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3 function codes (client connections), Function codes (client connections) – Pilz PSSnet GW1 MOD-EtherCAT User Manual

Page 18

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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