#include <avr/io.h>#include <avr/wdt.h>#include <avr/pgmspace.h>#include <stdlib.h>#include <avr/interrupt.h>#include "config.h"#include "ad7714.h"// These are suitable for a clock rate of 2.4576MHz and// a powerline frequency of 60Hz.uint16_t ADC_RATES[] = { 4000, 3840, 1920, 1280, 960, 640, 320, 160, 80, 40, 20, 0 }; // FIXME - used but not changed in ISR - volatile needed?static volatile ad7714params_t params;static volatile uint32_t av_accum=0;static volatile uint8_t av_count=0;static volatile uint8_t num_captures=0;static volatile uint32_t last_capture=0;static volatile uint8_t can_set_params=0;static void captureEnable(uint8_t state) {#if ADC_USE_ISR	if(state) EIMSK |=  _BV(INT0);	else      EIMSK &= ~_BV(INT0);#endif}static uint8_t SPI(uint8_t v) {	ADC_CS_PORT &= ~_BV(ADC_CS_BIT); // clear !SS	SPDR = v;	while(!(SPSR & (1<<SPIF)));	uint8_t ret = SPDR;	ADC_CS_PORT |= _BV(ADC_CS_BIT); // set !SS	return ret;}static void grabport() {	SPCR |= (_BV(CPOL) | _BV(CPHA));}static void freeport() {}static void writereg(uint8_t reg, uint8_t chan, uint8_t len, uint32_t data) {	uint8_t cr = (reg << 4) | chan;	SPI(cr);	while(len) {		len--;		SPI(data >> (len * 8));	}}static uint32_t readreg(uint8_t reg, uint8_t chan, uint8_t len) {	uint8_t cr = (reg << 4) | 0x8 | chan;	SPI(cr);	uint32_t data = 0;	while(len) {		len--;		data <<= 8;		data |= SPI(0);	}	return data;}static void reset_serial() {	SPI(0xff); SPI(0xff); SPI(0xff); SPI(0xff);}void ad7714init() {	captureEnable(0);	ADC_CS_DDR |= _BV(ADC_CS_BIT);#if ADC_USE_ISR	EICRA &= ~(_BV(ISC00) | _BV(ISC01));	DDRD &= ~_BV(PD2); // DRDY pin from ADC#endif#ifdef ADC_BUFFER_BIT	ADC_BUFFER_DDR |= _BV(ADC_BUFFER_BIT);#endif	grabport();	reset_serial();// Calibrate all channels ahead of time:// (this doesn't work so just call ad7714setup on demand)//	uint8_t chan;//	for(chan=0; chan<8; chan++) {//		ad7714setup(chan, 1, 4000);//	}	freeport();}void ad7714setup(ad7714params_t new_params) {	captureEnable(0);	grabport();	params = new_params;	// limit bits for safety	params.chan &= 7;	params.gain_param &= 7;	params.rate &= 0xfff;	reset_serial();	// gain = (2 ** gain_param), so gain_param>2 means a gain of more than 4	uint8_t boost_bit = (params.gain_param > 2) ? 0x20 : 0x00;	writereg(2, params.chan, 1, 0x40 | boost_bit | (params.rate >> 8)); // filter hi	writereg(3, params.chan, 1, (params.rate & 0xff)); // filter lo	writereg(1, params.chan, 1, 0x20 | (params.gain_param<<2));	num_captures = 0;	av_count = 0;	// can't set params again till data comes in (don't know why)	can_set_params = 0;	freeport();	captureEnable(1);}static uint8_t check_ready_reg() {	grabport();	uint8_t status = readreg(0, params.chan, 1);	// not needed per spec, but it helps to fix comm errors	while((status & 0xf) != (0x8 | params.chan)) {		reset_serial();		status = readreg(0, params.chan, 1);	}	uint8_t ready = !(status & 0x80);	freeport();	return ready;}static uint32_t read_data_reg() {	grabport();	uint32_t ret = readreg(5, params.chan, 3);	freeport();	return ret;}static void update_if_avail() {	if(check_ready_reg()) {		last_capture = read_data_reg();		can_set_params = 1;		if(num_captures < 255) num_captures++;		if(av_count < 255) {			av_accum += last_capture;			av_count++;		}	}}#if ADC_USE_ISRISR(INT0_vect) {	// This pin is always low in this interrupt handler	//uint8_t ready = !(PIND & _BV(PD2));	//if(ready)	update_if_avail();}#endifuint8_t ad7714have_capture() {#if ADC_USE_ISR	return num_captures;#else	return check_ready_reg();#endif}uint32_t ad7714get_capture() {	captureEnable(0);#if !ADC_USE_ISR	update_if_avail();#endif	uint32_t ret = last_capture;	num_captures=0;	captureEnable(1);	return ret;}uint8_t ad7714accum_count() {	return av_count;}uint32_t ad7714pull_average() {	captureEnable(0);	uint32_t ret = av_accum / av_count;	av_count = 0;	av_accum = 0;	captureEnable(1);	return ret;}#ifdef ADC_BUFFER_BITvoid ad7714set_buffer(uint8_t state) {	if(state) ADC_BUFFER_PORT |=  _BV(ADC_BUFFER_BIT);	else      ADC_BUFFER_PORT &= ~_BV(ADC_BUFFER_BIT);}#endifuint8_t ad7714can_set_params() {	return can_set_params;}char *ad7714chan_name(uint8_t chan) {	switch(chan) {		case 0: return "AIN1-AIN6";		case 1: return "AIN2-AIN6";		case 2: return "AIN3-AIN6";		case 3: return "AIN4-AIN6";		case 4: return "AIN1-AIN2";		case 5: return "AIN3-AIN4";		case 6: return "AIN5-AIN6";		case 7: return "AIN6-AIN6";		default: return "invalid";	}}double ad7714rate_to_hertz(uint16_t rate) {	return (double)(F_ADC / 128) / (double)rate;}uint16_t ad7714standard_rate(uint8_t idx) {	return ADC_RATES[idx];}