Re: PROBLEM: floppy motor spins when floppy module not installed

From: Måns Rullgård
Date: Fri Dec 12 2003 - 10:13:35 EST


"Richard B. Johnson" <root@xxxxxxxxxxxxxxxxxx> writes:

> On Fri, 12 Dec 2003, [iso-8859-1] Måns Rullgård wrote:
>
>> Dale Mellor <dale@xxxxxxxxxxxxxxxxxxxx> writes:
>>
>> > 1. Floppy motor spins when floppy module not installed.
>>
>> It's a known problem. Some broken BIOSes don't turn off the motor
>> after probing for a disk. One solution is to change the boot priority
>> in the BIOS settings so the hard disk is tried before floppy. If you
>> ever need to boot from a floppy, you can change it back.
>
> It is not a broken BIOS! The BIOS timer that ticks 18.206 times
> per second has an ISR that, in addition to keeping time, turns
> OFF the FDC motor after two seconds of inactivity. This ISR is taken
> away by Linux. Therefore Linux must turn off that motor! It is a
> Linux bug, not a BIOS bug. Linux took control away from the BIOS
> during boot.

OK, but why doesn't it affect all machines?

--
Måns Rullgård
mru@xxxxxx

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