Page 57 - The Illustrated Dictionary of Electronics

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42 assemble • astrionics

Symbols for ASCII teleprinter code assembly program The program that operates on
a symbolic-language program to produce a ma-
chine language program in the process of assem-
First Last three signals bly. Also called assembler.
four assembly robot A form of industrial robot that puts
signals 000 001 010 011 100 101 110 111 hardware together. Such a robot is generally a
component of an automated integrated manufac-
0000 NUL DLE SPC 0 P / p turing system (AIMS). The robot can do repetitive
work at high speed and precision for long periods
0001 SOH DC1 ! 1 A Q a q
of time.
0010 STX DC2 " 2 B R b r
assign To reserve part of a computing system for a
0011 ETX DC3 # 3 C S c s
specific purpose, normally for the duration of a
0100 EOT DC4 $ 4 D T d t program run.
0101 ENQ NAK % 5 E U e u assigned frequency The radio carrier frequency or
0110 ACK SYN & 6 F V f v band of frequencies designated for a transmitting
0111 BEL ETB ' 7 G W g w station by a licensing authority. Also see RADIO
1000 BS CAN ( 8 H X h x SPECTRUM.
1001 HT EM ) 9 I Y i y associative memory Computer memory in which
locations are identified by content, rather than by
1010 LF SUB * : J Z j z
specific address.
1011 VT ESC + ; K [ k {
assumed decimal point A decimal point that does
1100 FF FS , < L / l /
not occupy an actual computer storage space,
1101 CR GS – = M ] m } but is used by the computer to align values for
1110 SO RS . > N n ~ calculation; the decimal point is assumed to be at
1111 SI US | ? O - o DEL the right unless otherwise specified.
astable Having two temporary states; BISTABLE.
astable circuit A circuit that has two unstable
ACK: acknowledge FF: form feed
states, and whose operation is characterized by
BEL: bell FS: file separator
alternation between those states at a frequency
BS: back space GS: group separator
determined by the circuit constants.
CAN: cancel HT: horizontal tab astable multivibrator A free-running multivibra-
CR: carriage return LF: line feed tor. The common circuit uses two bipolar or field-
DC1: device control no. 1 NAK: do not acknowledge effect transistors, their inputs and outputs being
DC2: device control no. 2 NUL: null cross coupled. Conduction switches alternately
DC3: device control no. 3 RS: record separator between the two.
DC4: device control no. 4 SI: shift in astatic 1. Without fixed position or direction. 2. In
a state of neutral equilibrium.
DEL: delete SO: shift out
astatic galvanometer A galvanometer with a mov-
DLE: data link escape SOH: start of heading
able element consisting of two identical magne-
ENQ: enquiry SPC: space
tized needles mounted nonparallel on the same
EM: end of medium STX: start of text suspension. Each needle is surrounded by a coil.
EOT: end of transmission SUB: substitute The coils are wound in opposite directions, and
ESC: escape SYN: synchronous idle are connected in series to the current source. A
ETB: end of transmission US: unit separator large permanent magnet provides the field
block VT: vertical tab against which the needle assembly rotates. The
ETX: end of text instrument functions independently of the geo-
magnetic field.
astatine Symbol, At. A radioactive elemental halo-
gen produced from radioactive decay. Atomic
symbolic program language into a machine (bi- number, 85. Atomic weight, 210. Formerly called
nary) language program by substituting opera- alabamine.
tion codes and addresses. A station One of the two stations in the transmit-
assembly 1. A finished unit that can be either a ting system of LORAN (long-range navigation).
practical working model or a dummy, a proto- astigmatism A focusing fault in a cathode-ray
type, or a final model; an integrated aggregation tube (CRT), in which electrons in different axial
of subunits. 2. A low-level computer source-code planes focus at different points.
language that uses crude mnemonics that are ASTM Abbreviation for American Society for Testing
easier to remember than the machine-language and Materials.
equivalents. astrionics The design, production, and application
assembly language A source code that uses of electronic devices and systems for use in space
mnemonic instructions. (See ASSEMBLY, 2.) vehicles and space navigation.