modem
Modulator-demodulator. A communication
device that converts serial digital data from
a transmitting device to a signal suitable for
transmission over a telephone line and then
reconverts the signal to serial digital data for
the receiving device.
MS-DOS
Microsoft Disk Operating System.
one-way
communication
Transport of information from one device to
another without interruption. In one-way
communication, the receiving device cannot
respond directly to the sending device.
PCTCOS
A file download utility program.
prompt
Words or symbols shown on the PTC’s or PC’s
display to guide the operator through the steps
of an application. Prompts are defined in the
application program.
PTC
Portable Tele-Transaction Computer. A pro-
grammable, battery-powered, hand-held device
used to collect, store, and transmit data.
RAM
Random access memory. In a PTC, RAM chips
store the program’s files and data entered by
the operator.
RAMSaver
Telxon’s version of Microsoft’s MS-DOS 3.2
that has been modified to perform MS-DOS
functions on a PTC.
RI
Ring indicate signal. RI alerts a modem to a call
waiting on the attached telephone line.
RS-232
An Electronic Industries Association (EIA)
standard that defines the connector, connector
pins, and signals used to transfer data serially
from one device to another.
RTS
Request-to-send signal. RTS initiates the data
transmission sequence on a communication line
between a modem and a terminal device.
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