On Tue, 18 Nov 2003, Mlodzianowski Janusz wrote:
Does anyone have a datasheet for APIC 82489 chip? I could not find it anywhere..
AFAIK, it has never been published in an electronic form. Do you really have such a chip in any equipment? -- it's a ten years old design and it went out of production quite long ago. It was used for i486 and some early/unusual Pentium systems. Unless you need documentation for this very APIC implementation (which is a bit different from its derivatives), appropriate bits are included in other documents that are available at the Intel web site.
I understand that this chip is a replacement for I8259 used till now as an interrupt controller on a PC/AT. I would like to learn more, and to play with extra IRQs (IRQ15+) it provides.
The i82489DX has exactly 16 I/O interrupt entries, so that's not really that many more beyond what's been available in the i8259A setup as specified by the PC/AT architecture. Certain later APIC implementations (e.g. the i82093AA) have more interrupt entries and they are fairly well documented on-line.
Most modern PC chipsets support this chip am I correct?
If you're particularly interested in a PC-specific APIC setup, then you should consider getting "Multiprocessor Specification" and probably some ACPI docs as well.
Maciej