This repository provides CAN ID definitions for the Yale Bulldog Racing team, intended for use as a Teensy 4.1 library.

bdr-can-ids repository manual

About this library

This is the documentation for the Github repository called bdr-can-ids. It enables easy access to the motor inverter’s can id communication protocol, which is proprietary, and thus, arbitrary. Thus, ease of access is achieved through the existence of this github repository, in the form of an Arduino library.

Who should use this library?

People who are using Teensy/other Arduino-based systems can use this library.

Hardware requirements

• Teensy 4.01

recognized hardware:

• Motor Inverter (from DTI)

• orion2 bms

Quickstart

1. Navigate to the repository page on Github bdr-can-ids

2. Download as .zip file

3. Open Arduino IDE

4. Add library as zip (on MacOS sketch -> include library -> add .ZIP library…)

usage

structs

each id is given a CanMessage construct, to store the kind of message each id is. it looks like this:

    struct CanMessage {
        const char* name;           // main name
        uint32_t id;                // CAN ID
        const char* alt;            // alternative name
        const char* byte;           // byte
        int bit_start;              // start bit
        int length;                 // length
        float min;                  // minimum value
        float max;                  // maximum value
        float scale;                // value multiplier
        const char* units;          // display units
        const char* description;    // a long string description
    };

here additionally is the message struct. it contains a can message

struct messageStruct {
        uint32_t id;
        uint8_t data[8];
        uint8_t length;
    };

functions

there are several basic functions this library has:

important functions

createMessageInv

messageStruct createMessageInv(uint32_t id, const uint8_t* data, uint8_t length);

creates an inverter message.

sendOBD2Request

void sendOBD2Request(uint16_t pid);

sends an OBD2 request. the orion2 bms uses a specific type of can, and waits for a message request before sending any kind of can message, unless manually configured otherwise

interpretInverterMessage

float interpretInverterMessage(const messageStruct& msg, const CanMessage& definition);

Interprets a raw CAN message from the motor inverter and extracts the scaled value according to the message definition. Returns the interpreted value as a float.

interpretBMSMessage

float interpretBMSMessage(const messageStruct& msg, const CanMessage& definition);

Interprets a raw CAN message from the Orion BMS and extracts the scaled value according to the message definition. Uses big-endian byte ordering typical of BMS systems. Returns the interpreted value as a float.

findMessageByID

static const CanMessage* findMessageByID(uint32_t id);

Finds and returns a pointer to the CanMessage definition for a given CAN ID. Returns nullptr if the ID is not recognized. Useful for automatic message interpretation.

isInverterMessage

static bool isInverterMessage(const CanMessage* msg);

Helper function that returns true if the message definition is from the motor inverter (ID range 0x01-0xFF).

isBMSMessage

static bool isBMSMessage(const CanMessage* msg);

Helper function that returns true if the message definition is from the BMS (ID range 0xF000+).

other functions

getAllCANIDs

static uint32_t* getAllCANIDs(int* count = nullptr);

gets an array of every id (for display purposes). Optionally returns the count of IDs through the count pointer parameter.

conv_to_dec

static float conv_to_dec(const String& s);

converts a string number with decimals separated by commas into floats separated by periods, ie "1,32" -> 1.32 In the motor inverter documentation, it is common to find these kinds of numbers.

usage example

#include <bdrcanlib.h>

BDRCANLib canLib;

void setup() {
    Serial.begin(115200);
    // Initialize CAN bus here
}

void loop() {
    // Receive a CAN message (example)
    messageStruct receivedMsg;
    // ... (populate receivedMsg from CAN bus)
    
    // Find the message definition
    const CanMessage* msgDef = BDRCANLib::findMessageByID(receivedMsg.id);
    
    if (msgDef != nullptr) {
        float value;
        
        // Interpret based on message type using helper functions
        if (BDRCANLib::isInverterMessage(msgDef)) {
            value = canLib.interpretInverterMessage(receivedMsg, *msgDef);
        } else if (BDRCANLib::isBMSMessage(msgDef)) {
            value = canLib.interpretBMSMessage(receivedMsg, *msgDef);
        } else {
            // other message type
            return;
        }
        
        Serial.print(msgDef->name);
        Serial.print(": ");
        Serial.print(value);
        Serial.print(" ");
        Serial.println(msgDef->units);
    }
}

ids:

here is a list of recognised id messages that this library can use:

dti motor inverter:

Command Messages:

• Set_AC_Current
• Set_Brake_Current
• Set_ERPM
• Set_Position
• Set_Relative_Current
• Set_Relative_Brake_Current
• Set_Digital_Output_1
• Set_Digital_Output_2
• Set_Digital_Output_3
• Set_Digital_Output_4
• Max_AC_Current
• Set_Maximum_AC_Brake_Current
• Max_DC_Current
• Set_Maximum_DC_Brake_Current
• Drive_Enable

Feedback/Status Messages:

• erpm
• duty_cycle
• input_voltage
• AC_current
• DC_current
• RESERVED_1
• controller_temperature
• motor_temperature
• fault_code
• RESERVED_2
• Id
• Iq
• throttle_signal
• brake_signal
• digital_input_1
• digital_input_2
• digital_input_3
• digital_input_4
• digital_input_1_2
• digital_input_2_2
• digital_input_3_2
• digital_input_4_2
• drive_enable
• capacitor_temp_limit
• DC_current_limit
• drive_enable_limit
• igbt_acceleration_temperature_limit
• igbt_temperature_limit
• input_voltage_limit
• motor_acceleration_temperature_limit
• motor_temperature_limit
• RPM_min_limit
• RPM_max_limit
• power_limit
• reserved_3
• reserved_4
• CAN_map_version

orion2 bms

General BMS Messages:

• relays_status
• max_cells_supported_count
• populated_cell_count
• pack_charge_current_limit
• pack_discharge_current_limit
• signed_pack_current
• unsigned_pack_current
• pack_voltage
• pack_open_voltage
• pack_state_of_charge
• pack_amphours
• pack_resistance
• pack_depth_of_discharge
• pack_health
• pack_summed_voltage
• total_pack_cycles
• highest_pack_temperature
• lowest_pack_temperature
• avg_pack_temperature
• heatsink_temperature_sensor
• fan_speed
• requested_fan_speed
• low_cell_voltage
• low_cell_voltage_id
• high_cell_voltage
• high_cell_voltage_id
• avg_cell_voltage
• low_opencell_voltage
• low_opencell_voltage_id
• high_opencell_voltage
• high_opencell_voltage_id
• avg_opencell_voltage
• low_cell_resistance
• low_cell_resistance_id
• high_cell_resistance
• high_cell_resistance_id
• avg_cell_resistance
• input_power_supply_voltage
• fan_voltage

Cell Voltage Arrays (15 messages for cells 1-180):

• cell_voltages_1_12
• cell_voltages_13_24
• cell_voltages_25_36
• cell_voltages_37_48
• cell_voltages_49_60
• cell_voltages_61_72
• cell_voltages_73_84
• cell_voltages_85_96
• cell_voltages_97_108
• cell_voltages_109_120
• cell_voltages_121_132
• cell_voltages_133_144
• cell_voltages_145_156
• cell_voltages_157_168
• cell_voltages_169_180

Opencell Voltage Arrays (15 messages for cells 1-180):

• opencell_voltages_1_12
• opencell_voltages_13_24
• opencell_voltages_25_36
• opencell_voltages_37_48
• opencell_voltages_49_60
• opencell_voltages_61_72
• opencell_voltages_73_84
• opencell_voltages_85_96
• opencell_voltages_97_108
• opencell_voltages_109_120
• opencell_voltages_121_132
• opencell_voltages_133_144
• opencell_voltages_145_156
• opencell_voltages_157_168
• opencell_voltages_169_180

Internal Resistance Arrays (15 messages for cells 1-180):

• internal_resistances_1_12
• internal_resistances_13_24
• internal_resistances_25_36
• internal_resistances_37_48
• internal_resistances_49_60
• internal_resistances_61_72
• internal_resistances_73_84
• internal_resistances_85_96
• internal_resistances_97_108
• internal_resistances_109_120
• internal_resistances_121_132
• internal_resistances_133_144
• internal_resistances_145_156
• internal_resistances_157_168
• internal_resistances_169_180

Source

DTI motor inverter can manual orion2 BMS can PID sheet and documentation

All the IDs and other related information were taken from this manual, compiled in a spreadsheet, exported as CSV, then auto-formatted (through a Python script of my own design) into a library.