Siemens SIMATIC NET S7-300 User Manual

7 Programming FCs (Functions) and FBs for S7 Ethernet CPs
A-188
S7-CPs for Industrial Ethernet Configuring and Commissioning
Release 01/2007
C79000-G8976-C182-07
7.3 FCs for the SEND/RECEIVE Interface
Overview
The following FCs are available for transferring data on the SEND/RECEIVE
interface:
FC
Can be used with
1)
Meaning
S7 - 300 S7 - 400
AG_SEND (FC5) x x for sending data
AG_RECV (FC6) x x for receiving data
AG_LSEND (FC50) x for sending data
AG_LRECV (FC60) x for receiving data
1)
Notes on the FCs for an S7-300 and S7-400
 S7-300:
With older versions of the Ethernet CPs, the data length per job is restricted to
<=240 bytes (applies up to block version V3.0 of AG_SEND / AG_RECV).
With the latest versions of the Ethernet CPs, only FCs AG_SEND and
AG_RECV are used; due to a new and more efficient internal protocol, the data
up to 8192 bytes can be transferred.
 S7-400:
With FCs AG_SEND / AG_RECV the data length per job is restricted to <=240
bytes.
Longer data records (up to 8192 bytes) can be transferred with FCs
AG_LSEND or AG_LRECV.
Please check the supported data area in the device-specific Part B of this manual
for the S7-CP you are using. You will find an overview of the versions of the
FCs/FBs in the documentation and block history.
Application
The following diagram illustrates the use of the FCs described here for
bi-directional data transfer on one configured connection.

Siemens SIMATIC NET S7-300 Specifications

General

Product Type Designation	SIMATIC NET S7-300
Mounting	DIN rail mounting
Protection Class	IP20
CPU Models	Various models available (e.g., CPU 312, CPU 314)
Communication Interfaces	MPI, PROFIBUS DP
Power Supply	24 V DC power supply required. Different power supply modules available.
I/O Modules	Digital input modules, digital output modules, analog input modules, analog output modules
Programming	STEP 7 software
Supply Voltage	24V DC or 120/230V AC (depending on model)
Digital Inputs	Available via digital input modules
Digital Outputs	Available via digital output modules
Analog Inputs	Available via analog input modules
Analog Outputs	Available via analog output modules
Communication Functions	MPI, PROFIBUS DP, Ethernet (depending on model)
Protocols	MPI, PROFIBUS DP, TCP/IP (depending on model)
Operating Temperature	0°C to 60°C
Storage Temperature	70 °C
Memory	Depends on CPU model (e.g., 32 KB to 1.5 MB)