POST BIOS CMOS ROM
POST
Power
On
Self
Test
What happens in POST?
Tells your components to test itself. The
programing will then launch its own appliance to
test itself.
Disclaimer- POST is only as good as the
components manufactures make it.
BIOS
Basic
Input
Output
Service
BIOS Task
Supports hardware that never changes,
Example Internal speaker controller and
Keyboard controller
Supports hardware that might change from time to
time
Any removable component on your computer
CMOS
Complementary
Metal-oxide
Semiconductor
BIOS VS CMOS
Are they not the same thing?
NO but!
CMOS
CMOS stores all of the data that is read by the
BIOS.
The CMOS does NOT store programs. CMOS
only stores data.
ROM
Read
Only
Memory
ROM VS RAM
ROM has two very different characteristics
Nonvolatile memory - information store on
memory does not get erased when computer
turns off.
Once you write a program to ROM you cannot
change it.
Flashing ROM VS ROM
Older style
Cannot be flash
Newer style ROMs or Flash ROM
Can be Flash it is call "Flashing the ROM"
Why ROM?
CMOS
BIOS
POST
Devices
ESD
 http://videos.totalsem.com/video/4