Talk:APIC: Difference between revisions

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(Re: APIC in uniprocessor x86 machines)
(APIC Timer Check)
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The idea is, you can simply forget about the APIC when dealing with uniprocessor machines, even though some of its features are very useful to the developer. Most of the useful contents is completely independent of a multiprocessor machine anyway. - [[User:Combuster|Combuster]] 15:32, 8 July 2007 (CDT)
The idea is, you can simply forget about the APIC when dealing with uniprocessor machines, even though some of its features are very useful to the developer. Most of the useful contents is completely independent of a multiprocessor machine anyway. - [[User:Combuster|Combuster]] 15:32, 8 July 2007 (CDT)
(追記) (追記ここまで)
(追記) ==Sanity APIC Timer Check== (追記ここまで)
(追記) So, I attempted to condense Brendan's timer using CPU speed detection code in English. Could anyone check it over for mistakes? (追記ここまで)
(追記) (追記ここまで)
(追記) *Init the PIT at 4hz and setup the APIC timer. (追記ここまで)
(追記) *Wait for the PIT to start. (追記ここまで)
(追記) *Set the APIC timer count to 0xFFFFFFFF, and start. (追記ここまで)
(追記) *Wait for next PIT IRQ. (追記ここまで)
(追記) *Stop the APIC and PIT timers. (追記ここまで)
(追記) *((0xFFFFFFFF - APIC's current count) * 32) / frequency / divider = New APIC count (追記ここまで)
(追記) --[[User:Alboin|Alboin]] 18:18, 9 June 2008 (CDT) (追記ここまで)

Revision as of 23:18, 9 June 2008

The original quick conversion was a bit of a mess. This is my 1st whack at cleaning it up a bit. I think it looks much better now. ;) I can't find JHawthorn's instructions on how to fix the Forum links in the See Also section -- sorry. Bewing 01:56, 19 March 2007 (CDT)

FYI: Post:83433 ;) - Combuster 04:52, 19 March 2007 (CDT)

Thanks for that link -- OK, I fixed those See Also links. Bewing 21:49, 5 April 2007 (CDT)

APIC in uniprocessor x86 machines...

The article seems to focus on APIC being multiprocessor machines, but in fact many older AMD/Intel machines have an option in BIOS that allows PIC/APIC selection. - Brynet-Inc (Please sign your posts)

The idea is, you can simply forget about the APIC when dealing with uniprocessor machines, even though some of its features are very useful to the developer. Most of the useful contents is completely independent of a multiprocessor machine anyway. - Combuster 15:32, 8 July 2007 (CDT)

Sanity APIC Timer Check

So, I attempted to condense Brendan's timer using CPU speed detection code in English. Could anyone check it over for mistakes?

  • Init the PIT at 4hz and setup the APIC timer.
  • Wait for the PIT to start.
  • Set the APIC timer count to 0xFFFFFFFF, and start.
  • Wait for next PIT IRQ.
  • Stop the APIC and PIT timers.
  • ((0xFFFFFFFF - APIC's current count) * 32) / frequency / divider = New APIC count

--Alboin 18:18, 9 June 2008 (CDT)

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