HP Vectra VL800, Technical Reference Manual

Page: 126 / 147

126
7 Tests and Error Messages
Order in Which POST Tests Are Performed
Order in Which POST Tests Are Performed
Each time the system is powered on, or a reset is performed, the POST is
executed. The POST process verifies the basic functionality of the system
components and initializes certain system parameters.
The POST starts by displaying the HP PC logo when the PC is restarted. If
you wish to view the POST details, press
Esc
to get the HP Summary
Screen.
If the POST detects an error, the screen switches to text mode, and a
detailed error message is displayed inside a view system errors screen, in
which the error message utility (EMU) not only displays the error diagnosis,
but the suggestions for corrective action (refer to
page 134 for a brief
summary).
Devices such as memory and newly installed hard disks, are configured
automatically. The user is not requested to confirm the change.
During the POST, the BIOS and other ROM data are copied into high-speed
shadow RAM. The shadow RAM is addressed at the same physical location
as the original ROM in a manner which is completely transparent to
applications. It therefore appears to behave as very fast ROM. This
technique provides faster access to the system BIOS firmware.
The following table lists the POST checkpoint codes and their associated
beeps. Refer to
page 124 for more details about pre-boot diagnostics error
codes.
Checkpoint
Code
POST Routine Description
Beep
Code
02h Verify Real Mode
03h Disable Non-Maskable Interrupt (NMI)
04h Get CPU type
06h Initialize system hardware
08h Initialize chipset with initial POST values
09h Set IN POST flag