Introduction.

Workshop PG5 Exercise Chapter 4
Counters and blinker :
Example:
Parking lot
Output 17
(red light) is
lit as soon as
the parking
lot is full
(Lot_full)
Input 0
( NewCar )
Input 1
( Car_leaving )
You have a parking lot with 8 parking slots.
You have to sensors : One at the entrance gate which gives a pulse each time a car
enters. Input 0 (NewCar ) a second one tells you when a car is leaving (input 1
Car_leaving ).
A signal ( output 17 Lot_full ) starts blinking as soon as 8 cars are in the parking lot.
Cars can enter the lot even if the lot is already full !!
Set the counter to 0 when you start up.
Goal:
You learn to know the different types of counters we have.
You learn to document the program.
You'll use a blinker.
You learn how to create a reset signal at start up.
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