Introduction.

Workshop PG5
Resources
Counter Example:
We will program a counter which counts up each time the input 5 receives a
signal. Each time input 6 receives a signal, the counter will count down. (the
counts will be activated on the rising edge of the input signal). The counter can
be set to zero with a high on input 2. We will load the initial count with 3.
This is just an example. If you are a little confused, don’t worry you will understand
it better once we start actually writing some programs.
Load the counter:
LD C 35
3
Integer value:
Increment the counter:
INC C 35
Read the counter content
and display it on the output
LD C 35
0
Binary value:
Q equals high if the counter content
is not zero.
STH C 35
Solution:
Instruction list program: FUPLA program:
COB 0 ;Cyclic organization block
0 ;
STH I 1 ;If input 1 equals 1
LD C 35 ;then load the counter 35
3 ; with 3
STH I 2 ; If input 2 equals 1
LD C 35 ; then load the counter
0 ; with zero
STH I 5 ;If there's a rising edge
DYN F 13 ;on input 5
INC C 35 ;then increment the counter 35
STH I 6 ;If there's a rising edge
DYN F 14 ;on input 6
DEC C 35 ;then decrement the counter
ECOB
( FBox:
Counters, UP-Down pre-set and
clear)
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