Panasonic FP Series Programming Manual page 898

Incremental and decremental counting with maximum target value control:
14000
10000
8000
4000
2000
1
2
0
1
3
2
3
4
y Elapsed value of high-speed counter
Execution condition
1
High-speed counter control flag
2
Output relay 0-4
3
Overview:
Maximum target value enabled
control:
Incremental counting: When the elapsed value reaches the
maximum target value:
The pointer of the data table
moves from target value 1
to the last target value.
Decremental counting: When the elapsed value reaches the
value -1:
The pointer of the data table
moves from the last target
value to target value 1.
Provided that neither a reset input nor a software reset is being used.
Hardware reset operation
Channel Hardware reset input
0 X2
1
2 X5
3
14000 Maximum target value
10000 Target value 4
8000 Target value 3
4000 Target value 2
2000 Target value 1
 the pointer returns to target
value 1
 output relay 0 turns to TRUE
 the elapsed value is set to 0
 the pointer returns to the last
target value
 the output relay corresponding
to the last target value turns to
TRUE
 the elapsed value is set to the
maximum target value
High-speed counter instructions
disabled (see note)
When the elapsed value reaches the last
target value:
 the pointer returns to target value 1
 output relay 0 turns to TRUE
 the elapsed value continues to
increment and restarts at the
minimum value of the ring counter
When the elapsed value reaches the
value -1:
 the pointer returns to target value n
 the output relay corresponding to
the last target value turns to TRUE
 the elapsed value continues to
decrement and restarts at the
maximum value of the ring counter
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