Core Bios Features; Multi Boot; Quiet Boot; Boot Block - Compal JHL90 Service Manual

JHL90 Service Manual
3.

Core BIOS Features

3.1

Multi Boot

The notebook can support Multi-Boot for selecting the boot sequence of Hard
Drive, Removable Devices, CD-ROM/DVD Drive and Network in Setup.
3.2

Quiet Boot

Quiet Boot replaces the customary technical messages during POST with a more
visually pleasing and comfortable display (OEM screen). During POST, right
after the initialization of VGA, The notebook displays an illustration called the
OEM screen during system boot instead of the traditional POST screen that
displays the normal diagnostic messages.
The OEM screen stays up until just before the operating system loads unless:
• Pressing <Esc> to switch to the POST screen and the boot process will
continue until the end of POST.
• Pressing <F2> to enter Setup.
• Pressing <F12> to enter Boot Menu.
• Whenever POST detects a non-terminal error, it switches to the POST screen
near the end of POST, just prior to prompting for a password.
• If the BIOS or an option ROM request keyboard input, the system switches
over to the POST screen with prompts for entering the information. POST
continues from there with the regular POST screen.
3.3

Boot Block

The Flash ROM used in many systems today offer the customer the advantage of
electronically reprogramming the BIOS without physically replacing the BIOS
ROM. This advantage, however, does create a possible hazard: power failures or
fluctuations that occur during updating the Flash ROM can damage the BIOS
code, making the system unbootable. To prevent this possible hazard, many Flash
ROM include a special non-volatile region that can never be erased. This region,
called the boot block, contains a fail-safe recovery routine. If the boot block finds
corrupted BIOS, it prompts the end user to insert a diskette, from which it loads
several files that replace the corrupted BIOS on the Flash ROM with an
uncorrupted one.
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