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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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