YASKAWA
SIEP C730600 0IB Modbus TCP/IP Technical Manual
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Table 7.11 Example Read Multiple Registers Error Response
Description
Data (Hex.)
Slave Address (Unit Identifier)
02
Error Code
83
Exception Code
02
06 (06 (Hex.)) Write Single Register
This function code is used to write to a single register in the drive. The command specifies the address of the
register to be written and the value to write. The normal response is an echo of the request, returned after the
register contents have been written.
Table 7.12 Write Single Register Command
Description
Byte No.
Data (Hex.)
Slave Address (Unit Identifier)
1
00 - FF
Function Code
1
06
Register Address
2
0000 - FFFF
Register Values
2
0000 - FFFF
Table 7.13 Write Single Register Response
Description
Byte No.
Data (Hex.)
Slave Address (Unit Identifier)
1
00 - FF
Function Code
1
06
Register Address
2
0000 - FFFF
Register Values
2
0000 - FFFF
Table 7.14 Write Single Register Error Response
Description
Byte No.
Data (Hex.)
Slave Address (Unit Identifier)
1
00 - FF
Error Code
1
86
Exception Code
1
Refer to Modbus TCP/IP Exception Codes.
Examples of Register Write Command
lists command examples when writing register value 0003 (Hex.) to register address 0001 (Hex.) in a
drive with the slave address (unit identifier) 01 (Hex.).
shows examples of responses indicating that the write command has been executed successfully. The
command specifies the value and the register address to write to.
shows examples of an error response when writing to a register. The exception code is 21 (Hex.)
(indicating an invalid value).
Table 7.15 Examples of Register Write Command
Description
Data (Hex.)
Slave Address (Unit Identifier)
01
Function Code
06
Register Address
Upper
00
Lower
01
Register Values
Upper
00
Lower
03
*1
This option is set up to use PLC based (holding) register addressing (base 1). The drive will automatically convert the register
address to one more than the address sent over the network before it will respond.
When writing the register address 0001 (Hex.) from the PLC:
1.
The PLC sends out a command specifying the register address 0000 (Hex.) to the network.
2.
The drive automatically convert the register address 0000 (Hex.) to 0001 (Hex.).
3.
The drive responds the value of register address 0001 (Hex.) to the PLC.