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Acer 3300S User Manual

Page 71

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65

Chapter 4

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 and VGA BIOS, and put it into C000:0

24h

Reserved

25h

Reserved

26h

Reserved

27h

Initialize INT 09 buffer

28h

Reserved

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.

2Ah

Reserved

2Bh

Reserved

2Ch

Reserved

2Dh

1. Initialize multi-language
2. Put information on screen display, including Award title, CPU type, CPU speed...

2Eh

Reserved

2Fh

Reserved

30h

Reserved

31h

Reserved

32h

Reserved

33h

Reset keyboard except Winbond 977 series Super I/O chips.

34h

Reserved

35h

Reserved

36h

Reserved

37h

Reserved

38h

Reserved

39h

Reserved

3Ah

Reserved

3Bh

Reserved

3Ch

Test 8254.

3Dh

Reserved

3Eh

Test 8259 interrupt mask bits for channel 1

3Fh

Reserved

40h

Test 8259 interrupt mask bits for channel 2.

41h

Reserved

42h

Reserved

Checkpoint

Description