IBM 5150 Technical Reference page 284

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.
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