Application note - CANbus on fitlet2 with FC-SCG running Linux

• This application note applies to fitlet2 with FC-SCG FACET-Card running Linux
• It provides an example of how to use the CANbus feature of FC-SCG under Linux
• The following application is required for the CAN bus functionality: fitlet2 FTDI CAN sniffer

Simple CAN bus sniffer

Written for the following chain: FTDI232H <-> MCP2515.
Tested on Linux 4.14.41 (Debian sid)

Prerequisites: libmpsse-1.3

libftdi1-1.4 via https://www.intra2net.com/en/developer/libftdi/repository.php
libusb-1.0   via https://libusb.info/

Avaliable binaries:

sniff -- dynamically linked against mentioned libraries
sniff.static -- statically linked executable

Usage:

Prints received frames to STDOUT, sends to net frames gotten from STDIN. Options:

       --can_bitrate Hz        required CAN bus speed
       --can_osc Hz            CAN clock oscillator frequency in fact

decimal modifiers 'k' and 'M' are allowed

       --promiscuous [01]      a given RX buffer is to receive all frames
       --rollover              rollover mode for RX buffer 0
       --mask [01]:sid-eid     acceptance mask for a mentioned RX buffer
       --filter [012345]:sid-eid       acceptance filter

filters 0 and 1 are purposed for RX buffer 0 and the others for RX buffer 1

       mask and filters format: n:sid-eid
       where:
       num     number of mask or filter
       sid     Standard identifier of mask/filter
       eid     enhanced identifier of mask/filter

Omitted eid (if any) will be zeroed.

       --sniff                 listen-only mode
       --showraw               print out frames received/to be sent in hex

Allowed frame to be sent format:

sid:paiload[0...i]
sid-eid:paiload[0...i]

• where "i" must be less than 8

For more detailed explanation of the mentioned options please read the MCP2515 datasheet:
MCP2515 CAN bus interface chip datasheet