Communications
6.1 PROFINET instructions (T-blocks)
Easy Book
Manual, 05/2009, A5E02486774-01
75
Note
Due to the asynchronous processing of TSEND_C, you must keep the data in the sender
area consistent until the DONE parameter or the ERROR parameter assumes the values
TRUE.
For TSEND_C, a TRUE state at the parameter DONE means that the data was sent
successfully. It does not mean that the connection partner CPU actually read the receive
buffer.
Due to the asynchronous processing of TRCV_C, the data in the receiver area are only
consistent when parameter DONE = 1.
TRCV_C establishes a TCP or ISO-on-TCP communication
connection to a partner CPU, receives data, and can
terminate the connection. After the connection is set up and
established, it is automatically maintained and monitored by
the CPU. The TRCV_C instruction combines the functions of
the TCON, TDISCON, and TRCV instructions.
●
To establish a connection, execute TRCV_C with parameter CONT = 1.
●
To receive data, execute TRCV_C with parameter EN_R = 1. Receive data continuously
when parameters EN_R = 1 and CONT = 1.
●
To terminate the connection, execute TRCV_C with parameter CONT = 0. The
connection will be aborted immediately and data could be lost.
Note
Ad hoc mode for TCP and ISO-on-TCP is not supported.
The "ad hoc" mode is not supported by the S7-1200. This affects the descriptions of the
TSEND_C, TSEND, TRCV_C and TRCV instructions in Section 6.2.4.2 "Open Ethernet
communication".