Siemens SIMATIC CP 340 User Manual page 120

Communication using function blocks
6.5 Use of function blocks for reading and controlling the RS 2332C secondary signals
Setting/resetting interface outputs of the CP 340
The user can set or reset the interface outputs via the corresponding parameter inputs of the
V24_SET FC. The V24_SET FC is called in the cycle or alternatively in a time-controlled
program statically (without conditions).
The binary result is not affected. The function does not issue error messages.
The LADDR parameter defines the CP 340 to be addressed.
Block call
STL representation
CALL V24_SET
LADDR: =
RTS: =
DTR: =
Note
The EN and ENO parameters are only present in the graphical representation (LAD or FBD).
To process these parameters, the compiler uses the binary result. The binary result is set to
signal state "1" if the block was terminated without errors. If there was an error, the binary
result is set to "0".
Assignment in the data area
The V24_SET function does not occupy any data areas.
V24_SET (FC 6) parameters
The table below lists the parameters of the V24_SET function (FC 6).
Table 6- 6 V24_SET (FC 6) parameters
Name Type Data type
LADDR INPUT INT
RTS INPUT BOOL
DTR INPUT BOOL
120
Comment
CP 340 base address
Request to send,
CP 340 ready to send
Data terminal ready,
CP 340 ready (see Chapter "RS 232C
accompanying signals (Page 46)")
LAD representation
Permitted values, remark
The base address is taken from STEP 7.
(Control CP 340 output)
(Control CP 340 output)
PtP coupling and configuration of CP 340
Manual, 04/2011, A5E00369892-03