Datasheet

APCI-3xxx Functions of the board
Upward counter
Fig. 8-9: Run down of the upward counter
After reaching the reload value, the counting value is set on 0 and continues
to be counted. At an overflow an interrupt can be generated.
Downward counter
Fig. 8-10: Run down of the downward counter
In order to get the same counting value as in the upwards mode, the reload
value must be set on 3. The counter counts down to 0 and will be reset to the
reload value from the next edge cycle on.
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