Appendix B: BIOS POST Codes
B-5
POST (hex) Defi nition
74h Reserved
75h Detect and install all IDE devices: HDD, LS120, ZIP, CD-ROM, etc.
76h Reserved
77h Detect serial ports and parallel ports
78h Reserved
79h Reserved
7Ah Detect and install co-processor
7Bh Reserved
7Ch Reserved
7Dh Reserved
7Eh Reserved
7Fh 1. Switch back to text mode if full screen logo is supported.
- If errors occur, report errors and wait for keys.
- If no errors occur or F1 key is pressed to continue:
- Clear EPA or customization logo
80h Reserved
81h Reserved
82h 1. Call chipset power management hook
2. Recover the text font used by EPA logo (not for full screen logo)
3. If password is set, ask for password
83h Save all data in stack back to CMOS
84h Initialize ISA PnP boot devices
85h 1. USB fi nal initialization
2. NET PC: Build SYSID structure
3. Switch screen back to text mode
4. Set up ACPI table at top of memory
5. Invoke ISA adapter ROMs
6. Assign IRQs to PCI devices
7. Initialize APM
8. Clear noise of IRQs
86h Reserved
87h Reserved
88h Reserved
89h Reserved
90h Reserved
91h Reserved
92h Reserved
93h Read HDD boot sector information for Trend anti-virus code