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Quickstart

Create a Messenger​

require 'can_messenger'

messenger = CanMessenger::Messenger.new(interface_name: 'can0')

Send a Standard CAN Frame​

messenger.send_can_message(id: 0x123, data: [0xDE, 0xAD, 0xBE, 0xEF])

Send an Extended-ID Frame​

messenger.send_can_message(
  id: 0x123456,
  data: [0x01, 0x02, 0x03],
  extended_id: true
)

Send CAN FD​

Enable globally on the messenger:

fd_messenger = CanMessenger::Messenger.new(interface_name: 'can0', can_fd: true)
fd_messenger.send_can_message(id: 0x200, data: Array.new(12, 0xAA))

Or per call:

messenger.send_can_message(id: 0x200, data: Array.new(12, 0xAA), can_fd: true)

Listen for Frames​

listener = Thread.new do
  messenger.start_listening do |msg|
    puts "id=0x#{msg[:id].to_s(16)} extended=#{msg[:extended]} data=#{msg[:data].inspect}"
  end
end

sleep 2
messenger.stop_listening
listener.join

Apply ID Filters​

# One ID
messenger.start_listening(filter: 0x123) { |msg| p msg }

# Range
messenger.start_listening(filter: 0x100..0x1FF) { |msg| p msg }

# Explicit set
messenger.start_listening(filter: [0x120, 0x121, 0x220]) { |msg| p msg }

DBC-assisted Send/Receive​

dbc = CanMessenger::DBC.load('vehicle.dbc')

messenger.send_dbc_message(
  dbc: dbc,
  message_name: 'EngineData',
  signals: { RPM: 2200, Temp: 84 }
)

messenger.start_listening(dbc: dbc) do |msg|
  p msg[:decoded] if msg[:decoded]
end

If EngineData is defined in the DBC with an extended CAN ID, send_dbc_message automatically sends it as an extended frame and the receive path decodes the extended frame back through the same DBC message definition.