Aaeon MAX-Q670A, Installation Manual, Page: 56 / 80

Raptor MicroATX – Installation Guide
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Troubleshooting POST
Embedded BIOS writes progress codes, also known as POST codes, to
I/O port 80h during POST, in order to provide information to OEM
developers about system faults. These POST codes may be monitored
by a port 80h card in a PCI slot; they are not displayed on the screen.
Table B-1 Embedded BIOS 2000 POST Codes
Mnemonic Code Code System Progress Report
POST_STATUS_START 00h Start POST (BIOS is
executing).
POST_STATUS_CPUTEST 01h Start CPU register test.
POST_STATUS_DELAY 02h Start power-on delay.
POST_STATUS_
DELAYDONE 03h Power-on delay finished.
POST_STATUS_
KBDBATRDY 04h Keyboard BAT finished.
POST_STATUS_
DISABSHADOW 05h Disable shadowing & cache.
POST_STATUS_
CALCCKSUM 06h Compute ROM CRC, wait
for KBC.
POST_STATUS_
CKSUMGOOD 07h CRC okay, KBC ready.
POST_STATUS_BATVRFY 08h Verifying BAT command to
KB.
POST_STATUS_KBDCMD 09h Start KBC command.
POST_STATUS_KBDDATA 0ah Start KBC data.
POST_STATUS_
BLKUNBLK 0bh Start pin 23,24 blocking &
unblocking.
POST_STATUS_KBDNOP 0ch Start KBC NOP command.
POST_STATUS_SHUTTEST 0dh Test CMOS RAM shutdown
register.
POST_STATUS_
CMOSDIAG 0eh Check CMOS checksum.
POST_STATUS_CMOSINIT 0fh Initialize CMOS contents.
POST_STATUS_
CMOSSTATUS 10h Initialize CMOS status for
date/time.
POST_STATUS_
DISABDMAINT 11h Disable DMA, PICs.
POST_STATUS_
DISABPORTB 12h Disable Port B, video
display.