I want to measure the duty cycle of PWM, use the ECT function of mc9s12xep100, The fllowing is my code :
void ECT_Init(void)
{
ECT_TSCR2 = 0x80; // prescaller=1
ECT_TCTL3 = 0x04; // channel 5 input capture on rising edge
ECT_TIE = 0x20; // enable Ch5 interrupt
ECT_TSCR1 = 0xE0; // enable timer, stop during freeze and wait
}
#pragma CODE_SEG NON_BANKED
void interrupt 13 ECT4_ISR(void)
{
unsigned int ovfs;
TIM_TFLG1 = 0x20; // clear interrupt flag from PT5
}
#pragma CODE_SEG DEFAULT
#pragma CODE_SEG NON_BANKED
interrupt 16 void TIM_OvfIsr(void)
{
ch4ovfCnt++; // count overflows
ch5ovfCnt++;
ch6ovfCnt++;
ch7ovfCnt++;
TIM_TFLG2 = 0x80; // clear interrupt flag of main timer
}
#pragma CODE_SEG DEFAULT
I found that the flags of interupt can't be cleared causing the interrupt is always running.
Does my code have any problem?
how can I clear the flag of interrupt?
