VOGONS


LPT2

Topic actions

First post, by Hatta

User metadata
Rank Member
Rank
Member

Can I make LPT2 co-exist comfortably with a Soundblaster? They both want IRQ5 by default. The only free IRQ for the SB is 10, which I'm aware has some compatibility problems.

I have them both set to IRQ5 right now, and they appear to work. When would I expect to see a conflict and what sort of symptoms would I get? Is this a problem, and what sort of solutions are available?

I'm guessing the right thing to do is to disable the LPT2 jumper and just tape over the port. LPT2 is unidirectional only anyway, so no big loss. Still a second opinion is always nice.

Reply 2 of 5, by Hatta

User metadata
Rank Member
Rank
Member

LPT1 is on IRQ7. It's bidirectional, so I'd like to keep that one.

Hearing sounds when I print isn't a big deal. I'm not going to be printing while playing DOOM of course. I may just leave well enough alone if that's the only symptom of a conflict. I have also noticed that once in a while on a warm reboot LPT2 will not appear in the BIOS. Again, not a big deal.

The PC is a generic 486 VLB board with AMI bios, and the I/O card is this one. I can't find any identifiying information, but I got a card with jumper settings on it in the box. LPTs can only be assigned to 5 or 7.

Reply 4 of 5, by DonutKing

User metadata
Rank Oldbie
Rank
Oldbie

I had a scanner and printer attached to my 486 back in the day, so we had an additional LPT card installed in the PC. One was IRQ5 and the other was IRQ7.
We had a sound blaster 16 on IRQ5.

Gaming was fine, never had a problem. When we went to print something though we would get crackling noises through the sound blaster. A minor annoyance but hardly a big problem.

If you are squeamish, don't prod the beach rubble.

Reply 5 of 5, by h-a-l-9000

User metadata
Rank DOSBox Author
Rank
DOSBox Author

It's not very common that software uses the IRQ of a printer port. But if it does you may run into a problem.

1+1=10