Behavior Of The Digital Inputs; Gate Functions In Count Modes - Siemens SIMATIC ET 200S Operating Instructions Manual

3.6.5

Behavior of the Digital Inputs

Digital Input of the 1Count5V/500kHz
The DI digital input can be operated with 24 V sensors (P switch and series mode).
In the case of the input and HW gate functions, the level of the digital input can be inverted
by means of parameter assignment.
The STS_DI feedback bit indicates the level of the digital input.
3.6.6

Gate Functions in Count Modes

Software Gate and Hardware Gate
The 1Count5V/500kHz has two gates
• A software gate (SW gate), which is controlled by the SW_GATE control bit.
• A hardware gate (HW gate), which is controlled by means of the digital input on the
Internal gate
The internal gate is the logical AND operation of the HW gate and SW gate. Counting is only
active when the HW gate and the SW gate are open. The STS_GATE feedback bit (internal
gate status) indicates this. If a HW gate has not been assigned, the setting of the SW gate is
decisive. Counting is activated, interrupted, continued, and canceled by means of the
internal gate. In the Count once counting mode, the internal gate is closed automatically
when there is an overflow/underflow at the counting limits.
Canceling- and Interrupting-Type Gate Function
When assigning the gate function ("Gate Function" parameter), you can specify whether the
internal gate is to cancel or interrupt counting. When counting is canceled, after the gate is
closed and restarted, counting starts again from the beginning. When counting is interrupted,
after the gate is closed and restarted, counting continues from the previous value.
Technological Functions
Operating Instructions, 02/2007, A5E00124867-05
The software gate can only be opened by a positive edge of the SW_GATE control bit. It
is closed when this bit is reset. Note the transfer times and run times of your control
program.
1Count5V/500kHz. You assign the hardware gate as the function of the digital input
(Function DI "HW Gate"). It is opened on a positive edge at the digital input and closed on
a negative edge.
1Count5V/500kHz
3.6 Count Modes
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