Send/Receive Interface; Characteristic Data - Siemens SIMATIC NET S7-400 Manual

Performance data

2.3 SEND/RECEIVE interface

Note
Effects of connections in the SPEED SEND/RECV mode
Note the effects of connections on the SEND/RECEIVE interface that are used in the
SPEED SEND/RECEIVE mode.
The maximum configuration limits of S7 communication are reduced by each configured
connection using the SPEED SEND/RECV mode.
2.3 SEND/RECEIVE interface
2.3.1

Characteristic data

The SEND/RECEIVE interface provides access to communication over TCP, ISOonTCP,
ISO transport and UDP connections.
The following characteristics are important:
Characteristic
Number of SEND/RECEIVE connections
Number of SEND/RECV connections in
SPEED SEND/RECV mode
Maximum data length for AG_SEND and
AG_RECV program blocks
18
Explanation / values
TCP connections: 1...64
•
ISO-on-TCP connections: 1...64
•
ISO transport connections: 1...64
•
Total number of UDP connections (specified and free) that can be
•
configured: 1 to 64 (of those up to 48 in multicast mode)
Max. number of connections in total:
•
(ISO transport and ISOonTCP
+ TCP + UDP) <= 64
Refer to the example in section 5.1 (Page 17)
Notes:
Avoid overload at receiving end
• 1)
The flow control on TCP connections cannot control permanent over-
load of the recipient. You should therefore make sure that the pro-
cessing capabilities of a receiving CP are not permanently exceeded
by the sender (approximately 150200 messages per second).
The number depends on the CPU type being used.
Per CPU 412/414 maximum 30
•
Per CPU 416/417 maximum 62
•
AG_SEND and AG_RECV were shipped with other CPs of the S7-400
family and allowed the transfer of user data with a length of 1 to 240
bytes. The version of the CP described here continues to support these
program blocks.
1)
Manual, 03/2019, C79000-G8976-C299-04
CP 443-1 RNA