Table 27, Table 28, Read/write multiple registers 23 (17 h) – Yaskawa V1000-Series Option SI-EM3D/V Dual Port EtherNet Modbus TCP/IP Technical Manual User Manual
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Table 27 Example Write Multiple Registers Response
Description
Data (Hex)
Slave Address
01
Function Code
10
Starting Register
Upper
00
Lower
01
Quantity of Registers
Upper
00
Lower
02
Table 28 Example Write Multiple Registers Error Response
Description
Data (Hex)
Slave Address
01
Error Code
90
Exception Code
02
n
Read/Write Multiple Registers 23 (17 H)
This function code performs a combination of one read operation and one write operation in a single Modbus TCP/IP
transaction. The write operation is performed before the read. The command specifies the starting read address, quantity of
contiguous registers to read, starting write address, quantity of contiguous registers to write and the values to be written. The
normal response contains the values of the registers that were read.
For both the address and the values, the first byte contains the most significant bits and the second byte contains the least
significant bits.
Note:
In option software version VST800380, any invalid register in the range will return an error response.
In option versions VST800381 and later, invalid registers in the range will not return an error response provided at least 1 register is valid.
Invalid registers will be set to 0 in the response.
Table 29 Read/Write Multiple Registers Command
Description
Byte
Data (Hex)
Slave Address
1
00 to FF
Function Code
1
17
Read Starting Register
2
0000 to FFFF
Quantity of Registers to Read
2
M
<1>
Write Starting Register
2
0000 to FFFF
Quantity of Registers to Write
2
N
<2>
Write Byte Count
1
N
<2>
X 2
Write Register Values
N
<2>
X 2
0000 to FFFF
<1> M = Quantity of Registers to Read (range is 1 - 16)
<2> N = Quantity of Registers to Write (range is 1 - 16)
Table 30 Read/Write Multiple Registers Response
Description
Byte
Data (Hex)
Slave Address
1
00 to FF
Function Code
1
17
Number of Data Bytes
1
M
<1>
x 2
Read Register Values
2
Values contained in slave registers
<1> M = Quantity of Registers
Table 31 Read/Write Multiple Registers Error Response
Description
Byte
Data (Hex)
Slave Address
1
00 to FF
Error Code
1
97
Exception Code
1
Refer to Modbus TCP/IP Exception Codes
7 Modbus TCP/IP Messaging
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YASKAWA SIEP YAICOM 17A V1000 Option Dual-Port Modbus TCP/IP SI-EM3D/V Technical Manual