IDEC FC6A-C16K1CE Communications Manual page 170

8: J1939 C
OMMUNICATION
Device Address
Addresses are defined between 0 and 255.
However, 254 (null address) is the result of an address conflict and is only used when an address cannot be obtained. 255 (global
address) is used when broadcasting messages to all CAs without specifying a specific CA.
Address
0 to 253 Address range allocated to CAs
254 Null address
255 Global address
NAME (64 bits total)
The 64-bit NAME is split into multiple fields. The content for a portion of the fields is already defined in the standard. NAME must
be set to a value that is not duplicated by another device on the same J1939 communication network. For details on the definition
of each bit, refer to the SAE J1939 standard.
Field Name
Arbitrary Address Capable
Industry Group
Vehicle System Instance
Vehicle System
Reserved
Function
Function Instance
ECU Instance
Manufacturer Code
Identify Number
*1 "Yes" items are defined in the standard. Set those items according to the used network and purpose.
The CAN J1939 All-in-One Type resolves address conflicts with CAs according to the value of the Arbitrary Address Capable bit.
If the Arbitrary Address Capable bit is 0
The CAN J1939 All-in-One Type operates as a fixed address CA. If there is a CA that has the same address as the local address,
the CAN J1939 All-in-One Type can exchange messages with the set local address if its priority is high.
If the CAN J1939 All-in-One Type priority is low, the local address is 254 (null address).
If the Arbitrary Address Capable bit is 1
The CAN J1939 All-in-One Type operates as a dynamic address CA. If there are CAs that duplicate the local address, the local
address is compared to that of the corresponding CA, and if the CAN J1939 All-in-One Type priority is lower, it repeatedly
attempts to acquire another address. When the local address has been determined, messages can be exchanged.
If the local address was not determined by the last address, it is set to 254 (null address).
PGN
CAs exchange parameter information such as the engine RPM and the on/off status of switches. These parameters are defined in
advance and assigned unique ID numbers (SPNs). The parameters are also grouped according to content, and these parameter
groups are assigned unique ID numbers (PGN).
CAs exchange messages for each PGN.
Example: SPNs that make up PGN 1792 General Purpose Valve Pressure
SPN
4086 Valve Load Sense Pressure
4087 Valve Pilot Pressure
4088 Valve Assembly Load sense Pressure
4089 Valve Assembly Supply Pressure
*1 From J1939-71
8-2
Description
For a portion of addresses, the use has been determined according to the type of
connected device. For details, refer to the SAE J1939 standard.
Set as the result of an address conflict when an address between 0 and 253 could not be
obtained.
Used when transmitting a message as a broadcast.
Bit Length
1 (high order)
3
4
7
1
8
5
3
11
21 (low order)
FC6A S M S A
ERIES ICRO MART
*1
SAE Defined
— Dynamic address support
Yes Industry group
— Vehicle system instance
Yes Vehicle system
Yes Reserved (fixed as 0)
Yes Function
— Function instance
— ECU instance
Yes Manufacturer code
— ID number
*1
Parameter Name
- -O T C
LL IN NE YPE OMMUNICATION
Details
Item
M FC9Y-B1730
ANUAL
Data Size
2 bytes
1 byte
2 bytes
2 bytes