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.
ESD
Electrostatic discharge.
file
Any group or collection of related information stored
in memory. To add data to a file or to read data from a
file, the program must access the file by its file name.
flash EPROM
A type of erasable programmable read-only memory
that can be erased and reprogrammed electronically
while installed in a PTC.
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).
GND
Ground.
hardware
Equipment used in conjunction with programs or
data communication. Contrast with
host
computer
A personal computer or mainframe that receives and
processes data from PTCs.
Hz
Hertz. A unit expressing frequency in vibrations per
second.
interface
The connection between two devices, defined by
common physical characteristics, signal
characteristics, and signal meanings.
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