Yaskawa G7 Modbus Communication - Manual (Page 20)

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Protocol
The parameter access method supported by the G7 drive is a subset of the Modbus
♦
communication protocol, which Yaskawa refers to as
MEMOBUS. The G7 drive supports Modbus functions 3, 6, 8 and 10h. The message format varies depending upon the function code of the
message. For each function code, there is a command message from the master and a response message from the slave. The following sections
review the format of the command and response messages for each function.
Message Functions Supported
The following table lists the Modbus function codes available and their minimum and maximum byte lengths.
Table 2.1 Supported Function Codes
Command Message Response Message (Normal)
Function Code Function
Minimum (bytes) Maximum (bytes) Minimum (bytes) Maximum (bytes)
3h (3 dec) Read Multiple Registers 8 8 7 21
6h (6 dec) Write Single Register 8 8 8 8
8h (8 dec) Loop-Back Test 8 8 8 8
10h (16 dec) Write Multiple Registers 11 25 8 8