Simple test¶
Ensure your device works with this simple test.
1# SPDX-FileCopyrightText: Copyright (c) 2020 Bryan Siepert for Adafruit Industries
2#
3# SPDX-License-Identifier: MIT
4from time import sleep
5import board
6import busio
7from digitalio import DigitalInOut
8from adafruit_mcp2515.canio import Message, RemoteTransmissionRequest
9from adafruit_mcp2515 import MCP2515 as CAN
10
11
12cs = DigitalInOut(board.D5)
13cs.switch_to_output()
14spi = busio.SPI(board.SCK, board.MOSI, board.MISO)
15
16can_bus = CAN(
17 spi, cs, loopback=True, silent=True
18) # use loopback to test without another device
19while True:
20 with can_bus.listen(timeout=1.0) as listener:
21
22 message = Message(id=0x1234ABCD, data=b"adafruit", extended=True)
23 send_success = can_bus.send(message)
24 print("Send success:", send_success)
25 message_count = listener.in_waiting()
26 print(message_count, "messages available")
27 for _i in range(message_count):
28 msg = listener.receive()
29 print("Message from ", hex(msg.id))
30 if isinstance(msg, Message):
31 print("message data:", msg.data)
32 if isinstance(msg, RemoteTransmissionRequest):
33 print("RTR length:", msg.length)
34 sleep(1)