Siemens Simantic Net NCM for Industrial Ethernet S7 - Manual (Page 148)

Programming FCs (Functions) and FBs for S7 Ethernet CPs
148
SIMATIC NET NCM S7 for Industrial Ethernet
C79000-G8976-C129–06
5.3 FCs for Configured Connections
Overview
The following functions (FCs) are available for transferring data over configured
connections:
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 in FCs for an S7-300 and S7-400
S
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
later versions, longer data records (up to 8092 bytes) can be transferred with
FCs AG_LSEND or AG_LRECV.
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 8092 bytes can be transferred.
S
S7-400:
With FCs AG_SEND / AG_RECV the data length per job is restricted to <=240
bytes.
Longer data records (up to 8092 bytes) can be transferred with FCs
AG_LSEND or AG_LRECV.
Please check the manual /3/ of the S7-CP you are using for the data areas
supported. 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.