Acer Extensa 4420 TravelMate 4520/4220, Extensa 4420/4120 Service Guide - Page 84

Code 6Eh 70h 72h 76h 7Ch 7Eh 80h 81h 82h 83h 84h 85h 86h 87h 88h 89h 8Ah 8Bh 8Ch 8Fh 90h 91h 92h 93h 95h 96h 97h 98h 99h 9Ah 9Ch 9Dh 9Eh 9Fh A0h A2h A4h A8h 74 Beeps 1-2 POST Routine Description Display possible high address for UMB recovery Display error messages Check for configuration errors Check for keyboard errors Set up hardware interrupt vectors Initialize coprocessor if present Disable onboard Super I/O ports and IRQs Late POST device initialization Detect and install external RS232 ports Configure non-MCD IDE controllers Detect and install external parallel ports Initialize PC-compatible PnP ISA devices Re-initialize onboard I/O ports Configure motherboard configurable devices (optional) Initialize BIOS Area Enable Non-Maskable Interrupts (NMIs) Initialize Extended BIOS Data Area Test and initialize PS/2 mouse Initialize floppy controller Determine number of ATA drives (optional) Initialize hard-disk controllers Initialize local-bus hard-disk controllers Jump to UserPatch2 Build MPTABLE for multi-processor boards Install CD ROM for boot Clear huge ES segment register Fixup Multi Processor table Search for option ROMs. One long, two short beeps on checksum failure. Check for SMART drive (optional) Shadow option ROMs Set up Power Management Initialize security engine (optional) Enable hardware interrupts Determine number of ATA and SCSI drives Set time of day Check key lock Initialize typematic rate Erase F2 prompt Chapter 4