Mitsubishi Electric FX3U-CAN, Руководство пользователя

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9 CAN Layer 2 Mode
9.1 Receive/Transmit Process Data
168
FX
3U
-CAN User's Manual
*1. These BFM will be stored into the Flash ROM when the save command is executed.
→ For the save command, refer to Section 6.6
*2. Receive messages are read only, transmit messages can be read and written.
1. When transmitting messages
The CAN-ID, RTR/new/DLC and data bytes of each message are as follows.
1) CAN-ID
The destination of the message is specified by CAN-ID. CAN-ID is as follows, corresponding to the
function mode to be used.
→
For function mode, refer to Section 6.5
*2. The "n" corresponds to the Layer 2 message number.
2) RTR/new/DLC
RTR/new/DLC is set as follows.
*3. Bit 15 defines whether the message is transmitted as a data frame (Bit 15 = OFF) or a Remote
Transmit Request frame (Bit 15 = ON). Bit 12 = ON enables a strict DLC check for received RTR
frames. If Bit 12 is OFF, only the CAN-ID of an inbound RTR frame is checked for a match with a
user message; if the bit is ON, the CAN-ID and the DLC of the RTR frame must match the user
message to cause a response or BFM #1270 to #1272 flag to be set.
Bit 15 and Bit 12 cannot be set ON at the same time.
Bit 15 can be set ON if the parameter B is set to H5FFF.
Bit 12 can be set ON if the parameter B is set to H6FFF or H7FFF.
→
For parameter B, refer to Section 9.3
3) Data bytes
Store the data to transmit. The data length of the transmit data is set by DLC.
BFM #387 CAN-ID 42 LW 11/29 bit CAN-Identifier low word
Layer 2
message 42
HFFFF R/W
*1
BFM #388 CAN-ID 42 HW 29 bit CAN-Identifier high word HFFFF R/W
*1
BFM #389 RTR / new / DLC
High Byte: Remote Transmission Request
Low Byte: Data length count
H0 R/W
*1
BFM #390
Data bytes
2nd data byte 1st data byte H0
R/W
*2
-
BFM #391 4th data byte 3rd data byte H0
R/W
*2
-
BFM #392 6th data byte 5th data byte H0
R/W
*2
-
BFM #393 8th data byte 7th data byte H0
R/W
*2
-
BFM #394 to #399 Reserved - - -
Function Mode Description
11 bit CAN-ID Layer 2 Mode
Store CAN-ID in the 11 bits, bit 0 to 10, in the CAN-ID n
*2
LW.
In this function mode, CAN-ID n
*2
HW are ignored.
29 bit CAN-ID Layer 2 Mode
Store CAN-ID in the 29 bits, bit 0 to 28, in the CAN-ID n
*2
LW and CAN-ID n
*2
HW.
Handle CAN-ID n
*2
LW and CAN-ID n
*2
HW by 32 bit instructions.
High Byte/Low Byte Description
High byte
Bit 12 ON: Strict DLC check for RTR
Bit 15 OFF: Send data frame
Bit 15 ON: Send RTR frame
*3
Low byte
Number of data bytes to transmit (K0 to K8)
*3
BFM No. Name
Description
Initial
value Read/
Write
Stored to
Flash ROM
High Byte Low Byte