Slave
Function Number
Bytes
Register1 Register0 CRC0
CRC1
1
0x03
4
0x00
0x00
0xFA
0x33
In the event of an error, the slave responds with an error message:
Slave
Errorcode
Exception
CRC0
CRC1
1
0x83
see 8.5
8.4.2 Write Multiple Registers
This function is used to write one or more registers of the slave.
The master first sends a request with the starting address, the number of registers and
the Data to the slave.
Slave
Func.
Start-
adr.1
Start-
adr.0
Number
Reg.1
Number
Reg.0
Number
Bytes
Value
Reg.1
Value
Reg.0
CRC0
CRC1
1
0x10
The request is checked. If all data is correct, the slave responds with the Start address
and the number of written registers.
Slave
Func.
Start-
adr.1
Start-
adr.0
Number
Reg.1
Number
Reg.0
CRC0
CRC1
1
0x10
In the event of an error, the slave responds with an error message:
Slave
Errorcode
Exception
CRC0
CRC1
1
0x90
see 8.5
8.5 Exception Codes
In the event of a faulty inquiry, the slave responds with a Error telegram and one of
the following exception codes. The error code is the function code — 0x80.
0x01 - Illegal function
The Modbus function is not supported.
0x02 - Illegal Data Adress
The register address does not exist. The combination
of start address and number of registers leads to invalid register addresses.
0x03 - Illegal Data Value
The number of registers requested is invalid.
0x04 - Slave Device Failure
The application data itself is invalid.
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