Port 0x80 writes considered harmful

I have had quite some problems with the parallel port on a computer of the model "F@MILY net" (details available on request). While Linux was running there would constantly be changing output lines on the parallel port.

The problem was observed with different kernel versions and even a 2.4.19 kernel stripped so much down that it could merely boot and panic because of missing root filesystem drivers.

I found that if I from a userspace program using ioperm and outb blocked interrupts the output would stop. I busylooped for a few seconds using the TSC, and then reenabled interrupts while interrupts was disabled there was no activity on the parallel port.

Then I inserted port 0x80 writes in the loop, and at that point there would be parallel port output during the entire execution of the loop.

What would be the best solution to my problem?

Kasper Dupont -- der bruger for meget tid på usenet.
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for(_=52;_;(_%5)||(_/=5),(_%5)&&(_-=2))putchar(_);

If the parallel port is picking up 0x80 writes then either its at a very weird and very stupid address or its got some kind of decode problem.