EscharotomyArm.c

#include "EscharotomyArm.h"

volatile uint8_t pulse_enabled;
void heat_enable(void)
{
	PORTB |= (1<<PB7);
}

void heat_disable(void)
{
	PORTB &= ~(1<<PB7);
}

void eschar_task(uint16_t* adc_values)
{
#define ETASK_EL(x) if ((!eschar_msg_state_##x) && (adc_values[ESCHAR_PIN_##x]<ESCHAR_CUT_THRESH)) {\
			eschar_msg_state_##x = ESCHAR_MSG_WAITING;\
		}
	/*
	if (!eschar_msg_state_1 && !adc_values[ESCHAR_PIN_1]) {
			eschar_msg_state_1 = ESCHAR_MSG_WAITING;
	}
	*/
	ETASK_EL(1);
	ETASK_EL(2);
	ETASK_EL(3);
	ETASK_EL(4);
	ETASK_EL(5);
	
	if (eschar_msg_state_1 || eschar_msg_state_2
		|| eschar_msg_state_3 || eschar_msg_state_4
		|| eschar_msg_state_5) {
		heat_enable();
	}
	int numcut = (!!eschar_msg_state_1) + (!!eschar_msg_state_2)
		+ (!!eschar_msg_state_3) + (!!eschar_msg_state_4)
		+ (!!eschar_msg_state_5);
	if (numcut >= 4 && !pulse_enabled) {
		pulse_init();
	}
	
}

void eschar_init(void)
{
	//set timer to fast pwm mode
	//page 131 for COM info 
	//see datasheet page 133 for WGM info
	//page 134 for CS (clock select) info
	TCCR1A = (1<<WGM11) | (1<<WGM10) | (1<<COM1B1);
	TCCR1B = (1<<WGM13) | (1<<WGM12) | (1<<CS10);
	
	//enable interrupts on timer
	//TIMSK1 = (1<<OCIE1A);
	
	//set TOP value to determine frequency
	OCR1A = 0xff;
	//freq = 16000000 * 256 = 62500Hz
	//set duty cycle
	OCR1B = 0x00;
	
	//enable output on appropriate pin (B6) and also for the MOSFET (B7)
	DDRB |= (1<<PB6) | (1<<PB7);
	//PORTB |= (1<<PB7);
	
}


//the heartbeat could be done with an interrupt as well.
//plan for heartbeat
//make lookup table of one-byte duty cycle values for each quarter millisecond
//in the beat duration. Also have a value for the normal voltage (as a duty cycle, of course)
//not in PROGMEM because we're going to generate it dynamically
#define PULSE_NUM_ELTS 68
const uint8_t pulse[PULSE_NUM_ELTS] = 
	{0x2a,0x29,0x28,0x27,0x26,0x25,0x24,0x23,0x22,0x21,0x20,0x1f,0x28,0x33,0x3e,0x49,0x54,0x5f,0x6a,0x76,0x81,0x8c,0x97,0xa2,0xad,0xb8,0xc3,0xcf,0xda,0xe5,0xf0,0xfb,0xf9,0xef,0xe5,0xdb,0xd1,0xc7,0xbe,0xb4,0xaa,0xa0,0x96,0x8c,0x83,0x79,0x6f,0x65,0x5b,0x52,0x48,0x3e,0x34,0x2a,0x20,0x20,0x21,0x22,0x23,0x24,0x25,0x26,0x27,0x28,0x29,0x2b,0x2c,0x2d}
;
#define DEFAULT_PULSE_LEVEL 31
ms_time_t last_loop_start;

int pulse_delay_ms = 1000 - PULSE_NUM_ELTS;
void pulse_init(void)
{
	last_loop_start = millis();
	pulse_enabled = 1;
}
void pulse_stop(void)
{
	pulse_enabled = 0;
}
void pulse_set_delay(int delay)
{
	pulse_enabled = 1;
	if (delay > PULSE_NUM_ELTS) {
		pulse_delay_ms = delay;
	} else {
		pulse_delay_ms = PULSE_NUM_ELTS; // FIXME 50% seems a good choice
	}
}
void pulse_task(void)
{
	if (pulse_enabled) {
		ms_time_t now = millis();
		ms_time_t offset = (now - last_loop_start) % pulse_delay_ms;
		uint8_t val = DEFAULT_PULSE_LEVEL;
		if (offset < PULSE_NUM_ELTS) {
			val = pulse[offset];
		}
		OCR1B = val;
	} else {
		OCR1B = 0;
	}
}