How can I use this kind of Option BIOS?

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Joined: Thu Aug 07, 2003 11:50 am

I am designing a kind of embended motherboard. Now I have a flash EPROM that is 512KB. I want program the system BIOS and an option BIOS in the chip. The system BIOS is designed by AMI co. . I want the option BIOS to load the operation system 's loader. How can I access the option BIOS.
What does the ROM "shawde" is mean? :P
BIOS Bodhisattva
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Joined: Fri May 03, 2002 10:34 am
Location: Thames Valley, UK

hbxffrm wrote:What does the ROM "shawde" is mean? :P
This bit I know. Executing code from a 150ns (or slower), 8-bit ISA bus ROM is very slow compared to executing from RAM. To speed up execution of the BIOS code, it can be copied to RAM. Using memory management, this area of RAM can be mapped into the address space that was originally used by the ROM, so the code appears in the same place but runs faster. This used to be particularly useful for VGA BIOSes back in the days of DOS.
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