DSP_Assign_1
- 1. Lab 1 EENG 3910: Project V - Digital Signal Processing System Design 9/14/2015 Joseph Chandler University of North Texas College of Engineering Electrical Engineering
- 2. Introduction Lab 1 introducesthe TivaTM C SeriesEK-TM4C123GXL. Code ComposerStudio(CCS) isusedforsoftware supportand boththe hardware and software are productsof TexasInstruments. Results and Discussion Problem 1 The firstproblemisan introductiontoCCS.It explainshow toconfigure the TivaTM CSeriesEK- TM4C123GH6XL. Afterthe hardware parametersare set,a sample programisaddedto the new project for analysis.The buildfunctionisshownandthe debuginterface isshown. Problem 2 #include <stdint.h> Thisline containsthe headerfile for variabledefinitions.The headerfileisalreadydefinedinthe CCS software.Examplesof the valuesare bitsize,precision,andsignedorunsignedintegers. #include <stdbool.h> Thisline containsthe headerfile forBooleandefinitions.The headerfile isalreadydefinedinthe CCS software.The file definitionsare usedforoperations,comparingvariables,andprogramcontrol flow. #include "inc/hw_memmap.h" Thisline containsthe headerfile forthe TivaCSeriesdevice memorymapdefinitions.The headerfile containsmanyof the same definitionsusedfordirectregisteraccess.The headerfilecontainsmacros and definitionstosimplifyprogrammingthe peripheral'sregistersandinterruptcontrol.The definitions are usedbydriverlibrariesandare hiddenfromthe programmer. #include "inc/hw_types.h" Thisline containsthe headerfile forcommontypesandmacros.The headerfile containsmanyof the same definitionsusedfordirectregisteraccess.The valuesare awide varietyof general use for items such as arithmetic,clocktiming,file recognition,anddevicerecognition. #include "driverlib/sysctl.h" Thisline containsthe headerfile forthe SystemControl APIdefinitionsandmacros.The headerfile isin the directory"driverlib"of the CCS software.The driversprovideguidedcontrol of the peripheralsand allowsforquickapplication.Enablingperipheralsisanexampleof thiscontrol. #include "driverlib/gpio.h"
- 3. Thisline containsthe headerfile forGPIOAPIdefinitionsandmacros.The headerfile isinthe directory "driverlib"of the CCSsoftware.The driverprovidesasetof functionstocontrol the inputand output module. int main(void){ The main processcalls andacts on variables,macros,definitions,andothersystemfunctions. uint8_t pin_data=2; An unsigned 8-bitintegervariable isinitializedto2 uint32_t delay_count=2.66e7; An unsigned 32-bitvariable isinitialized to2.66e7 SysCtlClockSet(SYSCTL_SYSDIV_5|SYSCTL_USE_PLL|SYSCTL_XTAL_16MHZ|SYSCTL_OSC_MAIN); SystemControl ClockSet setsthe clockingof the device. Osc_Mainconfiguresthe oscillatorsource. XTAL_16MHZ usesa 16 MHZ crystal clock. USE_PLL is a phase lockedloopat 400 MHz. SYSDIV_5divides the clock bythe numberspecifiedgivingcontrol of the frequency SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF); Enablesthe peripheral forthe general purpose input/outputportF GPIOPinTypeGPIOOutput(GPIO_PORTF_BASE, GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3); Thisline configurespinsforuse asGPIOoutputs.The firstparameteristhe base addressof the GPIO port. Inthisapplicationthatwouldbe portF. The nextparameteristhe bit-packedrepresentationof the pins. Thisfunctionprovidesproperconfigurationof the pinswithoutprogramming registers.Type of outputwill be the three onboardLEDs that use portF. while(1) { The while loopprovidesa continuousloop whensetto"1". GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3, pin_data); Thisline writesavalue tothe specifiedpins. The valueiscontainedinthe variable"pin_data".The initial state of "pin-data"is2. Therefore,the value2is giventoall of the pins.Yet,onlyone of the pinswill correspondtothe givenvalue due toa pre-setconditionof 2mA,4mA,and 8mA. SysCtlDelay(delay_count); Thisline providesadelay.The variable "delay_count"holdsthe value of the delayloop. The constantis 2.66e7. The loopiterates3 times. GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3, 0);
- 4. Thisline writes avalue tothe specifiedpins. Therefore,the value0is giventoall of the pins. This essentiallyclearsthe LEDsof all "high"input.NoLED action. SysCtlDelay(delay_count); Thisline providesadelay.The variable "delay_count"holdsthe value of the delayloop.The constantis 2.66e7. The loopiterates3 times. if(pin_data == 8) The "if"statementischeckingif the current value of the pinvariable isequal to8. pin_data = 2; The value of the pinvariable issetto2. else The "else"statementisusedwhenthe currentvalue of the pinvariable isnotequal to8. pin_data = pin_data*2; The value of the pinvariable ismultipliedby2. Problem 3 The EK-TM4C123GXL LED clock rates are increasedwhenthe numberof systemdivisionsare decreased. SysCtlClockSet(SYSCTL_SYSDIV_10|SYSCTL_USE_PLL|SYSCTL_XTAL_16MHZ|SYSCTL_OSC_MAIN); 20 MHz SysCtlClockSet(SYSCTL_SYSDIV_5|SYSCTL_USE_PLL|SYSCTL_XTAL_16MHZ|SYSCTL_OSC_MAIN); 40 MHz SysCtlClockSet(SYSCTL_SYSDIV_4|SYSCTL_USE_PLL|SYSCTL_XTAL_16MHZ|SYSCTL_OSC_MAIN); 50 MHz SysCtlClockSet(SYSCTL_SYSDIV_2_5|SYSCTL_USE_PLL|SYSCTL_XTAL_16MHZ|SYSCTL_OSC_MAIN); 80 MHz Next,the valuesof the variable "delay_count"weredeterminedfor1secondaccordingto the rise in frequency. The desiredfrequencywasdividedby3 cpu cyclesto determinethe time delayinterval neededinthe systemvariable"delay_count". uint32_t delay_count=0.66e7; // For about 1s delay at 20 MHz clock rate. 20MHZ/3 = 0.67e7 uint32_t delay_count=1.33e7; // For about 1s delay at 40 MHz clock rate. 40MHZ/3 = 1.33e7
- 5. uint32_t delay_count=1.66e7; // For about 1s delay at 50 MHz clock rate. 50MHZ/3 = 1.67e7 uint32_t delay_count=2.66e7; // For about 1s delay at 80 MHz clock rate. 80MHZ/3 = 2.67e7 Finally,the variable"delay_count"waschangedtothe resultsabove.The resultof the LED displayis 1 seconddelay. Problem 4 An Introductiontothe TivaC SeriesPlatformof Microcontrollerswasanoverview of TI'snextgeneration of ARM Cortex M4 processors.The reportonthe new microprocessorsboastedof the new 32-bit architecture andhighprecision.The serieshasalarge instructionset andbetterresolutionforcapturing samplesof analogsignalsandconvertingthemtodigital.Multi-taskingandreal-time applicationhas greatlyimproved.Also,the durabilityhasimprovedalongwithlow energyconsumption. TivaWare Peripheral DriverLibraryisa setof driversthatmake the TIVA C Serieseasiertoprogram.They are writteninCfor the most part and efficient.There are multiplesoftwarepackagesthatare available to use all the driversare mappedout fordirectregisteraccess.The driverlibrarycanbe usedalongwith directregisteraccessformore efficientprogramming.The generalpurpose input/outputmodule has8 pinsthat can be configuredasan inputor an outputwithdifferentcapabilities.Also,more thanone pin can be operatedonat one time.The systemcontrol givesmore flexibilitywithabilitiestochange frequency,timing,clock-type,energyuse,andthree differentoperatingmodes. The TM4C123GH6PM MicrocontrollerOverview givesdetailedinformationaboutthe Core, Performance,Flash,SystemSRAM,EEPROM,Internal ROM,Security,CommunicationInterfaces,System Integration,AdvancedMotionControl,AnalogSupport,andhardware layout. The three LEDs are connectedthroughportF of the GPIO module.The schematicshowsthe three LEDs have diodescontrollingthe input.The diodesturnonfor the gatesthat correspondto2, 4, and 8. This referstothe mA that activateseachLED. If itdoesnot containthe right amountof mA the transistoris not activated. Eachiterationof the loopsends a "0" or "off" to all the gatesbefore the new loop iterationiscalculated. Summary and Conclusion The Tiva C SeriesTM4C123G MicrocontrollerwasattachedbyUSB to the CPU and there were notany problemswithpowering onorcompatibilitywithWindows7.CCS wasveryuserfriendlyandoffered differenthardware implementation.The programswere builtwithouterrorandran accordingto plan. CCS programsusedsoftware driverstomapmostof the hardware and applications. References TexasInstruments.(2014).TivaWarePeripheral Driver Library: User'sGuide. Austin,Texas:TI.