7 Layer 2 Communication Mode (11/29 bit ID)
7.1 [BFM #100 to #399] Sending/Receiving Pre-defined Layer 2 Messages
61
FX
3U
-J1939 User's Manual
1
Introduc
tion
2
Specifi
cations
3
Inst
allati
on
4
Wi
rin
g
5
Al
lo
ca
tion of
Buf
fer
Memor
ies
6
J1939 C
omms
Mode
7
La
ye
r 2
C
omm
uni
cation
M
ode
8
PL
C RUN>
S
TOP
Me
ssag
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9
Co
mmand
Interface
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Comm
uni
cation
Setti
ngs
Proc
edure
7. Layer 2 Communication Mode (11/29 bit ID)
This chapter describes the data transfer locations and setting of the Layer 2 communication (11/29 bit ID)
mode. In this mode up to 42 predefined messages can be sent/received.
Moreover, Layer 2 messages can be sent via CIF.
In 11 bit ID mode (BFM #21 = K11), the module sends and receives only CAN messages with an 11 bit
identifier. In 29 bit ID mode (BFM #21 = K29), the module sends and receives only CAN messages with a 29
bit identifier.
Note
• To ensure that the FX
3U
-J1939 module can handle the Layer 2 message in a consistent way, it is
necessary to set BFM #20 bit 0 to ON before reading the received message (FROM) and after writing the
transmitted message (TO) to the module.
For BFM #20 bit 0, refer to Section 5.3
• To activate the Layer 2 communication (11/29 bit ID) mode, write into BFM #21 the value K11 or K29, and
reset the module.
For module reset, refer to Section 5.7
• BFMs (#40 to #48, #500 to #973, #1300 to #1799, and #3000 to #3879), which are active in J1939
communication mode, are not active and not accessible.
7.1
[BFM #100 to #399] Sending/Receiving Pre-defined Layer 2 Messages
The data transfer locations of the Layer 2 communication (11/29 bit ID) mode are as follows.
Note
The following settings of each message have to be defined in request configuration mode, before requesting
online mode.
• The CAN-ID LW, CAN-ID HW and transmitting data byte number (in RTR/new/DLC) in the following BFMs
• Layer 2 message configuration in BFM #1100 to #1276
Set the parameters (transmitting/receiving message, etc.) for each message.
For Layer 2 message configuration in BFM #1100 to #1267, refer to the Section 7.2
BFM No.
Name
Description
Message
No.
Initial
Value
Read/
Write
Stored to
Flash ROM
High Byte
Low Byte
BFM #100
CAN-ID 1 LW
*1
11/29 bit CAN-ID low word
La
ye
r 2 mes
sa
ge
1
HFFFF
R/W
*2
BFM #101
CAN-ID 1 HW
*1
11/29 bit CAN-ID high word
HFFFF
R/W
*2
BFM #102
RTR/new/DLC
*1
Status/Control Flags
DLC
H0
R/W
*2
BFM #103
Data bytes
*1
2nd data byte
1st data byte
H0
R/W
-
BFM #104
4th data byte
3rd data byte
H0
R/W
-
BFM #105
6th data byte
5th data byte
H0
R/W
-
BFM #106
8th data byte
7th data byte
H0
R/W
-
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