25-04-2012, 04:29 PM
BIOS and CMOS
bios and cmos.pdf (Size: 1.24 MB / Downloads: 228)
The Bus
• The external data bus joins the various
parts of the PC together
• The address bus also connects to various
parts
BIOS
• A special kind of program is required to
enable the CPU to talk to other devices
• A ROM chip stores these programs
• These programs are collectively known
as the Basic Input/Output Service
(BIOS)
CMOS Group of Hardware
• Hardware that is common, necessary but
may change
– RAM, hard drives, floppy drives, serial and parallel
ports
– Complementary metal-oxide semiconductor
– Programs are stored on the system BIOS chip,
while the changeable data is stored on a CMOS
chip
CMOS Setup
• The floppy drive, hard drive, and the
date/time settings can be changed using
the standard CMOS setup
• Modern computers provide extra CMOS
settings for memory management,
password and booting options, error
handling, and power management