Festo CPX-P-8DE-N Series, Описание

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3. Input module CPX-P-8DE-N-...
3-22
Festo P.BE-CPX-P-EA-EN en 1209NH English
Steps Description Status
1. Reset start/stop bit
in the PIO
Stop the current function in order to
avoid undefined states Counter is stopped
2. Parameterise
counter
•
Specify limit values ( Tab. 3/32
and Tab. 3/33)
•
Specify counter type (increment-
al/decremental counter) and
edge polarity (
Tab. 3/30)
•
Select input mode “Counter”
(
Tab. 3/20)
Input channel is initialised automat-
ically (
3.3.8):
– Limit values are loaded
– Counter is stopped
– Signal bit for limit value = 0
– Status LED not illuminated (off )
3. Use counter
•
Start counter
•
Set start/stop bit in the PIO
(start/stop = 1) – Signal edges are counted until
the stop value is reached.
– Status LED flashes (2 Hz)
1)
– upon reaching the limit value the
bit is set in byte 0 of the PII
•
Stop counter
•
Reset start/stop bit in the PIO
(start/stop = 0) – Input signal edges are no longer
counted.
– Counter remains at the current
value.
– Status LED is off
•
Reset counter
•
Reset signal via the PIO:
a) Bit Reset = 1 (min. 1 cycle)
b) Bit Reset = 0
– Limit value is loaded
– Signal bit for limit value = 0
– Counter remains in the current
state (started or stopped)
– Status LED not illuminated (off )
– Counter value
reached - end of the
counting range
(stop value)
– Counter value = stop value Counter is stopped (restart via reset
and start via PIO)
– Signal bit for limit value = 1
– Status LED illuminated
1)
Status LED flashes as long as the counter is active and the stop value has not yet been reached.
Tab. 3/14: Procedure for counters