CCS/TMDSDOCK28335: pwm from given dc signal provided to adc pin

Tool/software: Code Composer Studio

Sir/Madam

I am learning  tms28335 experimental kit. My aim is to give the analog D.C signal from signal generator to adc pin A0 and observe the pulse from the controller. I dont know where ie the problem. I am copying the code below.

#include"DSP2833x_Device.h"
#include"math.h"

// external function prototypes
extern void InitAdc(void);
extern void InitSysCtrl(void);
extern void InitPieCtrl(void);
extern void InitPieVectTable(void);

// Prototype statements for functions found within this file.
void Gpio_select(void);
void Setup_ePWM1(void);
interrupt void adc_isr(void); // ADC End of Sequence ISR

// Global Variables
Uint16 pwm=750;
float Voltage_VR1;
float duty_pwm;

//###########################################################################
// main code
//###########################################################################
void main(void)
{
InitSysCtrl(); // Basic Core Init from DSP2833x_SysCtrl.c

EALLOW;
SysCtrlRegs.WDCR= 0x00AF; // Re-enable the watchdog
EDIS; // 0x00AF to NOT disable the Watchdog, Prescaler = 64

DINT; // Disable all interrupts

Gpio_select(); // GPIO9, GPIO11, GPIO34 and GPIO49 as output
// to 4 LEDs at Peripheral Explorer)

Setup_ePWM1(); // init of ePWM1A

InitPieCtrl(); // basic setup of PIE table; from DSP2833x_PieCtrl.c

InitPieVectTable(); // default ISR's in PIE

InitAdc(); // Basic ADC setup, incl. calibration

AdcRegs.ADCTRL1.all = 0;
AdcRegs.ADCTRL1.bit.ACQ_PS = 1; // 7 = 8 x ADCCLK
AdcRegs.ADCTRL1.bit.SEQ_CASC =0; // 1=cascaded sequencer
AdcRegs.ADCTRL1.bit.CPS = 0; // divide by 1
AdcRegs.ADCTRL1.bit.CONT_RUN = 0; // single run mode

AdcRegs.ADCTRL2.all = 0;
AdcRegs.ADCTRL2.bit.INT_ENA_SEQ1 = 1; // 1=enable SEQ1 interrupt
AdcRegs.ADCTRL2.bit.EPWM_SOCA_SEQ1 =1; // 1=SEQ1 start from ePWM_SOCA trigger
AdcRegs.ADCTRL2.bit.INT_MOD_SEQ1 = 0; // 0= interrupt after every end of sequence

AdcRegs.ADCTRL3.bit.ADCCLKPS = 2; // ADC clock: FCLK = HSPCLK / 2 * ADCCLKPS
// HSPCLK = 75MHz (see DSP2833x_SysCtrl.c)
// FCLK = 12.5 MHz

AdcRegs.ADCMAXCONV.all = 0; // 1 conversion from Sequencer 1

AdcRegs.ADCCHSELSEQ1.bit.CONV00 = 0; // Setup ADCINA0 as 1st SEQ1 conv.

EALLOW;
PieVectTable.ADCINT = &adc_isr;
EDIS;

PieCtrlRegs.PIEIER1.bit.INTx7 = 1; // CPU Timer 0
PieCtrlRegs.PIEIER1.bit.INTx6 = 1; // ADC

IER |=1;

EINT;
ERTM;
}

void Gpio_select(void)
{
EALLOW;
GpioCtrlRegs.GPAMUX1.all = 0; // GPIO15 ... GPIO0 = General Puropse I/O
GpioCtrlRegs.GPAMUX1.bit.GPIO0 = 1; // ePWM1A active

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.GPADIR.bit.GPIO9 = 1; // peripheral explorer: LED LD1 at GPIO9
GpioCtrlRegs.GPADIR.bit.GPIO31 = 1; // peripheral explorer: LED LD2 at GPIO11

GpioCtrlRegs.GPBDIR.all = 0; // GPIO63-32 as inputs
GpioCtrlRegs.GPBDIR.bit.GPIO34 = 1; // peripheral explorer: LED LD3 at GPIO34
GpioCtrlRegs.GPBDIR.bit.GPIO49 = 1; // peripheral explorer: LED LD4 at GPIO49
GpioCtrlRegs.GPCDIR.all = 0; // GPIO87-64 as inputs
EDIS;
}

interrupt void adc_isr(void)
{
Voltage_VR1 = (AdcMirror.ADCRESULT0); // store result global
// Reinitialize for next ADC sequence
AdcRegs.ADCTRL2.bit.RST_SEQ1 = 1; // Reset SEQ1
AdcRegs.ADCST.bit.INT_SEQ1_CLR = 1; // Clear INT SEQ1 bit
PieCtrlRegs.PIEACK.all = PIEACK_GROUP1; // Acknowledge interrupt to PIE
}

void Setup_ePWM1(void)
{
EPwm1Regs.ETSEL.bit.SOCAEN = 1; // Enable SOC on A group
EPwm1Regs.ETSEL.bit.SOCASEL = 1; // Select SOC from from CPMA on upcount
EPwm1Regs.ETPS.bit.SOCAPRD = 1; // Generate pulse on 1st event
EPwm1Regs.TBCTL.bit.CLKDIV = 0; // CLKDIV = 1
EPwm1Regs.TBCTL.bit.HSPCLKDIV = 0; // HSPCLKDIV = 2
EPwm1Regs.TBCTL.bit.CTRMODE = 2; // up - down mode

EPwm1Regs.AQCTLA.bit.CAU = 2; // set ePWM1A on CMPA up
// clear ePWM1A on CMPA down

EPwm1Regs.AQCTLA.bit.CAD = 1; // set ePWM1B on CMPB up
// clear ePWM1B on CMPB down

duty_pwm = pwm*(Voltage_VR1)/4096;  
EPwm1Regs.CMPA.half.CMPA = duty_pwm; 
}

//===========================================================================
// End of SourceCode.
//===========================================================================