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Glossary
5.375 x 8.375 ver 2.4.0
synchronous:
Having a constant time interval between successive
bits, characters or events. Synchronous data transmission
requires both the sending and receiving devices to use special
synchronizing characters to correct variations in timing between
the devices. See also
asynchronous.
T
Test function
: When normal communication is not possible, this
function checks the modem, personal computer, and telephone
lines to determine if they are normal.
Tone dialing
: A dialing method that uses tones instead of pulses to
generate a telephone number. Generally associated with push-
button phones, although some push-button phones can be
connected to pulse lines.
U
upload:
To send a file to another computer through a modem. See
also
download
.
UART:
Universal Asynchronous Receiver Transmitter is the circuit
interface between the modem and computer. It receives serial bit
data from the modem and converts it into bytes for the computer;
and it converts byte data from the computer into bit data for serial
communication.
X
XON/XOFF flow control:
A protocol used by devices receiving
data. It uses two signals: transfer ON and transfer OFF. The
signals are controlled by software.