Siemens SIMATIC S7-1200 Reference Manual page 64

Basic instructions
Instruction
✔ ✔ ✔
TSEND/TRCV
✔ ✔
TSEND_C/TRCV_C
(connection establishment
✔ ✔
and
termination are integrated)
(✔) ✔ ✔
TUSEND/TURCV
(not S7-300)
A5E33284667-AF
Extended instructions
Logs Property of
the data
transfer
TCP or Reliable with
ISO-on-TCP acknowledgment
UDP Fast, without
acknowledgment
Technology
Data package size Application and
application example
Exchange large data volumes with
<= 64 KB
acknowledgment. For example: Send
Exception S7-1200: data block with measured value logs to
<= 8 KB any network node.
Distribute larger amounts of data without
acknowledgment. For example: Distribute
position data quickly to many devices.
Integrated interface:
Max. 1472 bytes
An exact calculation of the limits is
available in the controller manuals.
CP on S7-300/400:
Max. 2048 bytes
Communication
Page 63