Yaskawa iQpump Controller Programming Manual User Manual
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YASKAWA
TM.iQp.07 iQpump Controller Programming Manual
Function Code
The function code specifies commands. There are four function codes supported by the drive, as shown below.
Table 36 MEMOBUS / Modbus Function Codes
Data
Configure consecutive data by combining the storage register address (test code for a loopback address) and the data the register contains.
The data length changes depending on the command details.
Error Check
Errors are detected during communication using CRC-16. Perform calculations using the following method:
1. The factory setting for CRC-16 communication is typically zero, but when using the MEMOBUS / Modbus system, set the factory
setting to one (e.g., set all 16 bits to 1).
2. Calculate CRC-16 using MSB as slave address LSB, and LSB as the MSB of the final data.
3. Calculate CRC-16 for response messages from the slaves and compare them to the CRC-16 in the response messages.
Function Code
(Hexadecimal)
Function
Command Message
Response Message
Min. (Bytes)
Max. (Bytes)
Min.* (Bytes)
Max. (Bytes)
03H
Reading / Holding Register Contents
8
8
7
37
06H
Write In Single Holding Register
8
8
8
8
08H
Loopback Test
8
8
8
8
10H
Write In Several Holding Registers
11
41
8
8
* Minimum bytes for a normal Response Message (error response message is always 5 bytes).