Forums

Hai,

   I am working on TMS320F28335. I need to generate a pulse when the sampled value through ADC is less than a specified value. Following is the piece of code I am trying to use. Kindly help me in getting the proper output.

#include "DSP2833x_Device.h"

extern void InitAdc(void);
extern void InitSysCtrl(void);
extern void InitPieCtrl(void);
extern void InitPieVectTable(void);

void Gpio_select(void);

#define AVG        100  // Average sample limit
#define BUF_SIZE   100  // Sample buffer size

Uint16 SampleTable1[BUF_SIZE];

float Output1[BUF_SIZE];

void main(void)
{
       Uint16 i;
         
    InitSysCtrl();    // Basic Core Init from DSP2833x_SysCtrl.c  
      DINT;                // Disable all interrupts    
      Gpio_select();        // GPIO9, GPIO11, GPIO34 and GPIO49 as output
                        // to 4 LEDs at Peripheral Explorer)
    InitPieCtrl();        // basic setup of PIE table; from DSP2833x_PieCtrl.c
        
    // Disable CPU interrupts and clear all CPU interrupt flags:
       IER = 0x0000;
       IFR = 0x0000;
    
    InitPieVectTable();    // default ISR's in PIE

    InitAdc();            // Basic ADC setup, incl. calibration
    
    AdcRegs.ADCTRL1.all = 0;       
    AdcRegs.ADCTRL1.bit.ACQ_PS = 7;     // 7 = 8 x ADCCLK    
    AdcRegs.ADCTRL1.bit.SEQ_CASC =1;     // 1=cascaded sequencer
    AdcRegs.ADCTRL1.bit.CPS = 1;        // divide by 2
    AdcRegs.ADCTRL1.bit.CONT_RUN = 1;    // Continous run mode
    
    AdcRegs.ADCTRL2.all = 0;            
    AdcRegs.ADCTRL2.bit.SOC_SEQ1 = 1;    // 1=Software trigger
    AdcRegs.ADCTRL2.bit.EPWM_SOCA_SEQ1 =0;    // 0=SEQ1 cannot be started by ePWMx SOCA trigger.
    AdcRegs.ADCTRL2.bit.INT_MOD_SEQ1 = 0;    // 0= interrupt after every end of sequence
    
    AdcRegs.ADCTRL3.bit.ADCCLKPS = 3;    // ADC clock: FCLK = HSPCLK / 2 * ADCCLKPS

    AdcRegs.ADCMAXCONV.all = 0x0000;   
    AdcRegs.ADCCHSELSEQ1.bit.CONV00 = 0;
   
       
       for (i=0; i<AVG; i++)
     {
        while (AdcRegs.ADCST.bit.INT_SEQ1== 0) {} // Wait for interrupt
        AdcRegs.ADCST.bit.INT_SEQ1_CLR = 1;
        SampleTable1[i] =((AdcRegs.ADCRESULT0>>4) );
     
         if(SampleTable1[i]<685)
        { 
            GpioDataRegs.GPASET.bit.GPIO12 = 1;
        }
        else
        {           
            GpioDataRegs.GPASET.bit.GPIO12 = 0;
        }
        }  
       
     }
 
void Gpio_select(void)
{
    EALLOW;
    GpioCtrlRegs.GPAMUX1.all = 0;        // GPIO15 ... GPIO0 = General Puropse I/O
    GpioCtrlRegs.GPAMUX2.all = 0;        // GPIO31 ... GPIO16 = General Purpose I/O
    GpioCtrlRegs.GPBMUX1.all = 0;        // GPIO47 ... GPIO32 = General Purpose I/O
    GpioCtrlRegs.GPBMUX2.all = 0;        // GPIO63 ... GPIO48 = General Purpose I/O
    GpioCtrlRegs.GPCMUX1.all = 0;        // GPIO79 ... GPIO64 = General Purpose I/O
    GpioCtrlRegs.GPCMUX2.all = 0;        // GPIO87 ... GPIO80 = General Purpose I/O
    
    GpioCtrlRegs.GPADIR.all = 0;
        
    GpioCtrlRegs.GPBDIR.all = 0;        // GPIO63-32 as inputs

    GpioCtrlRegs.GPCDIR.all = 0;        
 
    GpioCtrlRegs.GPAMUX1.bit.GPIO12= 0; 
     GpioCtrlRegs.GPADIR.bit.GPIO12 = 1;  
 
    
       
    EDIS;
    
}