HP A7818-IE002 - Manual (Page 86)

Tests And Error Messages
Order In Which POSTs Occur
Chapter 4 86
Order In Which POSTs Occur
The POST executes each time the system is powered on or a reset is performed. The
POST process verifies the basic functionality of the system components and initializes
certain system parameters.
The POST starts by displaying a graphic screen of the HP PC Workstation’s logo when
you restart the system. If you want to view the POST details, press
Esc to access the HP
Summary Screen.
If the POST detects an error, the screen switches to text mode and a detailed error
message appears on a View System Errors screen. On this screen, the error message
utility (EMU) not only displays the error diagnosis but suggests corrective action. (Refer
to page 93 for a brief summary.)
On the HP Workstation x2100, the LCD status panel displays either a message, a POST
code number (refer to Table 4-4), or an EMU code.
Devices such as memory and newly installed hard disks are configured automatically.
You don’t need to confirm the change.
During the POST, the system copies BIOS and other ROM data into high-speed shadow
RAM. The shadow RAM is addressed at the same physical location as the original ROM
in a manner that is completely transparent to applications. Therefore, shadow RAM
appears to behave as very fast ROM. This technique provides faster access to the system
BIOS firmware.
Table 4-4 lists the POST checkpoint codes and their associated beeps. See page 81 for
more details about preboot diagnostics error codes.
Table 4-4 POST Checkpoint Codes
Checkpoint
Code
POST Routine Description
MaxiLife LCD
Display Message
Beep
Codes
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 POST Start
0Ah Initialize CPU registers CPU Regist. Init
0Bh Enable CPU cache
0Ch Initialize caches to initial POST values
0Eh Initialize I/O component I/O Init.
0Fh Initialize the local bus IDE IDE Init.
10h Initialize power management