CMOS(Complementary Metal-Oxide-Semiconductor) A type of integrated circuit design known for its low power consumption. 12h - IBMInternational Busiuness MachinesInternational Busiuness Machines) A hardware, software and other service technology company founded in 1911. - HARD DISK DATA
Notes: A PCIBM PC with a single type 2 (20 Mb ST-225) hard disk will have 20h in
byte 12h
some PCs utilizing external disk controller ROMs will use type 0 to
disable ROM(Read-Only Memory) A memory for program storage which may not be changed by the program as it runs. BIOS(Basic Input/Output System) A set of standardized calls giving low-level access to the hardware. The BIOS is the lowest software layer above the actual hardware and serves to insulate programs (and operating systems) which use it from the details of accessing the hardware directly. (e.g. Zenith 248 with Plus HardCard).
Bitfields for IBMInternational Busiuness MachinesInternational Busiuness Machines) A hardware, software and other service technology company founded in 1911. hard disk data:
Bit(s) Description (Table C0014)
7-4 First Hard Disk Drive
00 No drive
01-0Eh Hard drive Type 1-14
0Fh Hard Disk Type 16-255
(actual Hard Drive Type is in CMOS RAMA small amount (typically 64 or 128 bytes) of memory in the system's real-time clock chip that is preserved by the clock's battery and is used for storing configuration information. See also Real-Time Clock. 19h)
3-0 Second Hard Disk Drive Type
(same as first except extrnded type will be found in 1Ah).