ppmsum.cpp


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#include "ppmsum.h"

PPMSum* PPMSum::self = 0;

template<>
void interrupt<Interrupt::TIM4>() {
	PPMSum::self->irq();
}

void PPMSum::irq() {
	int16_t sr = TIM4.SR;
	TIM4.SR = 0;
	
	if(sr & 0x06) {
		GPIOA.ODR = 1 << 5;
	} else {
		GPIOA.ODR = 0;
	}
	
	
	if(sr & 0x01) {
		// Timeout.
		
		// TODO: Indicate failsafe.
		
	} else if(sr & 0x02) {
		// Period.
		
		if(TIM4.CCR1 > 5000) {
			index = 0;
		} else {
			index++;
		}
		
	} else if(sr & 0x04) {
		// Pulsewidth.
		
		channels[index] = TIM4.CCR2;
	}
}

void PPMSum::enable() {
	RCC.enable(RCC.TIM4);
	TIM4.PSC = 36;
	TIM4.CCMR1 = 0x0201;
	TIM4.SMCR = 0x54;
	TIM4.CCER = 0x31;
	TIM4.DIER = 0x07;
	
	Interrupt::enable(Interrupt::TIM4);
	
	TIM4.CR1 = 0x05;
}