GVC SL5598, Руководство пользователя

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Shadow
Software that resides in a Read-Only Memory (ROM) chip on a device is called
firmware
. The Award BIOS permits
shadowing
of firmware such as the system BIOS,
video BIOS, and similar operating instructions that come with some expansion
peripherals, such as, an SCSI adapter.
Shadowing copies firmware from ROM into system RAM, where the CPU can read it
through the 16-bit or 32-bit DRAM bus. Firmware not shadowed must be read by the
system through the 8-bit X-bus. Shadowing improves the performance of the system
BIOS and similar ROM firmware for expansion peripherals, but it also reduces the
amount of high memory (640 KB to 1 MB) available for loading device drivers, etc.
Enable shadowing into each section of memory separately. Many system designers
hard-wire shadowing of the system BIOS and eliminate a System BIOS Shadow option.
Video BIOS shadows into memory area C0000-C7FFF. The remaining areas shown on
the BIOS Features Setup screen may be occupied by other expansion card firmware. If
an expansion peripheral in your system contains ROM-based firmware you need to
know the address range the ROM occupies to shadow it into the correct area of RAM.