UDP bus transport layer

This chapter defines the UDP bus based transport layer of DroneCAN.

Ports and IP addresses

DroneCAN is carried over UDP using multicast packets. The default multicast IP is 239.65.82.B where B is the DroneCAN bus number, where 0 is used for the first system bus.

The default multicast port is 57732.

Packet format

The packet format is:

   - MAGIC 0x2934 16 bit
   - 16 bit CRC CRC-16-CCITT (over all bytes after CRC)
   - 16 bit flags
   - 32 bit message ID
   - data[]

All data is little endian.

URIs

In tools where the transport is enumerated the URI is “mcast:B” where B is the bus number. This means “mcast:0” is 239.65.82.0 on UDP port 57732.