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SubjectRe: ide-cd problem
Date
On Sunday 21 November 2004 16:13, Alan Chandler wrote:
...
>
> This seems to be some combination of frequently occuring timing problem,
> and the difference treatment in cdrom_newpc_intr to cdrom_pc_intr

I put a ndelay(400) at the head of cdrom_newpc_intr and the problem of DRQ
being set when there was no data to transfer disappeared. It appears that my
hardware is too slow.

I have been reading the ATA/ATAPI - 6 spec, and it implies that the state of
DRQ line need one pio cycle before being correct and that you should read the
alternative status register to achieve this. I tried a simple

HWIF(drive)->INB( IDE_ALTSTATUS_REG);

But that made no difference.



--
Alan Chandler
alan@chandlerfamily.org.uk
First they ignore you, then they laugh at you,
then they fight you, then you win. --Gandhi
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