ASCII Bidirectional Data Pipe Messages (internal / diagnostic use)
Message type 0xFE – ASCII Bidirectional Data Pipe Send
Header (29 bits) 2 22 11 00 0
8... 43...... 65......87......0
1100011101111 [ A ] [ B ]
3 bits, Priority 6 (110)
2 bits, 00
8 bits, 0xEF
[A] = 8 bits, Target (AB node address | Diagnostic node address)
[B] = 8 bits, Source (Diagnostic node address | AB node address)
Data length – 2 to 8 bytes
Data byte
0 1 2 3 4 5 6 7
bit
7......07......07......07......07......07......07......07......0
11111110 [ A ] [ A ] ...
8 bits, Message type 0xFE
[A] = 8 bits, ASCII character
Example – 18EF80F9 [4] FE 41 42 43
This message from the diagnostic tool at CAN node address ‘0xF9’ sends the 3 ASCII characters ‘ABC’ to the unit at CAN node
address ‘0x80’.
Message type 0xFE – ASCII Bidirectional Data Pipe Ack
Header (29 bits) 2 22 11 00 0
8... 43......65......87......0
1100011101111 [ A ] [ B ]
3 bits, Priority 6 (110)
2 bits, 00
8 bits, 0xEF
[A] = 8 bits, Target Diagnostic node address | AB node address)
[B] = 8 bits, Source (AB node address | Diagnostic node address)
Data length – 1 byte
Data byte
0
bit
7......0
11111110
8 bits, Message type 0xFE
Example – 18EFF980 [1] FE
This response from the unit at CAN node address ‘0x80’ acknowledges the receipt of an ASCII Bidirectional Data Pipe Send from the
diagnostic tool at CAN node address ‘0xF9’.
42
