display The LCD screen on the front of the PTC. It shows data entered
into the PTC and warning prompts.
DSR Data set ready signal. The modem sends DSR to the attached
device to indicate that the modem is connected, on, and ready.
DTE Data terminal equipment. A device comprising the data source.
For example, the host computer.
DTR Data terminal ready signal. The signal sent by the terminal
device to the modem to indicate that the terminal is ready for
transmission.
function key A key on the PTC’s keyboard that is defined by an application to
perform a specific task. When pressed, a function key executes a
certain function (for example, ENTER, END, ON/OFF).
hardware Equipment used in conjunction with programs or data
communication. Compare with software.
host
computer A personal computer or mainframe that receives and processes
data from PTCs.
keyboard
overlay The plastic label that lies on the PTC keyboard, identifying the
function key definitions.
LCD Liquid crystal display. The PTC-860’s display is of this type.
LED Light-emitting diode.
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.
nickel-cadmium
battery pack A type of rechargeable battery used to power the PTC and some
of its accessories.
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.
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