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ME31-XAAX0440_UserManul_EN
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Exit without saving parameters: Automatically exit the parameter setting interface after 30 seconds without any operation
in the parameter setting interface, and the parameters will not be saved.
4.7 Modbus TCP protocol data frame description
TCP frame format:
Transaction ID
Protocol ID
length
Device address
function code
Data segment
2 Bit
2 Bit
N+2 Bit
1 Bit
1 Bit
N Bit
Transaction processing identifier: It can be understood as the serial number of the message. Generally, 1 is added
after each communication to distinguish different communication data messages.
Protocol identifier: 00 00 means Modbus TCP protocol.
Length: Indicates the length of the next data, in bytes.
For example: get DI status
01 00
00 00
00 06
01
02
00 00 00 04
Transaction ID
Protocol ID
length
Device address
function code
Data segment
4.8 Modbus RTU protocol data frame description
RTU frame format:
Device address
function code
Data segment
Check code CRC
1 Bit
1 Bit
N Bit
2 Bit
For example: Get DI status command
01
02
00 00 00 04
79 C9
Device Modbus address
function code
Data segment
CRC Check code
