MEM FEC00000h - Pentium - 82379AB I/O APIC - I/O REGISTER SELECT Size: DWORDDoubleword; four bytes. Commonly used to hold a 32-bit segment:offset or selector:offset address. Desc: bits 7-0 of the I/O Register Select memory location specify which of the APIC's registers appears in the I/O Window at FExxx010h Range: the Multiprocessor Specification calls for I/O APICs to be memory- mapped on 4K boundaries between FEC00000h and FEDFC000h; the Intel 82379AB I/O APIC can be memory-mapped on any 1K boundary within FEC0000h-FEC0F800h Note: this memory-mapped register is also supported by the Intel 82093AA I/O APIC SeeAlso: MEM FEC00010h,MEM FEE00000h,MEM xxxxh:xxx0h"Multiprocessor"