Re: Strange BIOS-self-reset and IRQ-conflicts
From: Reiner Rosin (rr_at_wkl-lasertechnik.de)
Date: Thu, 18 Dec 2003 10:44:28 +0100
"Jens Nixdorf" <firstname.lastname@example.org> schrieb:
> Hi All,
> i have here an small linux with a kernel 2.4.18 (not modular) running at a
> 3,5"-SBC with VIA Eden Processor. For my application i dont need the
> parallel port, but many serial ports, so the kernel was built without
> parport-stuff and no parport devices are in the system. For the serial
> ports i'm using a 8-port-PC104-Card, which needs at least one IRQ. Because
> i dont need the parport, i set it off in the BIOS and give the free IRQ 7
> to the serial-card and all is running smoothly.
> My customer have sold some POS-systems based on the above mentioned
> now he comes with following problem: One of these systems seems to reset
> its BIOS to its defaults, and this includes: parallel port is active and
> has IRQ 7. And the system has heavy communication over the serial ports
> (remember: IRQ 7), so we have a massive performance breakdown.
I assume a hardware fault - the system simply loses it's bios settings ...
> My questions now are:
> 1. Is such a self reset possible? And what could be the reason for such
> behaviour? Normally there is no keyboard available at the machine to get
> into the BIOS and load the default settings, so i can exclude some
> "handmade error" by the service personal.
See above ...
> 2. How can i get the information whether the parallel port is active and
> using IRQ 7 from inside the running linux? lsmod, cat /proc/interrupts and
> ksyms doesnt work.
If you want to check the bios settings, you might want to try the /dev/nvram