Loopback test (08h), Write in several holding registers (10h) – Yaskawa iQpump Controller Programming Manual User Manual
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102
YASKAWA
TM.iQp.07 iQpump Controller Programming Manual
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Loopback Test (08H)
The loopback test returns the command message directly as the response message without changing the contents to check the
communications between the master and slave. Set user-defined test code and data values.
The following tables show a message example when performing a loopback test with the slave 1 drive.
Figure 93. Function Code 08H Message Example
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Write In Several Holding Registers (10H)
Write the specified data to the desired slave indicating the desired starting register. The written data must be consecutive, starting from
the specified address in the command message: High Byte (8 bits), then Low Byte 8 bits, in sequential storage register order.
The following tables show an example of a message when a forward Run command has been set at a speed command of 60.0 Hz in the
slave 1 iQpump drive by the PLC.
Figure 94. Function Code 08H Message Example
Important: Set the number of bytes as quantity of specified registers x 2. Handle response messages in the same way.
Command Message
Response Message
(During Normal Operation)
Response Message
(During Error)
Slave address
01H
Slave address
01H
Slave address
01H
Function code
08H
Function code
08H
Function code
88H
Test Code
High
Byte
00H
Test Code
High
Byte
00H
Error Code
01H
Low
Byte
00H
Low
Byte
00H
CRC-16
High
Byte
86H
Data
High
Byte
A5H
Data
High
Byte
A5H
Low
Byte
50H
Low
Byte
37H
Low
Byte
37H
CRC-16
High
Byte
DAH
CRC-16
High
Byte
DAH
Low
Byte
8DH
Low
Byte
8DH
Command Message
Response Message
(During Normal Operation)
Response Message
(During Error)
Slave Address
01H
Slave Address
01H
Slave Address
01H
Function Code
10H
Function Code
10H
Function Code
90H
Start
Register
High
Byte
00H
Start
Register
High
Byte
00H
Error code
02H
Low
Byte
01H
Low
Byte
01H
CRC-16
High
Byte
CDH
No. of
Registers
High
Byte
00H
No. of
Registers
High
Byte
00H
Low
Byte
C1H
Low
Byte
02H
Low
Byte
02H
No. of Bytes*
04H
CRC-16
High
Byte
10H
First
2 Bytes
of data
High
Byte
00H
Low
Byte
08H
Low
Byte
01H
Second
2 Bytes
of data
High
Byte
02H
* No. of bytes = 2 x (# of Registers)
Low
Byte
58H
CRC-16
High
Byte
63H
Low
Byte
39H