response of Switch Frequency Response of Switch gt Qa gt Q gt O 10 Frequence MHz 23 In addition to the output levels the entire system must activate 100 of the time and within a matter of seconds as delay in an emergency situation can lead to more problems and added chaos Upon testing just the hardware portion the time it takes for the computer to send the activation command to the 8051 which switches the inputs is approximately 0 1 seconds and appears nearly instantaneously to the eye The computer takes approximately two seconds to launch the MPEG file once it receives the command from the client to launch the script That being said am unable to give a reading for the time it takes to launch the software as its development is not quite complete at this time However the time it takes from the time the client hits the activate button on their end to the time the emergency scenario is approximately 2 3 seconds which is well within the range specified by the client Fu
35. uld be to purchase two separate emergency alert systems designed specifically for television or radio This would accomplish the goals of the project however the cost in doing this would be ridiculously high Many implementations for television require cable company approval or implementation which would be out of our reach Finally certain mandates that may not necessarily apply to a campus like ours may be implemented by governing bodies such as the FCC again boosting the complexity and overall cost Those provided by the cable company may require a monthly fee which can easily be avoided with my system 14 Final Design and Implementation The final implementation of this project includes custom designed software and hardware which make an emergency alert system When correctly implemented the system allows a user from Union College s Campus Safety department who is authorized by them to launch client software pre installed on their computer systems to log into the system select a pre recorded emergency scenario also determined by them which then sends a command to the emergency computer which launches the appropriate message s MPEG file which outputs the video of the message over the computer s TV out controller and audio through the computer s sound card In addition the computer sends an activation command to the system s 8051 microcontroller which flips the inputs in both the TV station and radio station s respective emergen
36. unctions just like any other scenario on the client side The server software is fairly simple as well The server waits in an always ready state looking for the activation command from the client Once a command is received the server then launches the appropriate script to actually launch the MPEG file on the secondary display of the computer which is connected to the TV out and in turn displays the message on the TV In addition the server software sends an emergency scenario activation command over the computer s serial port which is connected to the 8051 microcontroller Once both the MPEG is launched and the 8051 enable command is set the server software returns to the ready state waiting for another command be it another emergency message or a clear all If the special clear all message is selected the server software launches a script to close out the MPEG file and resets the 8051 to its default ready state The scripting functions are built into the server software The same script is used for all scenarios except the clear all and the file name is plugged dynamically into the script so that the appropriate message is displayed The clear all script simply closes the media player which ends the broadcasting of the scenario message The last aspect with regards to software is the logic that controls the 8051 microcontroller The software implemented here is also quite straightforward The 80
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