that operate like a bank of capacitors. The cells are
capacitor type circuits; a charged cell equals a logic 1
while a discharged cell equals a logic 0 Each cell
consists of a MOS transistor and a tiny capacitor.
READ-ONLY MEMORY (ROM)— ROMs are
used for various memory applications, such as fixed
program storage, look-up tables, and code conversions.
The programs on the ROM are actually more hardware
than software (firmware). The contents of the ROM
addresses can be used over and over again without
alteration. The primary use of a ROM allows the
computer to perform its I/O operations.
PROGRAMMABLE READ-ONLY MEMORY
(PROM)— A PROM is a programmable ROM. Once
programmed it acts like a ROM. It maybe erasable or
nonerasable.
Learn all you can about the memories used in the
computers you maintain.
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