CANFDNET-400U
High-performance Four-channel CANFD Bus-to-Ethernet Converter User Manual
©2021 Guangzhou ZLG Microelectronics Technology Corp.,Ltd.
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User Manual
Table 4.28 CAN communication frame mutual conversion format (Modbus mode)
Modbus RTU
frame
CAN
message
CAN message 1
CAN message x
Address field
Frame
information
Frame information
Frame information
Function Code
Frame ID3
0x00
0x00
Data field
Frame ID 2
0x00
0x00
Frame ID1
0x00
0x00
Frame ID0
Address field
Address field
CRC field
Data 1
[Segmentation
protocol usage]
[Segmentation
protocol usage]
Data 2
Function Code
Data field
Data 3
Data field
Data 4
Data 5
Data 6
Data 7
Data 8
Table 4.29 CANFD communication frame mutual conversion format (Modbus mode)
Modbus RTU
frame
CANFD
message
CANFD message
1
CANFD message
x
Address field
Frame
information
Frame information
Frame information
Function Code
Frame ID3
0x00
0x00
Data field
Frame ID 2
0x00
0x00
Frame ID1
0x00
0x00
Frame ID0
Address field
Address field
CRC field
Data 1
[Segmentation
protocol usage]
[Segmentation
protocol usage]
Data 2
Function Code
Data field
Data 3
Data field
Data 4
Data…
Data 62
Data 63
Data 64
The CRC check byte of the Modbus RTU frame is not converted into the CAN
(CANFD) message, and the CAN (CANFD) message does not need to have the check
byte of the serial frame, because the CAN (CANFD) bus itself has an excellent verification
mechanism.
The converted data is the function code and data field of the protocol content of
