Parallel Port: Can status bits be used as outputs?

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Hi,

I know a lot of people want to use parallel port outputs as inputs; I
have the opposite dilemma.

I am working on a particular application where it would be far more
convenient to use pins 10-13 on the parallel port (normally status
bits) as outputs. Otherwise I would have to create custom cabling
which would be rather inconvenient.

Is it possible to use pins 10-13 as outputs on most PC parallel ports?
Could doing so damage the card or PC?

Thanks,
Steve Lieberman

 

Steve,

I tried briefly to do this without much luck. I believe it is possible
but you need to use a the parallel port subsystem. My quick solution
was to use two 373 latches and the eight data bits of the parallel
port. Using one of the bits as chip select, I was able to get 14 I/O
pins.

Chandler (Chandler923 at hotmail dot com)

 

Is it possible to use pins 10-13 as outputs on most PC parallel ports?

Sorry, mate - you're out of luck. There's no way to control those bits.

--J.

 

PIN 1 Strobe/ Output
PIN 2 Data0 Bidir
PIN 3 Data1 Bidir
PIN 4 Data2 Bidir
PIN 5 Data3 Bidir
PIN 6 Data4 Bidir
PIN 7 Data5 Bidir
PIN 8 Data6 Bidir
PIN 9 Data7 Bidir
PIN 10 Ack/ Input
PIN 11 Busy Input
PIN 12 Paper Empty Input
PIN 13 Select Input
PIN 14 Autofeed/ Output
PIN 15 Error/ Input
PIN 16 Init Output
PIN 17 Select Input/ Output
PIN 18-25 GND

And there's is no way to change that!!!