Double-Digit Keying
Pressing two number keys in rapid succession to access a page in a videotex system. The first number accesses an intermediate index (see Intermediate Page) which in turn accesses the page. See also
Dumb Terminal
Terminals that do not contain an intelligent microprocessor and usually send data one character at a time.
Duplex Transmission
Independent, simultaneous,
E
EBCDIC
Extended Binary Coded Decimal Interchange Code. An eight bit code used primarily by IBM equipment.
Echo
The
Echoplex
Method of verification of transmitted data by echoing the characters transmitted back to the source device for verification. Echoplex is sometimes called remote echo and, erroneously, half- duplex.
EEPROM
Electronically Erasable Programmable Read Only Memory.
EIA
Electronic Industries Association. Organisation in the USA that sets standards for the functional characteristics of electronic interfaces.
Electronic Mail
A means by which users of a particular bulletin board or videotex system can send messages to other users of that system. Some
E-MAIL
See Electronic Mail.
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