Symbol PTC-870IM, Руководство пользователя

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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.
RS-422
An Electronic Industries Association (EIA) standard
that defines the connector, connector pins, and signals
used to transfer data serially from one device to
another. RS-422 differs from RS-232 in providing a
faster transmission speed and lower level of noise for
communication over long distances.
RTS
Request-to-send signal. RTS initiates the data
transmission sequence on a communication line
between a modem and a terminal device.
RXD
Receive data signal. RXD indicates that a device is
currently receiving data.
signals
Electronic impulses that transmit data from one
device to another.
sleep
A power-saving feature of the PTC-870IM. The
PTC is capable of slowing or turning off portions
of its electronics to conserve power. Sleep occurs
automatically when the PTC has not been used for
a predetermined period of time.
software
A stored program or set of programs that is loaded
into RAM for execution. Contrast with
hardware .
Software
Development Kit
A set of diskettes containing libraries of C programs
and Telxon utilities to be used for programming
pen-based applications for the PTC.
spread
spectrum
A radio communication technology that distributes
an RF signal over a wide range of frequencies for
transmission; it then “despreads” the signal to the
original frequency range at the receiver.
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