Siemens PROFINET CP 343-1

Performance data
2.4 Characteristic data of the SEND/RECEIVE Interface
CP 343-1
Manual, 10/2012, C79000−G8976−C201-07
17
Data lengths of the S7 services
Table 2- 3 Possible data lengths of the S7 services
S7 service Maximum block length per frame
PUT / GET 160 bytes
USEND/URCV 160 bytes
BSEND/BRCV 32 kB
Execution times for FBs for S7 connections
The execution time required to process the function blocks (FBs PUT, GET, USEND, URCV,
BSEND, BRCV) required on the S7-300 / C7-300 CPU is decisive for the calculation of the
CPU cycle times (OB1) for S7 connections.
Note
Measurements of transmission and reaction times in Ethernet, PROFIBUS and PROFINET
networks for a series of configurations can be found on the Internet at the following address:
25209605 (http://support.automation.siemens.
com/WW/view/en/25209605)
2.4 Characteristic data of the SEND/RECEIVE Interface
The SEND/RECEIVE interface provides access to communication over TCP, ISOonTCP,
ISO transport and UDP connections.
The following characteristics are important:
Table 2- 4 Characteristic data of the SEND/RECEIVE interface
Characteristic Explanation / values
Number of ISO transport connections, ISO-on-
TCP connections + TCP connections + UDP
connections in total
16 maximum
Notes:
 All UDP connections are also possible in
multicast mode.
 Free UDP connections are supported by the
CP.
Maximum data length for the blocks AG_SEND
(as of V4.0) and AG_RECV (as of V4.0)
AG_SEND and AG_RECV allow the transfer of
blocks of data with the following lengths:
 1 to 8192 bytes for ISO transport, ISO-on-
TCP, TCP
 1 to 2048 bytes for UDP
Restrictions for UDP