Table of Contents
Advertisement
16.5 Glossary of selected terms
A
Analoque loopback
A local test thal evaluates the internal operation of the modem.
Data is
modulated and demodulated before it is looped back to DTE.
Analoque transmission
Transmission of a continuously variable signal. The electric signal from a
microphone as a resull of human speech is an example of an analogue signal.
The telephone network was designed to transmit voice in analogue form.
ASCII
American Standard Code for Information interchange. The normal character set
used for data entry and transmission.
Asynchronous
During asynchronous data transmission the time interval between the separate
characters can vary. Slart and stop bits are added for synchronisalion.
AT_
Attention code.
This is used at the commencement of Hayes standard command strings.
Baud
Unit used for measure of modulation speed, i.e. the number of signal
modulations per time-unit. (Not the same as bit per second).
Binary
A binary character, 0 or 1. Having a value of zero or one. All data stored ina
computer is stored as a combination of ones and zeroes.
Bit
Contraction of binary digit. This is the smallest unit of information in a binary
system. A bit represents a one or a zero condition.
Bit mapped
A register used to store information that controls the register modem. Each bit
can represent an on or an off condition for a specified function, or more bits can
be grouped if several options exist.
A group of 8 bits.
ITT
Comité Consultatif International Telegraphique el Telephonique. (The
international consultative council for telephone and telegraph). This
organization has changed name to ITU.
LZTR104006 R1.00
1 6-9
Zat 14.4/14.4-7 and 19.2/19.2-7
Advertisement
Table of Contents
