rusefi/firmware/controllers/serial/serial_sensor.cpp

/**
 * @file	serial_sensor.cpp
 *
 *
 * @date Mar 19, 2020
 * @author Konstantin Smola, (c) 2020
 */

#include "pch.h"

#if EFI_AUX_SERIAL
#include "serial.h"
#include "serial_sensor.h"

#define NUM_INNOVATE_O2_SENSORS 1
#define AFR_MULTIPLIER 147

volatile float InnovateLC2AFR = AFR_ERROR;

typedef enum
{
	NO_ERROR = 0,
	HEATER_SHORTED = 1,
	HEATER_OPEN = 2,
	PUMPCELL_SHORTED = 3,
	PUMPCELL_OPEN = 4,
	REFCELL_SHORTED = 5,
	REFCELL_OPEN = 6,
	SYSTEM_ERROR = 7,
	SENSOR_TIMING_ERR = 8,
	SUPP_V_LOW = 9
} sensor_error_code_t;

struct sensor_data_t {
	int function_code;
	float AFR;
	float AFR_multiplier;
	float lambda;
	float warmup;
	sensor_error_code_t error_code;
};

static sensor_data_t innovate_o2_sensor[NUM_INNOVATE_O2_SENSORS];

static size_t tmsglen;

void IdentifyInnovateSerialMsg() {		//this identifies an innovate LC1/LC2 o2 sensor by it's first word (header)
	if (engineConfiguration->enableInnovateLC2) {
		if ((((ser_buffer[0]) & lc2_header_mask) != lc2_header_mask) && innovate_serial_id_state == IDENTIFIED) {		//not serial header word
			innovate_serial_id_state = UNKNOWN;
			innovate_msg_len = 1;
			sb = 0;
		}

		switch (innovate_serial_id_state) {
		case UNKNOWN:
			InnovateLC2AFR = AFR_ERROR;
			// read one byte, identify with mask, advance and read next byte
			if (((ser_buffer[0]) & lc2_header_mask) == lc2_header_mask) { // check if it's the first byte of header
				// first byte identified, now continue reading and advance statemachine
				innovate_serial_id_state = HEADER_FOUND;
				innovate_msg_len = 1;
				sb = 1;
			} else {
				innovate_serial_id_state = UNKNOWN;
			}
			break;

		case HEADER_FOUND:
			// now we should have both header bytes in array, and we can read the total packet length
			tmsglen = (((ser_buffer[0] << 8) | ser_buffer[1]) & lc2_pcklen_mask); //0000000101111111 mask

			if (tmsglen) {
				tmsglen += 1; // length in words including header (2 bytes)
				tmsglen *= 2; // length in bytes (incl header)
				innovate_msg_len = tmsglen - 2;
				sb = 2;
				innovate_serial_id_state = IDENTIFIED; //advance state machine
			} else {
				innovate_serial_id_state = UNKNOWN;
			}

			break;

		case IDENTIFIED:
		    innovate_msg_len = tmsglen;
			sb = 0;
			// serial packet fully identified
			ParseInnovateSerialMsg(); //takes about 570ns
			clear_ser_buffer = true;
			break;

		default:
			break;
		}
	}
}

void ParseInnovateSerialMsg() {
	float raw_afr;
	//get error code and afr

	// 000 Lambda valid and Aux data valid, normal operation.
	// 001 Lambda value contains O2 level in 1/10%
	// 010 Free air Calib in progress, Lambda data not valid
	// 011 Need Free air Calibration Request, Lambda data not valid
	// 100 Warming up, Lambda value is temp in 1/10% of operating temp.
	// 101 Heater Calibration, Lambda value contains calibration countdown.
	// 110 Error code in Lambda value
	// 111 reserved

	for (size_t i = 0; i < ((tmsglen - 2) / 4) && i < NUM_INNOVATE_O2_SENSORS; i++) {
		innovate_o2_sensor[i].function_code = (ser_buffer[2 + i * 4] >> 2 & 0x7);
		// innovate_o2_sensor[i].AFR_multiplier = ((ser_buffer[2 + i * 4] << 7 | ser_buffer[3 + i * 4]) & 0xFF);
		innovate_o2_sensor[i].AFR_multiplier = AFR_MULTIPLIER;

		switch (innovate_o2_sensor[i].function_code) {
		case 0: //Lambda valid and aux data valid, normal operation
		case 1: //Lambda value contains o2 level in 1/10%
			innovate_o2_sensor[i].lambda = ((ser_buffer[4 + i * 4] << 7 | ser_buffer[5 + i * 4]) & 0x1FFF);
			raw_afr = ((innovate_o2_sensor[i].lambda + 500) * innovate_o2_sensor[i].AFR_multiplier);

			if (innovate_o2_sensor[i].function_code) {//case 1
				innovate_o2_sensor[i].AFR = raw_afr * 0.001;
			} else { // case 0
				innovate_o2_sensor[i].AFR = raw_afr * 0.0001;
			}

			if (innovate_o2_sensor[i].AFR > AFRMAX) {
				innovate_o2_sensor[i].AFR = AFRMAX;
			} else if (innovate_o2_sensor[i].AFR < AFRMIN) {
				innovate_o2_sensor[i].AFR = AFRMIN;
		    }

			InnovateLC2AFR = innovate_o2_sensor[0].AFR; //only using one sensor right now

			break;
		// this is invalid o2 data, so we can ignore it:
		//  case 2: // Free air Calib in progress, Lambda data not valid
		//    break;
		//  case 3: // Need Free air Calibration Request, Lambda data not valid
		//    break;
		case 4: // Warming up, Lambda value is temp in 1/10% of operating temp
			InnovateLC2AFR = AFR_ERROR;
			innovate_o2_sensor[i].warmup = ((ser_buffer[4 + i * 4] << 7 | ser_buffer[5 + i * 4]) & 0x1FFF);
			//catch potential overflow:
			if (innovate_o2_sensor[i].warmup >= 1023) {
				innovate_o2_sensor[i].warmup = 1023;
			} else if (innovate_o2_sensor[i].warmup <= 0) {
				innovate_o2_sensor[i].warmup = 0;
			}	
			break;
			//  case 5: // Heater Calibration, Lambda value contains calibration countdown
			//    break;
		case 6: // Error code in Lambda value
			InnovateLC2AFR = AFR_ERROR;
			innovate_o2_sensor[i].error_code = (sensor_error_code_t)((ser_buffer[4 + i * 4] << 7 | ser_buffer[5 + i * 4]) & 0x1FFF);
			//catch potential overflow:
			if (innovate_o2_sensor[i].error_code >= (sensor_error_code_t)1023) {
				innovate_o2_sensor[i].error_code = (sensor_error_code_t)1023;
			} else if (innovate_o2_sensor[i].error_code <= 0) {
				innovate_o2_sensor[i].error_code = (sensor_error_code_t)0;
			}
			break;
			//  case 7: // reserved
			//    break;
		default:
			InnovateLC2AFR = AFR_ERROR;
			break;
		}
	}
}

void ResetSerialSensor() {
	ClearSerialBuffer();
	ParseSerialData();
}

void ClearSerialBuffer() {
	memset(ser_buffer, 0, sizeof(ser_buffer));
}

void ParseSerialData()  {
	if (engineConfiguration->enableInnovateLC2)
		IdentifyInnovateSerialMsg();
}

#endif