IBM 5150 Technical Reference

multiprogramming. (1) Pertaining to the concurrent execution of
two or more computer programs by a computer. (2) A mode of
operation
that provides for the interleaved execution of two or
more computer programs by a single processor.
~ n. Prefix nano; 0.000000001.
NAND. A logic operator having the property that if P is a
statement,
Q is a statement, R is a statement, ... , then the NAND
of P, Q ,R, ... is true if at least one statement is false, false if all
statements are true.
NAND gate. A gate in which the output
is 0 only if all inputs are
1.
nano (n). Prefix 0.000 000 001.
nanosecond (ns). 0.000000001 second.
~ negative true. Synonym for active low.
negative-going edge.
The edge of a pulse or signal changing in a
negative direction. Synonymous with falling edge.
non-return-to-zero change-on-ones recording (NRZI). A
transmission encoding method in which
the data terminal
equipment changes the signal to the opposite state to send a
binary
1 and leaves it in the same state to send a binary o.
non-return-to-zero (inverted) recording (NRZI). Deprecated term
for non-return-to-zero change-on-ones recording.
NOR. A logic operator having the property that if P
is a
statement,
Q is a statement, R is a statement, ... , then the NOR of
P, Q, R, ... is true if all statements are false, false if at least one
statement
is true.
NOR gate. A gate in which the output is 0 only if at least one
input is
1.
Glossary-23

IBM 5150 Specifications

General

Processor	Intel 8088
Clock Speed	4.77 MHz
RAM	16 KB - 256 KB
Manufacturer	IBM
Model	5150
Release Year	1981
Storage	5.25-inch floppy drives
Graphics	MDA or CGA
Operating System	IBM PC DOS
Ports	Cassette, keyboard
Expansion Slots	5