Packet structure

+---------------------------+
|      CAN ID and flags     |
|         (4 Octets)        |
+---------------------------+
|    Frame payload length   |
|         (1 Octet)         |
+---------------------------+
|          Padding          |
|         (1 Octet)         |
+---------------------------+
|      Reserved/Padding     |
|         (1 Octet)         |
+---------------------------+
|      Reserved/Padding     |
|         (1 Octet)         |
+---------------------------+
|           Payload         |
.                           .
.                           .
.                           .

Description

The field containing the CAN ID and flags is in network byte order (big-endian). The bottom 29 bits contain the CAN ID of the frame. The remaining bits are:

• 0x20000000 - set if the frame is an error message rather than a data frame.
• 0x40000000 - set if the frame is a remote transmission request frame.
• 0x80000000 - set if the frame is an extended 29-bit frame rather than a standard 11-bit frame. frame.