Introduction.

Workshop PG5
Resources
3.1.3 Interrupt
inputs
Some of our PCD’s have two inputs called INB1 and INB2. Each time you
have a rising edge on one of these inputs, the normal program cycle will be
interrupted and the PCD will execute a special program block called XOB20 or
XOB25 ( XOB20 for INB1 and XOB25 for INB2 ). These interrupt inputs are
on the following PDC's: PCD1.M120/130, PCD2.M120 and PCD6.M3.
These inputs are capable of a frequency up to 1000 times per second.
Instruction list program:
FUPLA program:
COB 0 ; Main program
0
ECOB
XOB 20 ; interrupt INB1
INC R 2 ; increment the register
; R 2
EXOB
( FBox: Integer, Addition )
Normal input cards have special filters on their inputs. These filters protect the
pin from noise with frequencies higher than 50Hz. Therefore you might have a
situation where you can't react on a signal because it is either to short, or
repeated to fast. In this situation, you can use these inputs as an interesting
alternative to expensive special counter cards like the PCD2.H1XX or
PCD4.H1XX. ( these cards count at speeds between 10 and 160 kHz )
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