ECUMaster EMU CAN Stream Reader Arduino Library
It reads the EMU CAN Stream and decodes it into something useful.
This works with any CAN enabled device, MCP2515, Teensy, ESP32, STM32, Arduino UNO R4 and more.
Content:
To install EMUcan into your Arduino IDE you can use the Library Manager (available from Arduino IDE version 1.6.2). Open the IDE and click to the Sketch menu and then Include Library → Manage Libraries. There search for "EMUcan" and click Install.
Or alternatively install it as ZIP file:
Download the zip file from our repository and select in Arduino IDE Sketch → Include library → Add .ZIP library....
Or clone it into your Documents/Arduino/libraries folder:
git clone https://github.com/designer2k2/EMUcan.gitWhen installed you will also see a few examples in File → Examples → EMUcan menu.
In the EMU Black, set the CAN-Bus speed to 500 Kpbs and enable "Send EMU stream over CAN-Bus".
The CAN-Bus speed can be modified, see in the examples on how to do it depending on the hardware.
The EMU Stream base ID can be changed, the begin function takes this as parameter.
Wire up the Arduino/Teensy/ESP32/.. to the CAN Bus.
For the MCP2515: https://github.com/autowp/arduino-mcp2515#can-shield
For ESP32 / Teensy: Tested CAN Bus Transceiver can be found here: https://github.com/PaulStoffregen/FlexCAN
For the Arduino UNO R4 see the official Documentation: https://docs.arduino.cc/tutorials/uno-r4-wifi/can
To start the library with EMU Can Base (600 by default)
EMUcan emucan(0x600);You need to set up the receiving of CAN frames, see in the examples on how to to that. And then hand over the important parts to the EMUcan library.
Call this for every received CAN frame:
emucan.checkEMUcan(can_id, can_dlc, data);Where the can_id is the ID from the message. can_dlc is the data length and data the actual data.
For the MCP2515 this could look like:
if (mcp2515.readMessage(&canMsg) == MCP2515::ERROR_OK) {
emucan.checkEMUcan(canMsg.can_id, canMsg.can_dlc, canMsg.data);
}Example on how to read a value:
Serial.println(emucan.emu_data.RPM);All the values:
see https://github.com/designer2k2/EMUcan/blob/main/src/EMUcan.h
// Available data
struct emu_data_t {
uint16_t RPM; //RPM
uint16_t MAP; //kPa
uint8_t TPS; //%
int8_t IAT; //C
float Batt; //V
float IgnAngle; //deg
float pulseWidth; //ms
uint16_t Egt1; //C
uint16_t Egt2; //C
float dwellTime; //ms
int8_t gear; //
uint8_t Baro; //kPa
float analogIn1; //V
float analogIn2; //V
float analogIn3; //V
float analogIn4; //V
float analogIn5; //V
float analogIn6; //V
int8_t emuTemp; //C
float oilPressure; //Bar
uint8_t oilTemperature; //C
float fuelPressure; //Bar
int16_t CLT; //C
float flexFuelEthanolContent; //%
float wboLambda; //λ
uint16_t vssSpeed; //km/h
float lambdaTarget; //λ
uint16_t cel; //
float LambdaCorrection; //%
uint8_t flags1; //Flags 1
uint8_t outflags1; //Outflags 1
uint8_t outflags2; //Outflags 2
uint8_t outflags3; //Outflags 3
uint8_t outflags4; //Outflags 4
uint8_t pwm1; //%
uint16_t boostTarget; //kPa
uint8_t pwm2; //%
float fuel_used; //L
uint8_t DSGmode; //DSG mode
float DBWpos; //%
float DBWtarget; //%
uint16_t TCdrpmRaw; //
uint16_t TCdrpm; //
uint8_t TCtorqueReduction; //%
uint8_t PitLimitTorqueReduction; //%
};Example on how to check if the Engine is currently in idle:
if (emucan.emu_data.flags1 & emucan.F_IDLE) {
Serial.println("Engine Idle active");
}The flags1 would contain following states:
enum FLAGS1 : uint8_t {
F_GEARCUT = (1 << 0), //1 - Gearcut active
F_ALS = (1 << 1), //1 - ALS active
F_LC = (1 << 2), //1 - Launch control active
F_IDLE = (1 << 3), //1 - Is in idle state
F_TABLE_SET = (1 << 4), //0 - table set 1, 1 - table set 2
F_TC_INTERVENTION = (1 << 5), //1 - traction control intervention
F_PIT_LIMITER = (1 << 6), //1 - Pit limiter active
F_BRAKE_SWITCH = (1 << 7) //1 - Brake switch active
};There are many more registers, take a look at https://github.com/designer2k2/EMUcan/blob/main/src/EMUcan.h
The information if the CEL is on can be checked by a dedicated function:
if (emucan.decodeCel()){
Serial.println("WARNING Engine CEL active");
}Details on why the CEL is on is contained in the cel flag:
enum ERRORFLAG : uint16_t {
ERR_CLT = (1 << 0), //Coolant temperature sensor failed
ERR_IAT = (1 << 1), //IAT sensor failed
ERR_MAP = (1 << 2), //MAP sensor failed
ERR_WBO = (1 << 3), //Wide band oxygen sensor failed
ERR_EGT1 = (1 << 4), //EGT sensor #1 failed
ERR_EGT2 = (1 << 5), //EGT sensor #2 failed
EGT_ALARM = (1 << 6), //EGT too high
KNOCKING = (1 << 7), //Knock detected
FFSENSOR = (1 << 8), //Flex Fuel sensor failed
ERR_DBW = (1 << 9), //Drive by wire failure
ERR_FPR = (1 << 10) //Fuel pressure relative error
};Example to check CEL against the ERR_CLT:
if (emucan.emu_data.cel & emucan.ERR_CLT) {
Serial.println("WARNING Engine CEL active due to CLT");
}The EMUcan library provides its status:
enum EMUcan_STATUS {
EMUcan_FRESH,
EMUcan_RECEIVED_WITHIN_LAST_SECOND,
EMUcan_RECEIVED_NOTHING_WITHIN_LAST_SECOND,
};Reading the status:
if (emucan.EMUcan_Status() == EMUcan_RECEIVED_WITHIN_LAST_SECOND) {
Serial.println("Data from EMU received");
} else {
Serial.println("No communication from EMU");
}This Library is tested on Arduino Nano with a MCP2515 shield at 8Mhz.
Further on a Teensy4, Teensy3 and ESP32 with SN65HVD232 transceiver.
The EMU Black was running Software Version 2.154.
For using the ECUMaster serial stream instead of the CAN Bus use this library: https://github.com/GTO2013/EMUSerial
before Version 2, or in the EMUcanT4, the CAN Bus handling was part of the EMUcan lib. Now from Version 2 onwards you have to basically set this up by yourself and handover the CAN frame into the EMUcan library.
This gives you full control over the CAN interface, it also enables this library to be run on basically every hardware.
Please see in the examples on how to make this happen on MCP2515, Teensy and ESP32.
Please feel free to use/extend/report bugs/request features!