Command: Set Counter - Siemens simatic s7-400 FM 450-1 User Manual

8.11

Command: Set counter

Overview
If you want to start or continue the counting process of a counter from a specific value (the
load value), you must assign parameters for the signal with which the counter is to be set to
the load value. You can set the counter as follows:
● With the L_DIRECT input parameter of the FC_CNT_CTRL
● With an external signal either via input 1I2 (2I2) or via the input in conjunction with the
This section describes the different methods and the time sequence for setting a counter.
Load value
Any number within the count range can be set for the load value.
The load value is interpreted according to the selected count range. If, for example, you
specify FFFF FFFF H as the load value, this is interpreted as 4 294 967 295 within the count
range 0 to +32 bit and as -1 within the count range -31 to +31 bit.
The load value is entered in the DB of the FC°CNT_CTRL.
Setting the counter via the user program
Regardless of the external events, you can set a counter with the FC°CNT_CTRL by means
of the L_DIRECT input parameter. This is also possible while a count is in progress.
The input parameter L_DIRECT is reset by FC CNT_CTRL once the job is successful
completed.
If you set the counter via the FC_CNT_CTRL call, setting cannot trigger a hardware interrupt.
Counter module FM 450-1
Manual, 02/2014, A5E03648739-02
zero mark of the encoder.
Modes, settings, parameters and commands
8.12 Initiating a process interrupt
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