Siemens SIMATIC S7 F, Manual

Page: 219 / 354

Fail-Safe Blocks
Fail-Safe Systems
A5E00085588-03
8-31
8.3.3 F_SENDR
Function
This block safely sends 20 data items of the F_REAL data type to another CPU. It
can be received there by the F_RCVR block.
The data to be sent (e.g. outputs from other blocks) is stored at the inputs
SD_R_xx.
The data is transferred via safety frames.
If you want to temporarily switch off a data interchange that has been established
between two CPUs in order to reduce the load on the bus, you can assign the
value 0 to the input EN_SEND. In this case, no more data is sent to the recipient,
and the recipient outputs the configured substitute values. If communication
between the connection partners was already established, when data interchange
restarted with EN_SEND = 1, an acknowledgment is required on the recipient’s
side before the values sent are output again.
Startup Characteristics
After a startup (cold restart or warm restart), communication must first be
established between the communication partners. The F_SENDR signals this at
the SUBS_ON parameter with "1". The recipient (F_RCVR) outputs substitute
values during this time until communication between F_SENDR and F_RCVR via
the safety frame has started up and any acknowledgment required for reintegration
at F_RCVR has been made.
I/Os
Name Data Type Explanation Default
Inputs: EN_SEND BOOL 1 = switch transmission on
0 = switch transmission off
1
ID WORD ID addressing parameter 0000
R_ID DWORD R_ID addressing parameter 00000000
SD_R_00 F_REAL Send date 00 0
... ...
SD_R_19 F_REAL Send date 19 0
TIMEOUT F_TIME Monitoring time in ms for vital-
sign monitoring T#0 ms
CRC_IMP DWORD Address reference CRC Supplied
automatically
Outputs:
ERROR F_BOOL Transmission error 0
SUBS_ON F_BOOL Recipient outputs substitute
values 0
RETVAL WORD Error code 0000