Stargazer <spamtrap@[EMAIL PROTECTED]
> wrote:
>On Mar 17, 8:44 pm, Cyril Novikov <spamt...@[EMAIL PROTECTED]
> wrote:
>> Stargazer wrote:
>> > ;
>> > mov al, CMD_EOI
>> > out PIC_MASTER, al
>> > cmp ebx, 8
>> > jb fin
>> > out PIC_SLAVE, al
>>
>> These 2 OUT's are what takes 2000+ cycles. The reason you see it
elsewhere is
>> most likely a bug in your measurement code.
>
>Why would it take 2000+ cycles? interrupt controller is integrated in
>a chipset which provides pretty fast access.
That is irrelevant. Cyril is quite correct. I/O ****t accesses take about
a microsecond, regardless of bus speed or where the ****t is located. Part
of this comes from the need to maintain historical compatibility.
--
Tim Roberts, timr@[EMAIL PROTECTED]
& Boekelheide, Inc.
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