Leonardo Can Bus not recieving data

Other Hardware Device Hacking
1

Hello

I am trying to read my vehicoes CanB with the Leonardo Can Bus Shield Leonardo CAN BUS board.

I have it configured via the 4 pin inputs not the DB9 conector. I have checked the vehices OBD port to confirm the correct readings at CanH and CanL and can see on the meter there is activity on the pins. I have checked at the CanH and CanL inputs on the board when plugged into OBD and im getting signal to the board.

When I try to send data I get message send confirmation however there is no data being read by the board.

I have tried many different librarys and edited my code to suit each but to no avail. I just cant get it to read data.

I have searched here but all similar topics are around code not compiling, my issue is getting it to read data once running.

Can anyone help please?

Excuse the code its a bit messy atm as its been edited 50 times for different librarys, but I can tell why its not working.

#include <Arduino.h>
#include <mcp_can.h>
#include <SPI.h>

#define CANint 2

unsigned char len = 0;
unsigned char buf[8];
unsigned long ID = 0;
unsigned long line = 0;
unsigned long time;

byte data[8] = {0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07};

MCP_CAN CAN0(17); // Set CS to pin 17

void setup() {
  Serial.begin(115200);

  while (!Serial) {
    Serial.print("I will wait here forever...");
    delay(1000);
  };

  pinMode(23, OUTPUT);
  digitalWrite(23, HIGH);

  pinMode(CANint, INPUT);

  Serial.println("CAN init:");

  if (CAN0.begin(CAN_500KBPS) == CAN_OK) {
    Serial.println("Can Init Success");
  } else {
    Serial.println("Can Init Failed");
    while (1) {
      Serial.print("I will wait here forever...");
      delay(1000);
    }
  }

  Serial.println("Good to go!");
}

void loop() {
  time = millis();
  if (CAN_MSGAVAIL == CAN0.checkReceive() && line < 10000) {         // Check to see whether data is read

    digitalWrite(23, LOW);

    if (CAN0.readMsgBuf(&len, buf)) {   // Read data
      ID = CAN0.getCanId();

      line = line + 1;

      Serial.print("ID:");
      Serial.print(ID, HEX); // Output HEX Header
      Serial.print("\t");

      Serial.print("Len:");
      Serial.print(len);
      Serial.print("\t");

      Serial.print("DATA:");
      for (int i = 0; i < len; i++) { // Output 8 Bytes of data in Dec
        Serial.print(buf[i]);
        Serial.print("\t");
      }
      Serial.print("\t");

      Serial.print("time:");
      Serial.print(time); // Timestamp
      Serial.print("\t");

      Serial.print("line:");
      Serial.println(line); // Line Number
    }

    digitalWrite(23, HIGH);
  } else {
    // send data:  ID = 0x100, Standard CAN Frame, Data length = 8 bytes, 'data' = array of data bytes to send
    byte sndStat = CAN0.sendMsgBuf(0x100, 0, 8, data);

    if (sndStat == CAN_OK) {
      Serial.println("Message Sent Successfully!");
    } else {
      Serial.println("Error Sending Message...");
    }
    delay(100);   // send data per 100ms
  }

  delay(10);
}
2

pinMode(23, OUTPUT);
digitalWrite(23, HIGH);

What's that for?
"Pin 23", on a Leonardo?

3

All good, I found my issue, it was hardware related.

pin 23 is and LED

4

13 != 23

5

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.