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HP Vectra VL400 User Manual

Page 51

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51

4 BIOS Overview

Order in Which the POST Tests are Performed

0Fh

Initialize the local bus IDE

10h

Initialize Power Management

11h

Load alternate registers with initial POST values

12h

Restore CPU control word during warm boot

13h

Initialize PCI Bus Mastering devices

14h

Initialize keyboard controller

17h

Initialize cache before memory autosize

18h

8254 timer initialization

1Ah

8237 DMA controller initialization

1Ch

Reset Programmable Interrupt Controller

24h

Set ES segment register to 4 GB

26h

Enable A20 line

28h

Autosize DRAM

29h

Initialize POST Memory Manager

2Ah

Clear 512 KB base RAM

32h

Test CPU bus-clock frequency

33h

Initialize POST Dispatch Manager

34h

Test CMOS RAM

35h

Initialize alternate chipset registers

36h

Warm start shutdown

37h

Reinitialize the chipset (MB only)

38h

Shadow system BIOS ROM

39h

Reinitialize the cache (MB only)

3Ah

Autosize cache

3Ch

Configure advanced chipset registers

Checkpoint

Code

POST Routine Description