CAN-Skeleton

This is the base project structure for any Arduino code that uses the CAN bus network.

How to use this?

1. Clone the repo.
   1. If you have git in the terminal, run git clone https://github.com/ku-solar-car/canskeleton.git.
   2. Otherwise, click the download code button.
2. Edit the canskeleton.ino file.

Can I rename the .ino file?

Only if you rename the folder to have the same name. So canskeleton.ino needs to be in the canskeleton/ folder.

What are these other files?

The other .cpp and .h files are from a library from the manufacturer. They don't need to be changed. Probably don't change them :)

void setup()

This function is where we do the configuration for the Arduino. This runs once as the startup of the device, so just do one time setup stuff. There is already one canInit block in there that can be used.

Setting up input and output pins

When you need to use a pin, use the pinMode function to configure it.

pinMode(RELAY_PIN, OUTPUT); // Or INPUT for input pins
digitalWrite(RELAY_PIN, HIGH); // Or LOW, write a starting value

void loop()

This is where we put code that will be repeated. This is where you will do the bulk of the work.

How do I send CAN messages?

CAN messages are sent using the canTx function. Most of the code is in a block like this:

byte port = 0; // Or 1
long msgId = 0x700; // Choose an ID that is unique. Anything about 0x700 should be good
byte txData[] = {0x0, 0x1}; // Set the data you want to send
byte length = 2; // Set the length of byte array to send (1-8 bytes per frame)

if (canTx(port, msgId, false, txData, length) == CAN_OK) {
    // Do code that runs if message sent successfully
}

How do I receive CAN messages?

byte port = 0; // Or 1
long msgId; // This will hold the array of the CAN frame
bool extendedFormat; // This will tell if the message ID is long
byte rxData[8]; // Set the data you want to send, with the length
byte length = 8; // Set the length of byte array to send (1-8 bytes per frame)

if (canRx(port, &msgId, &extendedFormat, &rxData[0], &length) == CAN_OK) {
    if (msgId == 0x700) { // Substitute whatever ID you are looking for
        // Do stuff with that CAN frame
    }
}