IDEC FC6A-C16K1CE Communications Manual page 171

Message
CAs use the data frame in the CAN extended frame format that holds the 29-bit CAN ID to exchange messages. The CAN ID is
composed of the priority, PGN, and source address. The PGN is composed of the EDP, DP, PDU Format (PDUF), and PDU Specific
(PDUS).
Message
S 29 Bits R 6 Bits
O T
CAN ID Control
F R
3 Bits 18 Bits
Priority PGN
1 Bit 1 Bit
EDP DP
PDU 1 format
When PDUF is 00h to EFh, the PGN is defined in the format called the PDU1 format. The PGN is defined with EDP, DP, and
PDUF, and it is handled as a PGN for one-to-one communication. At this time, the destination address is stored in the PDUS.
However, when the PDUS is specified as 255 (global address), the PGN is handled as a broadcast PGN, not as one-to-one
communication.
PDU 2 format
When PDUF is F0h to FFh, the PGN is defined in the format called the PDU2 format. The PGN is defined with EDP, DP, PDUF,
and PDUS, and it is handled as a PGN for broadcast communication.
Since the data that can be stored in the CAN data frame is a maximum of 8 bytes, when the PGN data is 9 bytes or longer,
messages are split into 8-byte packets and exchanged as multi-packet messages.
Overview of J1939 Communication Supported by the CAN J1939 All-in-One Type
The CAN J1939 All-in-One Type can connect to a J1939 communication network as an ECU that has one CA. It is compatible with
the network management function that manages addresses between CAs so address conflicts can be resolved and dynamic
addresses can be assigned.
CAN Port
FC6A Series MicroSmart
(CAN J1939 All-in-One Type) (ECU)
8 Bytes 16 Bits
Data CRC
8 Bits
Source Address
8 Bits 8 Bits
PDU Format PDU Specific
CAN
CA
FC6A S M S A
ERIES ICRO MART LL
2 Bits 7 Bits
ACK EOF
ECU
CA CA
- -O T C
IN NE YPE OMMUNICATION
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