APPENDIX
IB770 User’s Manual
55
POST (hex)
Description
1Bh
Initial interrupts vector table. If no special specified, all H/W
interrupts are directed to SPURIOUS_INT_HDLR & S/W
interrupts to SPURIOUS_soft_HDLR.
1Dh
Initial EARLY_PM_INIT switch.
1Fh
Load keyboard matrix (notebook platform)
21h
HPM initialization (notebook platform)
23h
1. Check validity of RTC value:
e.g. a value of 5Ah is an invalid value for RTC minute.
2. Load CMOS settings into BIOS stack. If CMOS checksum fails,
use default value instead.
3. Prepare BIOS resource map for PCI & PnP use. If ESCD is
valid, take into consideration of the ESCD’s legacy information.
4. Onboard clock generator initialization. Disable respective clock
resource to empty PCI & DIMM slots.
5. Early PCI initialization:
-Enumerate PCI bus number
-Assign memory & I/O resource
-Search for a valid VGA device & VGA BIOS, and put it
into C000:0.
27h
Initialize INT 09 buffer
29h
1. Program CPU internal MTRR (P6 & PII) for 0-640K memory
address.
2. Initialize the APIC for Pentium class CPU.
3. Program early chipset according to CMOS setup. Example:
onboard IDE controller.
4. Measure CPU speed.
5. Invoke video BIOS.
2Dh
1. Initialize multi-language
2. Put information on screen display, including Award title, CPU
type, CPU speed … .
33h
Reset keyboard except Winbond 977 series Super I/O chips.
3Ch
Test 8254
3Eh
Test 8259 interrupt mask bits for channel 1.
40h
Test 8259 interrupt mask bits for channel 2.
43h
Test 8259 functionality.
47h
Initialize EISA slot
49h
1. Calculate total memory by testing the last double word of each
64K page.
2. Program writes allocation for AMD K5 CPU.
