Datasheet

Functions of the board APCI-3xxx
8.8 Timer
The 16-bit timer is a downwards counter that can generate an interrupt after
the reload value (timeout). With the timer a time base is provided
independent from the PC clock, with which for example operations can be
synchronized.
The status of the counter value and of the reload value as well as the status
and interrupt register can be read back through software.
The operation states can be read back. As time bases for the timer three
different clock signals (μs, ms, s) can be used.
8.9 Counter
On the APCI-3xxx 3 x 16-bit counter inputs are available. Each of these
counters can be programmed through software.
The counter inputs are called by the 24 V input channels 0 to 2. If the
counter function is not used, the channels are available as standard digital
inputs.
Each counter has the following characteristics:
- 2 counting modes: The counter is programmed as upwards or downwards
counter.
- After reaching the reload value or when the counter ran off, an interrupt
can be generated.
- Reload value: 16-bit
- Clock: The counter counts at falling or rising edge or with each edge.
- Trigger function: Sets the counter to its start value 0 in the
upwards mode = clear function
Reload value in the downwards mode
- Clear function: The counter state is deleted (reload and counting value
are set on 0)
- The 3 counters can be initialized, started or stopped simultaneously
through synchronous control.
- The status of the inputs 0 to 2 can be read through external clock.
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