Application Guide | iC2-Micro Frequency Converters
6.2 How to Control the Drive
6.2.1 Introduction
This section describes codes which can be used in the function and data fields of a Modbus RTU telegram.
6.2.2 Function Codes Supported by Modbus RTU
Modbus RTU supports use of the following function codes in the function field of a telegram:
Table 57: Function Codes
Function Function code (hex)
Read coils 1
Read holding registers 3
Write single coil 5
Write single register 6
Write multiple coils F
Write multiple registers 10
Get comm. event counter B
Report follower ID 11
Read write multiple registers 17
Table 58: Function Codes
Function Function code Subfunction code Subfunction
1 Restart communication.
2 Return diagnostic register.
10 Clear counters and diagnostic
register.
11 Return bus message count.
12 Return bus communication er-
ror count.
13 Return follower error count.
Diagnostics 8
14 Return follower message
count.
6.2.3 Modbus Exception Codes
For a full explanation of the structure of an exception code response, refer to 6.1.7.4.5 Function Field.
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