11
2 Modbus protocol description
2.4 Function codes
Function overview
The functions described in the following (from the Modbus Standard) are available for extract-
ing measured values, device and process data, and for writing data.
Function code Function Limit
Hex. Dec.
03 or 04 3 or 4 Reading n words Max. 127 words (254 bytes)
06 6 Writing one word Max. 1 word (2 bytes)
10 16 Writing n words Max. 127 words (254 bytes)
TIP!
If the device does not respond to these functions (see requirements for communication) or
outputs an error code (see error codes):
The information in Chapter 2.8.1 "Modbus error codes", page 22 may help during trouble-
shooting.
To Next Page
Loading...
Need help?
General
