TMS320F28035-EP: Configuring ADCINT1 as Internal Trigger for Continuous Conversion (No ISR Required)

//###########################################################################
//
// FILE:   Example_2803xAdc_TempSensorConv.c
//
// TITLE:  ADC Temperature Sensor Conversion example
//
//! \addtogroup f2803x_example_list
//! <h1> ADC Temperature Sensor Conversion (adc_temp_sensor_conv)</h1>
//!
//! This example shows how to convert a raw ADC temperature sensor reading
//! into deg. C and deg. K. Internal temperature is sampled continuously
//! through ADCINA5. The coefficients required to compensate for temperature
//! offset are read from TI OTP.
//!
//! \note
//! THIS EXAMPLE USES VARIABLES STORED IN OTP DURING FACTORY TEST. THESE OTP
//! LOCATIONS ,0x3D7E90 to 0x3D7EA4, MAY NOT BE POPULATED. ENSURE THAT THESE
//! MEMORY LOCATIONS IN TI OTP ARE POPULATED WITH VALUES DIFFERENT FROM
//! 0XFFFF
//!
//! \b Watch \b Variables \n
//!  - temp
//!  - degC
//!  - degK
//
//###########################################################################
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// $Release Date:  $
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//###########################################################################

//
// Included Files
//
#include "DSP28x_Project.h"     // DSP28x Headerfile

//
// Defines
//
#define CONV_WAIT 1L //Micro-seconds to wait for ADC conversion.
                     //Longer than necessary.

//
// Globals
//
int16 temp; //raw temperature sensor reading
int16 degC; //temperature in deg. C
int16 degK; //temperature in deg. K

//
// Main
//
void main(void)
{
    //
    // Step 1. Initialize System Control:
    // PLL, WatchDog, enable Peripheral Clocks
    // This example function is found in the DSP2803x_SysCtrl.c file.
    //
    InitSysCtrl();

    //
    // Step 2. Initialize GPIO:
    // Enable XCLOCKOUT to allow monitoring of oscillator 1
    //
    EALLOW;
    GpioCtrlRegs.GPAMUX2.bit.GPIO18 = 3; //enable XCLOCKOUT through GPIO mux
    SysCtrlRegs.XCLK.bit.XCLKOUTDIV = 2; //XCLOCKOUT = SYSCLK

    //
    // Step 3. Clear all interrupts and initialize PIE vector table:
    // Disable CPU interrupts
    //
    DINT;

    //
    // Initialize PIE control registers to their default state.
    // The default state is all PIE interrupts disabled and flags
    // are cleared.
    // This function is found in the DSP2803x_PieCtrl.c file.
    //
    InitPieCtrl();

    //
    // Disable CPU interrupts and clear all CPU interrupt flags:
    //
    IER = 0x0000;
    IFR = 0x0000;

    //
    // Initialize the PIE vector table with pointers to the shell Interrupt
    // Service Routines (ISR).
    // This will populate the entire table, even if the interrupt
    // is not used in this example.  This is useful for debug purposes.
    // The shell ISR routines are found in DSP2803x_DefaultIsr.c.
    // This function is found in DSP2803x_PieVect.c.
    //
    InitPieVectTable();

    //
    // Step 4. Initialize all the Device Peripherals:
    // Configure and Initialize  the ADC:
    //
    InitAdc();
    AdcOffsetSelfCal();

    EALLOW;
    
    //
    // Connect channel A5 internally to the temperature sensor
    //
    AdcRegs.ADCCTL1.bit.TEMPCONV  = 1;  
    
    AdcRegs.ADCSOC0CTL.bit.CHSEL  = 5;  //Set SOC0 channel select to ADCINA5
    AdcRegs.ADCSOC1CTL.bit.CHSEL  = 5;  //Set SOC1 channel select to ADCINA5

    AdcRegs.ADCINTSOCSEL1.bit.SOC1 = 1; // Trigger SOC1 from ADCINT1
    AdcRegs.INTSEL1N2.bit.INT1CONT = 1;  // Allow ADCINT1 to retrigger continuously without waiting for flag clear
    
    //
    // Set SOC0 acquisition period to 37 ADCCLK
    //
    AdcRegs.ADCSOC0CTL.bit.ACQPS  = 36; 
    
    //
    // Set SOC1 acquisition period to 37 ADCCLK
    //
    AdcRegs.ADCSOC1CTL.bit.ACQPS  = 36; 
    
    AdcRegs.INTSEL1N2.bit.INT1SEL = 1;  //Connect ADCINT1 to EOC1
    AdcRegs.INTSEL1N2.bit.INT1E  =  1;  //Enable ADCINT1

    //
    // Note: two channels have been connected to the temp sensor
    // so that the first sample can be discarded to avoid the
    // ADC first sample issue.  See the device errata.
    //

    //
    // Set the flash OTP wait-states to minimum. This is important
    // for the performance of the temperature conversion function.
    //
    FlashRegs.FOTPWAIT.bit.OTPWAIT = 1;

    //
    // Main program loop - continually sample temperature
    //
    AdcRegs.ADCSOCFRC1.all = 0x03;
    for(;;)
    {
        //
        // Sample the temp sensor
        //

        //
        // Force start of conversion on SOC0 and SOC1
        //
//        AdcRegs.ADCSOCFRC1.all = 0x03;
//
//        //
//        // Wait for end of conversion.
//        //
//        while(AdcRegs.ADCINTFLG.bit.ADCINT1 == 0){}  //Wait for ADCINT1
//        AdcRegs.ADCINTFLGCLR.bit.ADCINT1 = 1;        //Clear ADCINT1

        //
        // Get temp sensor sample result from SOC1
        //
        temp = AdcResult.ADCRESULT1;

        //
        // Convert the raw temperature sensor measurement into temperature
        //
        degC = GetTemperatureC(temp);
        degK = GetTemperatureK(temp);
    }
}

//
// End of File
//