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|
/*************************************************************************
* Arduino Library for OBD-II UART/I2C Adapter
* Distributed under BSD License
* Visit http://freematics.com for more information
* (C)2012-2016 Stanley Huang <stanleyhuangyc@gmail.com>
*************************************************************************/
#include <Arduino.h>
#include <Wire.h>
#include "OBD.h"
//#define DEBUG Serial
uint16_t hex2uint16(const char *p)
{
char c = *p;
uint16_t i = 0;
for (char n = 0; c && n < 4; c = *(++p)) {
if (c >= 'A' && c <= 'F') {
c -= 7;
} else if (c>='a' && c<='f') {
c -= 39;
} else if (c == ' ') {
continue;
} else if (c < '0' || c > '9') {
break;
}
i = (i << 4) | (c & 0xF);
n++;
}
return i;
}
byte hex2uint8(const char *p)
{
byte c1 = *p;
byte c2 = *(p + 1);
if (c1 >= 'A' && c1 <= 'F')
c1 -= 7;
else if (c1 >='a' && c1 <= 'f')
c1 -= 39;
else if (c1 < '0' || c1 > '9')
return 0;
if (c2 >= 'A' && c2 <= 'F')
c2 -= 7;
else if (c2 >= 'a' && c2 <= 'f')
c2 -= 39;
else if (c2 < '0' || c2 > '9')
return 0;
return c1 << 4 | (c2 & 0xf);
}
/*************************************************************************
* OBD-II UART Adapter
*************************************************************************/
byte COBD::sendCommand(const char* cmd, char* buf, byte bufsize, int timeout)
{
write(cmd);
dataIdleLoop();
return receive(buf, bufsize, timeout);
}
void COBD::sendQuery(byte pid)
{
char cmd[8];
sprintf(cmd, "%02X%02X\r", dataMode, pid);
#ifdef DEBUG
debugOutput(cmd);
#endif
write(cmd);
}
bool COBD::readPID(byte pid, int& result)
{
// send a query command
sendQuery(pid);
// receive and parse the response
return getResult(pid, result);
}
byte COBD::readPID(const byte pid[], byte count, int result[])
{
byte results = 0;
for (byte n = 0; n < count; n++) {
if (readPID(pid[n], result[n])) {
results++;
}
}
return results;
}
byte COBD::readDTC(uint16_t codes[], byte maxCodes)
{
/*
Response example:
0: 43 04 01 08 01 09
1: 01 11 01 15 00 00 00
*/
byte codesRead = 0;
for (byte n = 0; n < 6; n++) {
char buffer[128];
sprintf_P(buffer, n == 0 ? PSTR("03\r") : PSTR("03%02X\r"), n);
write(buffer);
if (receive(buffer, sizeof(buffer)) > 0) {
if (!strstr(buffer, "NO DATA")) {
char *p = strstr(buffer, "43");
if (p) {
while (codesRead < maxCodes && *p) {
p += 6;
if (*p == '\r') {
p = strchr(p, ':');
if (!p) break;
p += 2;
}
uint16_t code = hex2uint16(p);
if (code == 0) break;
codes[codesRead++] = code;
}
}
break;
}
}
}
return codesRead;
}
void COBD::clearDTC()
{
char buffer[32];
write("04\r");
receive(buffer, sizeof(buffer));
}
void COBD::write(const char* s)
{
#ifdef DEBUG
DEBUG.print("<<<");
DEBUG.println(s);
#endif
OBDUART.write(s);
}
int COBD::normalizeData(byte pid, char* data)
{
int result;
switch (pid) {
case PID_RPM:
case PID_EVAP_SYS_VAPOR_PRESSURE: // kPa
result = getLargeValue(data) >> 2;
break;
case PID_FUEL_PRESSURE: // kPa
result = getSmallValue(data) * 3;
break;
case PID_COOLANT_TEMP:
case PID_INTAKE_TEMP:
case PID_AMBIENT_TEMP:
case PID_ENGINE_OIL_TEMP:
result = getTemperatureValue(data);
break;
case PID_THROTTLE:
case PID_COMMANDED_EGR:
case PID_COMMANDED_EVAPORATIVE_PURGE:
case PID_FUEL_LEVEL:
case PID_RELATIVE_THROTTLE_POS:
case PID_ABSOLUTE_THROTTLE_POS_B:
case PID_ABSOLUTE_THROTTLE_POS_C:
case PID_ACC_PEDAL_POS_D:
case PID_ACC_PEDAL_POS_E:
case PID_ACC_PEDAL_POS_F:
case PID_COMMANDED_THROTTLE_ACTUATOR:
case PID_ENGINE_LOAD:
case PID_ABSOLUTE_ENGINE_LOAD:
case PID_ETHANOL_FUEL:
case PID_HYBRID_BATTERY_PERCENTAGE:
result = getPercentageValue(data);
break;
case PID_MAF_FLOW: // grams/sec
result = getLargeValue(data) / 100;
break;
case PID_TIMING_ADVANCE:
result = (int)(getSmallValue(data) / 2) - 64;
break;
case PID_DISTANCE: // km
case PID_DISTANCE_WITH_MIL: // km
case PID_TIME_WITH_MIL: // minute
case PID_TIME_SINCE_CODES_CLEARED: // minute
case PID_RUNTIME: // second
case PID_FUEL_RAIL_PRESSURE: // kPa
case PID_ENGINE_REF_TORQUE: // Nm
result = getLargeValue(data);
break;
case PID_CONTROL_MODULE_VOLTAGE: // V
result = getLargeValue(data) / 1000;
break;
case PID_ENGINE_FUEL_RATE: // L/h
result = getLargeValue(data) / 20;
break;
case PID_ENGINE_TORQUE_DEMANDED: // %
case PID_ENGINE_TORQUE_PERCENTAGE: // %
result = (int)getSmallValue(data) - 125;
break;
case PID_SHORT_TERM_FUEL_TRIM_1:
case PID_LONG_TERM_FUEL_TRIM_1:
case PID_SHORT_TERM_FUEL_TRIM_2:
case PID_LONG_TERM_FUEL_TRIM_2:
case PID_EGR_ERROR:
result = ((int)getSmallValue(data) - 128) * 100 / 128;
break;
case PID_FUEL_INJECTION_TIMING:
result = ((int32_t)getLargeValue(data) - 26880) / 128;
break;
case PID_CATALYST_TEMP_B1S1:
case PID_CATALYST_TEMP_B2S1:
case PID_CATALYST_TEMP_B1S2:
case PID_CATALYST_TEMP_B2S2:
result = getLargeValue(data) / 10 - 40;
break;
case PID_AIR_FUEL_EQUIV_RATIO: // 0~200
result = (long)getLargeValue(data) * 200 / 65536;
break;
default:
result = getSmallValue(data);
}
return result;
}
char* COBD::getResponse(byte& pid, char* buffer, byte bufsize)
{
while (receive(buffer, bufsize) > 0) {
char *p = buffer;
while ((p = strstr(p, "41 "))) {
p += 3;
byte curpid = hex2uint8(p);
if (pid == 0) pid = curpid;
if (curpid == pid) {
errors = 0;
p += 2;
if (*p == ' ')
return p + 1;
}
}
}
return 0;
}
bool COBD::getResult(byte& pid, int& result)
{
char buffer[64];
char* data = getResponse(pid, buffer, sizeof(buffer));
if (!data) {
recover();
errors++;
return false;
}
result = normalizeData(pid, data);
return true;
}
void COBD::sleep()
{
char buf[32];
sendCommand("ATLP\r", buf, sizeof(buf));
}
char* COBD::getResultValue(char* buf)
{
char* p = buf;
for (;;) {
if (isdigit(*p) || *p == '-') {
return p;
}
p = strchr(p, '\r');
if (!p) break;
if (*(++p) == '\n') p++;
}
return 0;
}
float COBD::getVoltage()
{
char buf[32];
if (sendCommand("ATRV\r", buf, sizeof(buf)) > 0) {
char* p = getResultValue(buf);
if (p) return atof(p);
}
return 0;
}
bool COBD::getVIN(char* buffer, byte bufsize)
{
if (sendCommand("0902\r", buffer, bufsize)) {
char *p = strstr(buffer, "0: 49 02");
if (p) {
char *q = buffer;
p += 10;
do {
for (++p; *p == ' '; p += 3) {
if (*q = hex2uint8(p + 1)) q++;
}
p = strchr(p, ':');
} while(p);
*q = 0;
return true;
}
}
return false;
}
bool COBD::isValidPID(byte pid)
{
if (pid >= 0x7f)
return true;
pid--;
byte i = pid >> 3;
byte b = 0x80 >> (pid & 0x7);
return pidmap[i] & b;
}
byte COBD::begin()
{
long baudrates[] = {38400, 115200};
byte version = 0;
for (byte n = 0; n < sizeof(baudrates) / sizeof(baudrates[0]) && version == 0; n++) {
OBDUART.begin(baudrates[n]);
version = getVersion();
}
return version;
}
byte COBD::getVersion()
{
byte version = 0;
for (byte n = 0; n < 3; n++) {
char buffer[32];
if (sendCommand("ATI\r", buffer, sizeof(buffer), 200)) {
char *p = strchr(buffer, ' ');
if (p) {
p += 2;
version = (*p - '0') * 10 + (*(p + 2) - '0');
break;
}
}
}
return version;
}
byte COBD::receive(char* buffer, byte bufsize, int timeout)
{
unsigned char n = 0;
unsigned long startTime = millis();
char c = 0;
for (;;) {
if (OBDUART.available()) {
c = OBDUART.read();
if (!buffer) {
n++;
} else if (n < bufsize - 1) {
if (c == '.' && n > 2 && buffer[n - 1] == '.' && buffer[n - 2] == '.') {
// waiting siginal
n = 0;
timeout = OBD_TIMEOUT_LONG;
} else {
if (c == '\r' || c == '\n' || c == ' ') {
if (n == 0 || buffer[n - 1] == '\r' || buffer[n - 1] == '\n') continue;
}
buffer[n++] = c;
}
}
} else {
if (c == '>') {
// prompt char received
break;
}
if (millis() - startTime > timeout) {
// timeout
break;
}
dataIdleLoop();
}
}
if (buffer) {
buffer[n] = 0;
}
#ifdef DEBUG
DEBUG.print(">>>");
DEBUG.println(buffer);
#endif
return n;
}
void COBD::recover()
{
sendCommand("\r", 0, 0);
}
bool COBD::init(OBD_PROTOCOLS protocol)
{
const char *initcmd[] = {"ATZ\r", "ATE0\r", "ATH0\r"};
char buffer[64];
for (unsigned char i = 0; i < sizeof(initcmd) / sizeof(initcmd[0]); i++) {
write(initcmd[i]);
if (receive(buffer, sizeof(buffer), OBD_TIMEOUT_LONG) == 0) {
m_state = OBD_DISCONNECTED;
return false;
}
}
if (protocol != PROTO_AUTO) {
sprintf_P(buffer, PSTR("ATSP%u\r"), protocol);
if (receive(buffer, sizeof(buffer), OBD_TIMEOUT_LONG) == 0 && !strstr(buffer, "OK")) {
m_state = OBD_DISCONNECTED;
return false;
}
}
// load pid map
memset(pidmap, 0, sizeof(pidmap));
bool success = false;
for (byte i = 0; i < 4; i++) {
byte pid = i * 0x20;
sendQuery(pid);
char* data = getResponse(pid, buffer, sizeof(buffer));
if (!data) break;
data--;
for (byte n = 0; n < 4; n++) {
if (data[n * 3] != ' ')
break;
pidmap[i * 4 + n] = hex2uint8(data + n * 3 + 1);
}
success = true;
}
if (success) {
m_state = OBD_CONNECTED;
errors = 0;
}
return success;
}
void COBD::end()
{
m_state = OBD_DISCONNECTED;
OBDUART.end();
}
bool COBD::setBaudRate(unsigned long baudrate)
{
OBDUART.print("ATBR1 ");
OBDUART.print(baudrate);
OBDUART.print('\r');
delay(50);
OBDUART.end();
OBDUART.begin(baudrate);
recover();
return true;
}
bool COBD::memsInit()
{
char buf[16];
return sendCommand("ATTEMP\r", buf, sizeof(buf)) > 0 && !strchr(buf, '?');
}
bool COBD::memsRead(int* acc, int* gyr, int* mag, int* temp)
{
char buf[64];
bool success;
if (acc) {
success = false;
if (sendCommand("ATACL\r", buf, sizeof(buf)) > 0) do {
char* p = getResultValue(buf);
if (!p) break;
acc[0] = atoi(p++);
if (!(p = strchr(p, ','))) break;
acc[1] = atoi(++p);
if (!(p = strchr(p, ','))) break;
acc[2] = atoi(++p);
success = true;
} while (0);
if (!success) return false;
}
if (gyr) {
success = false;
if (sendCommand("ATGYRO\r", buf, sizeof(buf)) > 0) do {
char* p = getResultValue(buf);
if (!p) break;
gyr[0] = atoi(p++);
if (!(p = strchr(p, ','))) break;
gyr[1] = atoi(++p);
if (!(p = strchr(p, ','))) break;
gyr[2] = atoi(++p);
success = true;
} while (0);
if (!success) return false;
}
if (temp) {
success = false;
if (sendCommand("ATTEMP\r", buf, sizeof(buf)) > 0) {
char* p = getResultValue(buf);
if (p) {
*temp = (atoi(p) + 12412) / 34;
success = true;
}
}
if (!success) return false;
}
return true;
}
#ifdef DEBUG
void COBD::debugOutput(const char *s)
{
DEBUG.print('[');
DEBUG.print(millis());
DEBUG.print(']');
DEBUG.print(s);
}
#endif
/*************************************************************************
* OBD-II I2C Adapter
*************************************************************************/
byte COBDI2C::begin()
{
Wire.begin();
#ifdef DEBUG
DEBUG.begin(115200);
#endif
recover();
return getVersion();
}
void COBDI2C::end()
{
m_state = OBD_DISCONNECTED;
}
void COBDI2C::write(const char* s)
{
COMMAND_BLOCK cmdblock = {millis(), CMD_SEND_AT_COMMAND};
Wire.beginTransmission(I2C_ADDR);
Wire.write((byte*)&cmdblock, sizeof(cmdblock));
Wire.write(s);
Wire.endTransmission();
}
bool COBDI2C::sendCommandBlock(byte cmd, uint8_t data, byte* payload, byte payloadBytes)
{
COMMAND_BLOCK cmdblock = {millis(), cmd, data};
Wire.beginTransmission(I2C_ADDR);
bool success = Wire.write((byte*)&cmdblock, sizeof(COMMAND_BLOCK)) == sizeof(COMMAND_BLOCK);
if (payload) Wire.write(payload, payloadBytes);
Wire.endTransmission();
return success;
}
byte COBDI2C::receive(char* buffer, byte bufsize, int timeout)
{
uint32_t start = millis();
byte offset = 0;
do {
Wire.requestFrom((byte)I2C_ADDR, (byte)MAX_PAYLOAD_SIZE, (byte)1);
int c = Wire.read();
if (offset == 0 && c < 0xa) {
// data not ready
dataIdleLoop();
continue;
}
if (buffer) buffer[offset++] = c;
for (byte i = 1; i < MAX_PAYLOAD_SIZE && Wire.available(); i++) {
char c = Wire.read();
if (c == '.' && offset > 2 && buffer[offset - 1] == '.' && buffer[offset - 2] == '.') {
// waiting signal
offset = 0;
timeout = OBD_TIMEOUT_LONG;
} else if (c == 0 || offset == bufsize - 1) {
// string terminator encountered or buffer full
if (buffer) buffer[offset] = 0;
// discard the remaining data
while (Wire.available()) Wire.read();
return offset;
} else {
if (buffer) buffer[offset++] = c;
}
}
} while(millis() - start < timeout);
if (buffer) buffer[offset] = 0;
return 0;
}
void COBDI2C::setQueryPID(byte pid, byte obdPid[])
{
byte n = 0;
for (; n < MAX_PIDS && obdPid[n]; n++) {
if (obdPid[n] == pid)
return;
}
if (n == MAX_PIDS) {
memmove(obdPid, obdPid + 1, sizeof(obdPid[0]) * (MAX_PIDS - 1));
n = MAX_PIDS - 1;
}
obdPid[n] = pid;
}
void COBDI2C::applyQueryPIDs(byte obdPid[])
{
sendCommandBlock(CMD_APPLY_OBD_PIDS, 0, (byte*)obdPid, sizeof(obdPid[0])* MAX_PIDS);
delay(200);
}
void COBDI2C::loadQueryData(PID_INFO obdInfo[])
{
sendCommandBlock(CMD_LOAD_OBD_DATA);
dataIdleLoop();
Wire.requestFrom((byte)I2C_ADDR, (byte)MAX_PAYLOAD_SIZE, (byte)0);
Wire.readBytes((char*)obdInfo, sizeof(obdInfo[0]) * MAX_PIDS);
}
#define MPU6050_I2C_ADDRESS 0x68
#define MPU6050_ACCEL_XOUT_H 0x3B // R
#define MPU6050_ACCEL_XOUT_L 0x3C // R
#define MPU6050_ACCEL_YOUT_H 0x3D // R
#define MPU6050_ACCEL_YOUT_L 0x3E // R
#define MPU6050_ACCEL_ZOUT_H 0x3F // R
#define MPU6050_ACCEL_ZOUT_L 0x40 // R
#define MPU6050_TEMP_OUT_H 0x41 // R
#define MPU6050_TEMP_OUT_L 0x42 // R
#define MPU6050_GYRO_XOUT_H 0x43 // R
#define MPU6050_GYRO_XOUT_L 0x44 // R
#define MPU6050_GYRO_YOUT_H 0x45 // R
#define MPU6050_GYRO_YOUT_L 0x46 // R
#define MPU6050_GYRO_ZOUT_H 0x47 // R
#define MPU6050_GYRO_ZOUT_L 0x48 // R
#define MPU6050_PWR_MGMT_1 0x6B // R/W
#define MPU6050_PWR_MGMT_2 0x6C // R/W
#define MPU6050_WHO_AM_I 0x75 // R
typedef struct
{
uint8_t x_accel_h;
uint8_t x_accel_l;
uint8_t y_accel_h;
uint8_t y_accel_l;
uint8_t z_accel_h;
uint8_t z_accel_l;
uint8_t t_h;
uint8_t t_l;
uint8_t x_gyro_h;
uint8_t x_gyro_l;
uint8_t y_gyro_h;
uint8_t y_gyro_l;
uint8_t z_gyro_h;
uint8_t z_gyro_l;
} MPU6050_READOUT_DATA;
bool COBDI2C::memsInit()
{
// default at power-up:
// Gyro at 250 degrees second
// Acceleration at 2g
// Clock source at internal 8MHz
// The device is in sleep mode.
//
uint8_t c;
bool success;
success = MPU6050_read (MPU6050_WHO_AM_I, &c, 1);
if (!success) return false;
// According to the datasheet, the 'sleep' bit
// should read a '1'. But I read a '0'.
// That bit has to be cleared, since the sensor
// is in sleep mode at power-up. Even if the
// bit reads '0'.
success = MPU6050_read (MPU6050_PWR_MGMT_2, &c, 1);
if (!success) return false;
// Clear the 'sleep' bit to start the sensor.
MPU6050_write_reg (MPU6050_PWR_MGMT_1, 0);
return true;
}
bool COBDI2C::memsRead(int* acc, int* gyr, int* mag, int* temp)
{
bool success;
// Read the raw values.
// Read 14 bytes at once,
// containing acceleration, temperature and gyro.
// With the default settings of the MPU-6050,
// there is no filter enabled, and the values
// are not very stable.
MPU6050_READOUT_DATA accel_t_gyro;
success = MPU6050_read (MPU6050_ACCEL_XOUT_H, (uint8_t *)&accel_t_gyro, sizeof(MPU6050_READOUT_DATA));
if (!success) return false;
if (temp) {
// 340 per degrees Celsius, -512 at 35 degrees.
*temp = ((int)(((uint16_t)accel_t_gyro.t_h << 8) | accel_t_gyro.t_l) + 512) / 34 + 350;
}
if (acc) {
MPU6050_store(acc, accel_t_gyro.x_accel_l, accel_t_gyro.x_accel_h);
MPU6050_store(acc + 1, accel_t_gyro.y_accel_l, accel_t_gyro.y_accel_h);
MPU6050_store(acc + 2, accel_t_gyro.z_accel_l, accel_t_gyro.z_accel_h);
}
if (gyr) {
MPU6050_store(gyr, accel_t_gyro.x_gyro_l, accel_t_gyro.x_gyro_h);
MPU6050_store(gyr + 1, accel_t_gyro.y_gyro_l, accel_t_gyro.y_gyro_h);
MPU6050_store(gyr + 2, accel_t_gyro.z_gyro_l, accel_t_gyro.z_gyro_h);
}
if (mag) {
// no magnetometer
mag[0] = 0;
mag[1] = 0;
mag[2] = 0;
}
return true;
}
void COBDI2C::MPU6050_store(int* pData, uint8_t data_l, uint8_t data_h)
{
uint8_t* ptr = (uint8_t*)pData;
*ptr = data_l;
*(ptr + 1) = data_h;
}
bool COBDI2C::MPU6050_read(int start, uint8_t* buffer, int size)
{
int i, n;
Wire.beginTransmission(MPU6050_I2C_ADDRESS);
Wire.write(start);
Wire.endTransmission(false); // hold the I2C-bus
// Third parameter is true: relase I2C-bus after data is read.
Wire.requestFrom(MPU6050_I2C_ADDRESS, size, true);
while(Wire.available() && i<size)
{
buffer[i++]=Wire.read();
}
return i == size;
}
bool COBDI2C::MPU6050_write(int start, const uint8_t* pData, int size)
{
int n;
Wire.beginTransmission(MPU6050_I2C_ADDRESS);
Wire.write(start); // write the start address
n = Wire.write(pData, size); // write data bytes
if (n != size) return false;
Wire.endTransmission(true); // release the I2C-bus
return true;
}
bool COBDI2C::MPU6050_write_reg(int reg, uint8_t data)
{
return MPU6050_write(reg, &data, 1);
}
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