Supplement operating manual for DREHMO i-Matic actuators with integrated
MODBUS fieldbus interface
Wenden, 21.03.12
Page 4 of 18
Prepared by: Ste
2.2 Supported function codes
Among the list of possible modbus functions as described in the modbus guidelines, the following function
codes are supported:
FC 01
Read Coil Status
read single bit of master output data (command check)
FC 02
Read Input Status
read single bit as input to master (bit feedback)
FC 03
Read Holding Registers
read back of master output data as integer (command check)
FC 04
Read Input Registers
read data as input to master (word feedback)
FC 05
Force Single Coil
write single bit of master output data (command)
FC 06
Preset Single Register
write single data of master output data (command)
FC 15
Force Multiple Coils
write multiple bit of master output data (commands)
FC 16
Preset Multiple Registers
write multiple data of master output data (commands)
FC 17
Report Slave ID
Read TAG/KKS
2.3 Data model
The discrete single bit command and status bits for the actuator are mapped in a linear addressable structure.
Each command or status bit can be accessed individually. The commands are also addressable as single or
multiple words.
The reserved addresses for input and output data are as follows:
Coil addresses: range 1 (Hex 0x01 to 512 (Hex 0x200) results in 512 coils reserved
Register addresses: range 513 (Hex 0x201) to 544 (Hex 0x220) results in 32 registers reserved
