OSDev.org

Hi,

After I begin to have FAT, I'm now at the FDC driver. My own was actually done, but it failed after one month of troubleshooting work on a real computer. Therefore, I've now resorted to a finished module of NeptuneOS and rewritten it for my OS. During this boot also works great on both an emulator and on real hardware. So it can be assumed that the works. However, after my shell is started and I would like for example the FAT read from a sector to analyze, there comes no IRQ6 from a fdc-routine anymore, accordingly, the system depends on the site since at IRQ6 wait.

A good example is the Seek. The MSF is able to read it so, whether the still seek and since I have seen that even if it no longer seek and IRQ6 should be sent in any case, no one comes. It is blocked somehow. But I will send to each of the 16 IRQs an EOI, IRQ6 should not be masked my opinion, because I never do this and a cli can not be guilty, because a IRQ1 for example, still comes through clean.

Now I am curious why the IRQ6 apparently comes no longer, when the shell with a syscall call a fdc-routine, although during the boot process still worked.

Christian
(Sorry for my bad english)

Have you read this: http://wiki.osdev.org/FDC ?

IRQ 6 gets turned off if bit 3 (value = 8) of the Digital Output Register is set. (port 0x3f2)

Does your shell turn on ACPI? Does the FDC driver fail in both the emulator and on real hardware, once the shell runs? What emulator are you using? Does it put an error message in the logging file?

On Qemu and VirtualBox all runs fine, during boot and at my shell.
I read the article, but not detailed, because i have read another arcticle on another os-dev-site about it.
Bit 3 in DOR is set all the time, i checked it. My Shell can't use ACPI. I don't have a logging file, because the fdc driver fails only with my shell and only on real hardware.

Emulator:
Boot: FDC Driver works
Shell (with Syscall): FDC Driver works

Real PC:
Boot: FDC Driver works
Shell (with Syscall): FDC Driver don't work