Floppy IRQ wont fire

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Fadekraft
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Floppy IRQ wont fire

Post by Fadekraft » Sun Nov 06, 2011 1:04 am

Well ok not completly true, it will fire in emulators, but not on real hardware, and I'm using the code given in the tutorial.

It hangs forever when waiting for the IRQ in ResetFloppy.

It works however on Bochs, VirtualPC and VMWarePlayer. Any ideas to what could cause this problem?

Andyhhp
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Re: Floppy IRQ wont fire

Post by Andyhhp » Sun Nov 06, 2011 6:41 pm

What real hardware are you using to test on?

If it is very old hardware, it might have non-standard floppy controler, and if it is very new hardware, it might not have a floppy controller at all.

~Andrew
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Fadekraft
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Re: Floppy IRQ wont fire

Post by Fadekraft » Sun Nov 06, 2011 6:52 pm

1 Laptop, 2 desktop pc's. 1 of them 3 years old, the other new.

The floppy drive I'm using is a USB-floppy, so it would be through legacy support. I dunno if that would be a problem to be honest.

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Re: Floppy IRQ wont fire

Post by Andyhhp » Sun Nov 06, 2011 7:28 pm

That almost certainly will be the problem.

During boot, the BIOS will emulate access to the floppy drive via int 0x13.

However, when you jump into protected mode, you loose the BIOS support and your USB floppy drive will be a plain regular USB device rather than a floppy device.

Therefore, you will need a USB driver to talk to it again, or to jump back into real mode and reuse int 0x13

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Fadekraft
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Re: Floppy IRQ wont fire

Post by Fadekraft » Sun Nov 06, 2011 11:04 pm

Well that settles that then, so much for an USB Floppy drive.

Thanks for the response!

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