TMS320F28335 How to make logic connection in between two PWM signals

Hello,

I am generating three PWM singles using an interrupt routine, the three signals are 120 degree phase shift from each other!

My question is: how can I make logical connection in between those signals (A,B,C)and generate fourth signal(D).

for example  if A, B, and C are 1,1 and 1, then the fourth signal is 1.

I just don't know how can I do that! ...... Its important to know that I don't want the three signal as an output, I just want to use them in internal operations and produce the fourth signal as an out put!

the current code that generate and output the three signals (A, B, C) is provided below!

//
//    : TMS320F28335
//      (c) Frank Bormann
//
//###########################################################################
//
// FILE: Lab7_2.c
//
// TITLE: DSP28335ControlCARD;
//   3 phase signal system
//   1KHz output at ePWM1A, ePWM2A and ePWM3A
//   solution file for Lab7_2
//###########################################################################
//  Ver | dd mmm yyyy | Who  | Description of changes
// =====|=============|======|===============================================
//  3.0 | 14 Apr 2009 | F.B. | Lab7_2 for F28335;
//  3.1 | 09 Nov 2009 | F.B  | Lab7_2 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_ePWM(void);
interrupt void cpu_timer0_isr(void);

//###########################################################################
//      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)

 Setup_ePWM();  // init of ePWM1, ePWM2 and ePWM3

 InitPieCtrl();  // basic setup of PIE table; from DSP2833x_PieCtrl.c
 
 InitPieVectTable(); // default ISR's in PIE

 EALLOW;
 PieVectTable.TINT0 = &cpu_timer0_isr;
 EDIS;

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

 ConfigCpuTimer(&CpuTimer0,150,100000);

 PieCtrlRegs.PIEIER1.bit.INTx7 = 1;

 IER |=1;

 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.GPAMUX1.bit.GPIO2 = 1; // ePWM2A active
 GpioCtrlRegs.GPAMUX1.bit.GPIO4 = 1; // ePWM3A 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.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_ePWM(void)
{
 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

 EPwm2Regs.TBCTL.bit.CLKDIV =  0; // CLKDIV = 1  
 EPwm2Regs.TBCTL.bit.HSPCLKDIV = 1; // HSPCLKDIV = 1
 EPwm2Regs.TBCTL.bit.CTRMODE = 2; // up - down mode
 EPwm2Regs.AQCTLA.all = 0x0006;  // ZRO = set, PRD = clear
 EPwm2Regs.TBPRD = 37500;   // 1KHz - PWM signal

 EPwm3Regs.TBCTL.bit.CLKDIV =  0; // CLKDIV = 1  
 EPwm3Regs.TBCTL.bit.HSPCLKDIV = 1; // HSPCLKDIV = 1
 EPwm3Regs.TBCTL.bit.CTRMODE = 2; // up - down mode
 EPwm3Regs.AQCTLA.all = 0x0006;  // ZRO = set, PRD = clear
 EPwm3Regs.TBPRD = 37500;   // 1KHz - PWM signal
 
 EPwm1Regs.TBCTL.bit.SYNCOSEL = 1; // generate a syncout if CTR = 0

 EPwm2Regs.TBCTL.bit.PHSEN = 1;  // enable phase shift for ePWM2
 EPwm2Regs.TBCTL.bit.SYNCOSEL = 0; // syncin = syncout
 EPwm2Regs.TBPHS.half.TBPHS = 12500; // 1/3 phase shift

 EPwm3Regs.TBCTL.bit.PHSEN = 1;  // enable phase shift for ePWM3
 EPwm3Regs.TBPHS.half.TBPHS = 25000; // 2/3 phase shift

}

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