README.md

Mcp25xxx device family - CAN bus

This binding is currently not finished. Please consider contributing to help us finish it. In the meantime consider using SocketCan

The MCP25XXX is a stand-alone CAN controller and includes features like faster throughput, databyte filtering, and support for time-triggered protocols.

Documentation

• MCP25625 PICtail Plus Daughter Board (ADM00617)
• MCP25625 Mini Can Bus Shield (MCP2515 compatible)
• CAN-BUS Shield
• TotalPhase CAN tools

MCP25XXX devices contain different markings to distinguish features like interfacing, packaging, and temperature ratings. For example, MCP25625 contains a CAN transceiver. Please review specific datasheet for more information.

• MCP2515 datasheet
• MCP25625 datasheet

Usage

You can create a Mcp25625 device like this:

SpiConnectionSettings spiConnectionSettings = new(0, 0);
SpiDevice spiDevice = SpiDevice.Create(spiConnectionSettings);
Mcp25625 mcp25xxx = new Mcp25625(spiDevice);

Read all the registers

You can read all the registers like this:

Console.WriteLine("Read Instruction for All Registers");
Array addresses = Enum.GetValues(typeof(Address));

foreach (Address address in addresses)
{
    byte addressData = mcp25xxx.Read(address);
    Console.WriteLine($"0x{(byte)address:X2} - {address,-10}: 0x{addressData:X2}");
}

to read a single register, just use the Address enum.

RX Status

The RX status is available like this:

Console.WriteLine("Rx Status Instruction");
RxStatusResponse rxStatusResponse = mcp25xxx.RxStatus();
Console.WriteLine($"Value: 0x{rxStatusResponse.ToByte():X2}");
Console.WriteLine($"Filter Match: {rxStatusResponse.FilterMatch}");
Console.WriteLine($"Message Type Received: {rxStatusResponse.MessageTypeReceived}");
Console.WriteLine($"Received Message: {rxStatusResponse.ReceivedMessage}");

Read Status

The Read status is available like this:

Console.WriteLine("Read Status Instruction");
ReadStatusResponse readStatusResponse = mcp25xxx.ReadStatus();
Console.WriteLine($"Value: 0x{readStatusResponse:X2}");
Console.WriteLine($"Rx0If: {readStatusResponse.HasFlag(ReadStatusResponse.Rx0If)}");
Console.WriteLine($"Rx1If: {readStatusResponse.HasFlag(ReadStatusResponse.Rx1If)}");
Console.WriteLine($"Tx0Req: {readStatusResponse.HasFlag(ReadStatusResponse.Tx0Req)}");
Console.WriteLine($"Tx0If: {readStatusResponse.HasFlag(ReadStatusResponse.Tx0If)}");
Console.WriteLine($"Tx0Req: {readStatusResponse.HasFlag(ReadStatusResponse.Tx0Req)}");
Console.WriteLine($"Tx1If: {readStatusResponse.HasFlag(ReadStatusResponse.Tx1If)}");
Console.WriteLine($"Tx1Req: {readStatusResponse.HasFlag(ReadStatusResponse.Tx1Req)}");
Console.WriteLine($"Tx2Req: {readStatusResponse.HasFlag(ReadStatusResponse.Tx2Req)}");
Console.WriteLine($"Tx2If: {readStatusResponse.HasFlag(ReadStatusResponse.Tx2If)}");

Transmit a message

You can transmit a message like this:

Console.WriteLine("Send simple message");
const int id = 1;
var message = new[] { (byte)1 };
var twoByteId = new Tuple<byte, byte>((id >> 3), (id << 5));
mcp25xxx.SendMessage(twoByteId, message);

Read messages from all buffers

You can save all message from buffer to memmory like this:

ConcurrentQueue<byte[]> readBuffer = new();
Console.WriteLine("Start read from buffer mcp25xx buffer to memory buffer");
while (!ct.IsCancellationRequested)
{
    var messages = mcp25xxx.ReadMessages(10);
    foreach (var message in messages)
    {
        readBuffer.Enqueue(message);
    }
}

You can read messaged from memmory like this:

var messageOrNull = readBuffer.TryDequeue(out var bytes) ? bytes : null;

Note: You will find detailed way of using this binding in the sample file

Binding Notes

More details will be added in future PR once core CAN classes/interfaces are determined.