tlv_ex3_calibrateTempSensor.c

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//******************************************************************************
//******************************************************************************
 
#include "driverlib.h"
 
uint16_t temp;
volatile float DegF;
volatile float DegC;
float mref, nref;
uint8_t bADCCAL_bytes;
struct s_TLV_ADC_Cal_Data * pADCCAL;
 
//******************************************************************************
//
// This function will initialize and calibrate ADC for temperature sensing.
// The embedded function call of Get_TLV_Info searches the TLV block of data
// (defined in the device header file) for the ADC calibration block, then
// returns the address of the first data descriptor to the pointer passed into
// it. The slope and offset of the corrected temperature curve are then
// calculated for temperature calibration purposes.
//
//******************************************************************************
void calibrateADC(void);
 
void main (void)
{
    //Stop Watchdog Timer
    WDT_A_hold(WDT_A_BASE);
 
    calibrateADC();
 
    while (1)
    {
        //Enable/Start first sampling and conversion cycle
        /*
         * Base address of ADC12 Module
         * Start the conversion into memory buffer 0
         * Use the repeated sequence of channels
         */
        ADC12_B_startConversion(ADC12_B_BASE,
            ADC12_B_MEMORY_0,
            ADC12_B_SINGLECHANNEL);
 
        //LPM0 with interrupts enabled
        __bis_SR_register(LPM4_bits + GIE);
        __no_operation();
 
        //Temperature in Celsius
        DegC = (temp - nref) / mref;
 
        //Temperature in Fahrenheit
        DegF = (9*DegC)/5 + 32;
 
        //SET BREAKPOINT HERE and watch IntDegC and IntDegF
        __no_operation();
    }
}
 
void calibrateADC(void)
{
    //Initialize the ADC12B Module
    /*
    * Base address of ADC12B Module
    * Use internal ADC12B bit as sample/hold signal to start conversion
    * USE MODOSC 5MHZ Digital Oscillator as clock source
    * Use default clock divider/pre-divider of 1
    * Not use internal channel
    */
    ADC12_B_initParam initParam = {0};
    initParam.sampleHoldSignalSourceSelect = ADC12_B_SAMPLEHOLDSOURCE_SC;
    initParam.clockSourceSelect = ADC12_B_CLOCKSOURCE_ADC12OSC;
    initParam.clockSourceDivider = ADC12_B_CLOCKDIVIDER_1;
    initParam.clockSourcePredivider = ADC12_B_CLOCKPREDIVIDER__1;
    initParam.internalChannelMap = ADC12_B_NOINTCH;
    ADC12_B_init(ADC12_B_BASE, &initParam);
 
    //Enable the ADC12B module
    ADC12_B_enable(ADC12_B_BASE);
 
    /*
    * Base address of ADC12B Module
    * For memory buffers 0-7 sample/hold for 64 clock cycles
    * For memory buffers 8-15 sample/hold for 4 clock cycles (default)
    * Disable Multiple Sampling
    */
    ADC12_B_setupSamplingTimer(ADC12_B_BASE,
      ADC12_B_CYCLEHOLD_64_CYCLES,
      ADC12_B_CYCLEHOLD_4_CYCLES,
      ADC12_B_MULTIPLESAMPLESDISABLE);
 
    //Configure Memory Buffer
    /*
    * Base address of the ADC12B Module
    * Configure memory buffer 0
    * Map input Temperature Sensor to memory buffer 0
    * Vref+ = VREF buffered
    * Vref- = AVss
    * Memory buffer 0 is not the end of a sequence
    */
    ADC12_B_configureMemoryParam configureMemoryParam = {0};
    configureMemoryParam.memoryBufferControlIndex = ADC12_B_MEMORY_0;
    configureMemoryParam.inputSourceSelect = ADC12_B_INPUT_TCMAP;
    configureMemoryParam.refVoltageSourceSelect = ADC12_B_VREFPOS_INTBUF_VREFNEG_VSS;
    configureMemoryParam.endOfSequence = ADC12_B_NOTENDOFSEQUENCE;
    configureMemoryParam.windowComparatorSelect = ADC12_B_WINDOW_COMPARATOR_DISABLE;
    configureMemoryParam.differentialModeSelect = ADC12_B_DIFFERENTIAL_MODE_DISABLE;
    ADC12_B_configureMemory(ADC12_B_BASE, &configureMemoryParam);
 
    ADC12_B_clearInterrupt(ADC12_B_BASE,
        0,
        ADC12_B_IFG0
        );
 
    //Enable memory buffer 0 interrupt
    ADC12_B_enableInterrupt(ADC12_B_BASE,
      ADC12_B_IE0,
      0,
      0);
 
    // If ref generator busy, WAIT
    while(REF_A_BUSY == Ref_A_isRefGenBusy(REF_A_BASE));
    // Select internal ref = 1.2V
    Ref_A_setReferenceVoltage(REF_A_BASE, REF_A_VREF1_2V);
    // Internal Reference ON
    Ref_A_enableReferenceVoltage(REF_A_BASE);
    // Wait for reference generator to settle
    while(REF_A_READY != Ref_A_isVariableReferenceVoltageOutputReady(REF_A_BASE));
 
    // TLV access Function Call
    TLV_getInfo(TLV_TAG_ADCCAL,
                0,
                &bADCCAL_bytes,
                (uint16_t **)&pADCCAL
                );
 
    mref = ((float)
            (pADCCAL->adc_ref15_85_temp - pADCCAL->adc_ref15_30_temp))/(85-30);
    nref = pADCCAL->adc_ref15_85_temp - mref*85;
}
 
#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector=ADC12_VECTOR
__interrupt
#elif defined(__GNUC__)
__attribute__((interrupt(ADC12_VECTOR)))
#endif
void ADC12ISR (void)
{
    switch(__even_in_range(ADC12IV,12)) {
        case  0: break;                         // Vector  0:  No interrupt
        case  2: break;                         // Vector  2:  ADC12BMEMx Overflow
        case  4: break;                         // Vector  4:  Conversion time overflow
        case  6: break;                         // Vector  6:  ADC12BHI
        case  8: break;                         // Vector  8:  ADC12BLO
        case 10: break;                         // Vector 10:  ADC12BIN
        case 12:                                // Vector 12:  ADC12BMEM0 Interrupt
            //Move results, IFG is cleared
            temp = ADC12_B_getResults(ADC12_B_BASE, ADC12_B_MEMORY_0);
 
            //Exit active CPU
            __bic_SR_register_on_exit(LPM4_bits);
            break;
        case 14: break;                         // Vector 14:  ADC12BMEM1
        case 16: break;                         // Vector 16:  ADC12BMEM2
        case 18: break;                         // Vector 18:  ADC12BMEM3
        case 20: break;                         // Vector 20:  ADC12BMEM4
        case 22: break;                         // Vector 22:  ADC12BMEM5
        case 24: break;                         // Vector 24:  ADC12BMEM6
        case 26: break;                         // Vector 26:  ADC12BMEM7
        case 28: break;                         // Vector 28:  ADC12BMEM8
        case 30: break;                         // Vector 30:  ADC12BMEM9
        case 32: break;                         // Vector 32:  ADC12BMEM10
        case 34: break;                         // Vector 34:  ADC12BMEM11
        case 36: break;                         // Vector 36:  ADC12BMEM12
        case 38: break;                         // Vector 38:  ADC12BMEM13
        case 40: break;                         // Vector 40:  ADC12BMEM14
        case 42: break;                         // Vector 42:  ADC12BMEM15
        case 44: break;                         // Vector 44:  ADC12BMEM16
        case 46: break;                         // Vector 46:  ADC12BMEM17
        case 48: break;                         // Vector 48:  ADC12BMEM18
        case 50: break;                         // Vector 50:  ADC12BMEM19
        case 52: break;                         // Vector 52:  ADC12BMEM20
        case 54: break;                         // Vector 54:  ADC12BMEM21
        case 56: break;                         // Vector 56:  ADC12BMEM22
        case 58: break;                         // Vector 58:  ADC12BMEM23
        case 60: break;                         // Vector 60:  ADC12BMEM24
        case 62: break;                         // Vector 62:  ADC12BMEM25
        case 64: break;                         // Vector 64:  ADC12BMEM26
        case 66: break;                         // Vector 66:  ADC12BMEM27
        case 68: break;                         // Vector 68:  ADC12BMEM28
        case 70: break;                         // Vector 70:  ADC12BMEM29
        case 72: break;                         // Vector 72:  ADC12BMEM30
        case 74: break;                         // Vector 74:  ADC12BMEM31
        case 76: break;                         // Vector 76:  ADC12BRDY
        default: break;
    }
}