刚接触dsp,不明白LED灯交替闪烁实验中为什么用epwm中断,请高手指点一下。 void main(void)
{Uint16 i = 0x55;
InitSysCtrl();
DINT;
InitPieCtrl();
IER = 0x0000;
IFR = 0x0000;
InitPieVectTable();
EALLOW; // This is needed to write to EALLOW protected registers
PieVectTable.EPWM1_INT = &epwm1_timer_isr;
PieVectTable.EPWM2_INT = &epwm2_timer_isr;
PieVectTable.EPWM3_INT = &epwm3_timer_isr;
EDIS; // This is needed to disable write to EALLOW protected registers
InitEPwmTimer(); // For this example, only initialize the ePWM Timers
//// This function must reside in RAM
InitFlash();
// Initalize counters:
EPwm1TimerIntCount = 0;
EPwm2TimerIntCount = 0;
EPwm3TimerIntCount = 0;
LoopCount = 0;
// Enable CPU INT3 which is connected to EPWM1-3 INT:
IER |= M_INT3;
// Enable EPWM INTn in the PIE: Group 3 interrupt 1-3
PieCtrlRegs.PIEIER3.bit.INTx1 = PWM1_INT_ENABLE;
PieCtrlRegs.PIEIER3.bit.INTx2 = PWM2_INT_ENABLE;
PieCtrlRegs.PIEIER3.bit.INTx3 = PWM3_INT_ENABLE;
// Enable global Interrupts and higher priority real-time debug events:
EINT; // Enable Global interrupt INTM
ERTM; // Enable Global realtime interrupt DBGM
//////Initial XZONE//////
InitXintf();
// Step 6. IDLE loop. Just sit and loop forever (optional):
for(;;)
{
// This loop will be interrupted, so the overall
// delay between pin toggles will be longer.
DELAY_US(DELAY);
LoopCount++;
LED = i;
i = ~i;
}
}
void InitEPwmTimer()
{
EALLOW;
SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 0; // Stop all the TB clocks
EDIS;
// Setup Sync
EPwm1Regs.TBCTL.bit.SYNCOSEL = TB_SYNC_IN; // Pass through
EPwm2Regs.TBCTL.bit.SYNCOSEL = TB_SYNC_IN; // Pass through
EPwm3Regs.TBCTL.bit.SYNCOSEL = TB_SYNC_IN; // Pass through
// Allow each timer to be sync'ed
EPwm1Regs.TBCTL.bit.PHSEN = TB_ENABLE;
EPwm2Regs.TBCTL.bit.PHSEN = TB_ENABLE;
EPwm3Regs.TBCTL.bit.PHSEN = TB_ENABLE;
EPwm1Regs.TBPHS.half.TBPHS = 100;
EPwm2Regs.TBPHS.half.TBPHS = 200;
EPwm3Regs.TBPHS.half.TBPHS = 300;
EPwm1Regs.TBPRD = PWM1_TIMER_TBPRD;
EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UP; // Count up
EPwm1Regs.ETSEL.bit.INTSEL = ET_CTR_ZERO; // Select INT on Zero event
EPwm1Regs.ETSEL.bit.INTEN = PWM1_INT_ENABLE; // Enable INT
EPwm1Regs.ETPS.bit.INTPRD = ET_1ST; // Generate INT on 1st event
EPwm2Regs.TBPRD = PWM2_TIMER_TBPRD;
EPwm2Regs.TBCTL.bit.CTRMODE = TB_COUNT_UP; // Count up
EPwm2Regs.ETSEL.bit.INTSEL = ET_CTR_ZERO; // Enable INT on Zero event
EPwm2Regs.ETSEL.bit.INTEN = PWM2_INT_ENABLE; // Enable INT
EPwm2Regs.ETPS.bit.INTPRD = ET_2ND; // Generate INT on 2nd event
EPwm3Regs.TBPRD = PWM3_TIMER_TBPRD;
EPwm3Regs.TBCTL.bit.CTRMODE = TB_COUNT_UP; // Count up
EPwm3Regs.ETSEL.bit.INTSEL = ET_CTR_ZERO; // Enable INT on Zero event
EPwm3Regs.ETSEL.bit.INTEN = PWM3_INT_ENABLE; // Enable INT
EPwm3Regs.ETPS.bit.INTPRD = ET_3RD; // Generate INT on 3rd event
EALLOW;
SysCtrlRegs.PCLKCR0.bit.TBCLKSYNC = 1; // Start all the timers synced
EDIS;
}
// This ISR MUST be executed from RAM as it will put the Flash into Sleep
// Interrupt routines uses in this example:
interrupt void epwm1_timer_isr(void)
{
// Put the Flash to sleep
FlashRegs.FPWR.bit.PWR = FLASH_SLEEP;
EPwm1TimerIntCount++;
// Clear INT flag for this timer
EPwm1Regs.ETCLR.bit.INT = 1;
// Acknowledge this interrupt to receive more interrupts from group 3
PieCtrlRegs.PIEACK.all = PIEACK_GROUP3;
}
// This ISR MUST be executed from RAM as it will put the Flash into Standby
interrupt void epwm2_timer_isr(void)
{
EPwm2TimerIntCount++;
// Put the Flash into standby
FlashRegs.FPWR.bit.PWR = FLASH_STANDBY;
// Clear INT flag for this timer
EPwm2Regs.ETCLR.bit.INT = 1;
// Acknowledge this interrupt to receive more interrupts from group 3
PieCtrlRegs.PIEACK.all = PIEACK_GROUP3;
}
interrupt void epwm3_timer_isr(void)
{
Uint16 i;
EPwm3TimerIntCount++;
// Short Delay to simulate some ISR Code
for(i = 1; i < 0x01FF; i++) {}
// Clear INT flag for this timer
EPwm3Regs.ETCLR.bit.INT = 1;
// Acknowledge this interrupt to receive more interrupts from group 3
PieCtrlRegs.PIEACK.all = PIEACK_GROUP3;
} |