Re: [PARPORT] Two or more interrupt-driven devices?

Matthias Jim Knopf (
Fri, 12 Mar 1999 17:09:49 +0100 (MET)


> Recently I succesfully designed a program that could use parport ( connect
> a pushbutton to Pin 10) as a method to generate an interrupt to wake up some
> process. But, now I need more pushbuttons to wake up different processes,
> while there is only one pin of parport I can connect. How to deal with
> other buttons? The way I think can be
> 1) Using bi-direction method, I can read info about which button is
> pressed by reading from the data port after the interrupt is generated(of
> course I have to connect each button both to pin 10 and one data port).
> 2) Use other input pins.
> Are they feasible? Any new ideas or suggestions?
Once i built an interface-card with 10 outputs (8 bit plus 2 that I
can't remember... I think it was pin 13+14 (Select + AutoFeed))
and 3 input-bits (pins 10-12: Ack, Busy + paper out)
                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ maybe these may
help you!
All of the mentioned pins ought to be able to be set or reset rather
than just triggered (as for example "Initialize Printer" would)

Still another method of using buttons or such things may be the
game-port as it supports 4 buttons.

So far, Jim (Matthias Knopf)

No RISC, No Fun           PGP-Key available
ORIGIN: Windows - from the man who brought us EDLIN.COM

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This archive was generated by hypermail 2.0b3 on Fri 12 Mar 1999 - 15:18:59 EST