3 function codes (client connections), Function codes (client connections) – Pilz PSSnet GW1 MOD-EtherCAT User Manual
Page 18
Function description
Operating Manual PSSnet GW1 MOD-EtherCAT
1002692-EN-02
18
Data transfer
Max. data length per tele-
gram
Write data (Bit)
FC 05 (Write Single Coil)
1 Bit
FC 15 (Write Multiple Coils) 1 … 1968
Write data (Word)
FC 06 (Write Single Regis-
ter)
1 Word
FC 16 (Write Multiple Regis-
ters)
1 … 123 Words
Read and write data (Word) FC 23 (Read/Write Multiple
Registers)
Read 1 … 125 Words
Write 1 … 121 Words
Data transfer limits
Information
There may be some restrictions in data length, depending on the device that
is used. Please refer to the information stated in the operating manual of the
relevant unit.
Function codes (Client connections)
The connection Client can access the Gateway's data areas using the following function
codes (FC):
Data area
Modbus syntax
Example
FC 01
Read Coils
The connection Client reads
bit data from the connection
Server,
data length = 1 Bit, content,
content: input/output data
(data received from 0x)
FC 02
Read Discrete Input
The connection Client reads
bit data from the connection
Server,
data length = 1 Bit, content,
content: input/output data
(data received from 1x)
FC 03
Read Holding Register
The connection Client reads
word data from the connec-
tion Server,
data length = 1 Word,
content: diagnostic word
(data received from 4x)
FC 04
Read Input Register
The connection Client reads
word data from the connec-
tion Server,
data length = 1 Word,
content: diagnostic word
(data received from 3x)
4.2.3