TMS320F28335: TMS320F28333

I have performed lab 7_10 to capture the digital signal from EPWM1A (GPIO00) using the eCap module and measure the duty cycle and the period on simulator through watch window. Here GPIO00 EPWM is connected to GPIO24. This lab works very well.

Now my task is to capture the digital signals externally with different duty cycle as INPUT, (not from EPWM GPIO0)  and measure the duty cycle and the period on simulator through watch window and then generate two complementary epwm signals as OUTPUT at GPIO2 EPWM2A and GPIO4 EPWM3A with same measured duty cycle and the period respectively.

What changes do i need to do in lab 7_10 to perform above task? Community members please suggest

Lab 7_10 code:

//
// Lab7_10: TMS320F28335
// (c) Frank Bormann
//
//###########################################################################
//
// FILE: Lab7_10.c
//
// TITLE: DSP28335ControlCARD; ePWM1A 1KHz output
// and measurement with eCAP1
// solution file for Lab7_10
//###########################################################################
// Ver | dd mmm yyyy | Who | Description of changes
// =====|=============|======|===============================================
// 3.0 | 12 May 2009 | F.B. | Lab7_10 for F28335;
// 3.1 | 11 Nov 2009 | F.B | Lab7_10 for F28335 and PE Revision 5
//###########################################################################
#include "DSP2833x_Device.h"

// external function prototypes
extern void InitSysCtrl(void);
extern void InitPieCtrl(void);
extern void InitPieVectTable(void);
extern void InitCpuTimers(void);
extern void ConfigCpuTimer(struct CPUTIMER_VARS *, float, float);

// Prototype statements for functions found within this file.
void Gpio_select(void);
void Setup_ePWM1A(void);
void Setup_eCAP1(void);
interrupt void cpu_timer0_isr(void);
interrupt void eCAP1_isr(void);

// Global Variables
Uint32 PWM_Duty;
Uint32 PWM_Period;

//###########################################################################
// main code
//###########################################################################
void main(void)
{
int counter=0; // binary counter for digital output

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 Board

Setup_ePWM1A(); // init ePWM1A

Setup_eCAP1(); // init eCAP1

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

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

EALLOW;
PieVectTable.TINT0 = &cpu_timer0_isr;
PieVectTable.ECAP1_INT= &eCAP1_isr;
EDIS;

InitCpuTimers(); // basic setup CPU Timer0, 1 and 2

ConfigCpuTimer(&CpuTimer0,150,100000);

PieCtrlRegs.PIEIER1.bit.INTx7 = 1; // Enable CPU Timer 0 INT
PieCtrlRegs.PIEIER4.bit.INTx1 = 1; // Enable ECAP1_INT in PIE group 4
IER |= 0x0009; // Enable INT4 and INT1

EINT;
ERTM;

CpuTimer0Regs.TCR.bit.TSS = 0; // start timer0

while(1)
{
while(CpuTimer0.InterruptCount == 0);
CpuTimer0.InterruptCount = 0;

EALLOW;
SysCtrlRegs.WDKEY = 0x55; // service WD #1
EDIS;

counter++;
if(counter&1) GpioDataRegs.GPASET.bit.GPIO9 = 1;
else GpioDataRegs.GPACLEAR.bit.GPIO9 = 1;
if(counter&2) GpioDataRegs.GPASET.bit.GPIO11 = 1;
else GpioDataRegs.GPACLEAR.bit.GPIO11 = 1;
if(counter&4) GpioDataRegs.GPBSET.bit.GPIO34 = 1;
else GpioDataRegs.GPBCLEAR.bit.GPIO34 = 1;
if(counter&8) GpioDataRegs.GPBSET.bit.GPIO49 = 1;
else GpioDataRegs.GPBCLEAR.bit.GPIO49 = 1;
}
}

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.GPAMUX2.bit.GPIO24= 1; // eCAP1 active
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.GPIO11 = 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;
}

void Setup_ePWM1A(void)
{
EPwm1Regs.TZCTL.all = 0;
EPwm1Regs.TBCTL.bit.CLKDIV = 0; // CLKDIV = 1
EPwm1Regs.TBCTL.bit.HSPCLKDIV = 1; // HSPCLKDIV = 2
EPwm1Regs.TBCTL.bit.CTRMODE = 2; // up - down mode
EPwm1Regs.AQCTLA.all = 0x0006; // ZRO = set, PRD = clear
EPwm1Regs.TBPRD = 37500; // 1KHz - PWM signal

}

void Setup_eCAP1(void)
{
//---------------------------------------------------------------------
//--- Configure eCAP1 unit for capture
//---------------------------------------------------------------------
ECap1Regs.ECEINT.all = 0; // Disable all eCAP interrupts
ECap1Regs.ECCTL1.bit.CAPLDEN = 0; // Disabled loading of capture results
ECap1Regs.ECCTL2.bit.TSCTRSTOP = 0; // Stop the counter

ECap1Regs.TSCTR = 0; // Clear the counter
ECap1Regs.CTRPHS = 0; // Clear the counter phase register

ECap1Regs.ECCTL2.all = 0x0096; // ECAP control register 2
// bit 15-11 00000: reserved
// bit 10 0: APWMPOL, don't care
// bit 9 0: CAP/APWM, 0 = capture mode, 1 = APWM mode
// bit 8 0: SWSYNC, 0 = no action (no s/w synch)
// bit 7-6 10: SYNCO_SEL, 10 = disable sync out signal
// bit 5 0: SYNCI_EN, 0 = disable Sync-In
// bit 4 1: TSCTRSTOP, 1 = enable counter
// bit 3 0: RE-ARM, 0 = don't re-arm, 1 = re-arm
// bit 2-1 11: STOP_WRAP, 11 = wrap after 4 captures
// bit 0 0: CONT/ONESHT, 0 = continuous mode

ECap1Regs.ECCTL1.all = 0x01C4; // ECAP control register 1
// bit 15-14 00: FREE/SOFT, 00 = stop TSCTR immediately
// bit 13-9 00000: PRESCALE, 00000 = divide by 1
// bit 8 1: CAPLDEN, 1 = enable capture results load
// bit 7 1: CTRRST4, 1 = reset counter on CAP4 event
// bit 6 1: CAP4POL, 0 = rising edge, 1 = falling edge
// bit 5 0: CTRRST3, 0 = do not reset counter on CAP3 event
// bit 4 0: CAP3POL, 0 = rising edge, 1 = falling edge
// bit 3 0: CTRRST2, 0 = do not reset counter on CAP2 event
// bit 2 1: CAP2POL, 0 = rising edge, 1 = falling edge
// bit 1 0: CTRRST1, 0 = do not reset counter on CAP1 event
// bit 0 0: CAP1POL, 0 = rising edge, 1 = falling edge

ECap1Regs.ECEINT.all = 0x0008; // Enable desired eCAP interrupts
// bit 15-8 0's: reserved
// bit 7 0: CTR=CMP, 0 = compare interrupt disabled
// bit 6 0: CTR=PRD, 0 = period interrupt disabled
// bit 5 0: CTROVF, 0 = overflow interrupt disabled
// bit 4 0: CEVT4, 0 = event 4 interrupt disabled
// bit 3 1: CEVT3, 1 = event 3 interrupt enabled
// bit 2 0: CEVT2, 0 = event 2 interrupt disabled
// bit 1 0: CEVT1, 0 = event 1 interrupt disabled
// bit 0 0: reserved

}

interrupt void cpu_timer0_isr(void)
{
CpuTimer0.InterruptCount++;
EALLOW;
SysCtrlRegs.WDKEY = 0xAA; // service WD #2
EDIS;
PieCtrlRegs.PIEACK.all = PIEACK_GROUP1;
}

interrupt void eCAP1_isr(void)
{
ECap1Regs.ECCLR.bit.INT = 1; // Clear the ECAP1 interrupt flag
ECap1Regs.ECCLR.bit.CEVT3 = 1; // Clear the CEVT3 flag

// Calculate the PWM duty period (rising edge to falling edge)
PWM_Duty = (int32)ECap1Regs.CAP2 - (int32)ECap1Regs.CAP1;

// Calculate the PWM period (rising edge to rising edge)
PWM_Period = (int32)ECap1Regs.CAP3 - (int32)ECap1Regs.CAP1;

PieCtrlRegs.PIEACK.all = PIEACK_GROUP4; // Must acknowledge the PIE group 4
}
//===========================================================================
// End of SourceCode.
//===========================================================================