ZyXEL Communications U-90E, Руководство пользователя

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U-90E Data/Fax Modem
Glossary
H
Stop bit : In asynchronous transfers, every character is terminated by one or two stop bits which show
where a character ends.
Synchronous : In synchronous transfer, a dedicated control signal line transmits a clock signal which
paces the transmitted data. In highspeed connections, the transfer between two modems is always
synchronous, even if the DCE to DTE connection is asynchronous.
T.30 : A standard for fax transfers.
TAE6 : A standard for a telephone wall outlet used in some countries, particularly in Germany.
ter : Old French word for three.
Terminal equipment : A computer running terminal software is used as terminal equipment in modem
connections.
Terminal program : A program which emulates the operation of a hardware terminal on a computer's
screen and keyboard.
Token : A token is a reencoding of information in less bits; basically an abbreviation.
Transfer mode : Data can be transferred either synchronouosly or asynchronously.
Transfer rate : The speed at which the data bits are effectively transferred.
UART : Universal Asynchronous Receiver and Transmitter; a special IC chip which controls the serial port.
Different models are available for PCs. Models with an internal buffer usually allow higher transfer rates.
V. : The ITU-TSS V. - standards describe data transfer via telephone lines.
Western jack : Telephone wall outlet connector used in the USA and other countries.
X. : The ITU-TSS X.-standards describe data transfer in public data networks.
XModem : A widely used, though somewhat aged, file transfer protocol. The use of 128 byte data blocks
severely limits the achievable throughput.
XON/XOFF : Software flow control. The data flow is stopped by sending ASCII character Control-Q (dec.
17; hex $11) and restarted by Control-S (dec. 19; hex $13).
YModem : A file transfer protocol which uses data blocks of 1 Kbyte and transfers filenames and more than
one file in one transfer.