Siemens LOGO! Series Manual page 41

At each positive edge at the Cnt input, the internal counter is incremented
by one (Dir = 0) or decremented by one (Dir = 1). If the internal count
value is greater than or equal to the value specified for Par, the output (Q)
is set to 1. You can use the reset input to reset the internal count value to
'0000'. As long as R=1, the output is 0.
Note
If you switch off LOGO!'s power supply, the internal count value is de-
leted. After power on, the internal count value is zero (Cnt=0000).
Example:
Reset I2
Count I1
Dir Lo
Par=10
Whenever I1 takes on the state 1, the internal count value is incremented
by 1. As soon as the internal count value (Cnt) reaches the value 10 set by
means of Par, the output of the counter is set to 1.
LOGO! manual
EWA 4NEB 712 6006-02
Q1
Programming LOGO!
35