Symbol PTC-870IM User Manual page 65

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.
network
An interconnection of computer systems, terminals,
and data communication facilities.
prompt
Messages shown by the PTC that guide the operator
through the steps of the application program.
Prompts are different for different programs.
PTC
Portable Tele-Transaction Computer. A programmable
device used to collect, store, and transmit data.
RAM
Random access memory. In a PTC, RAM chips store
program files and data entered by the operator.
RAMdisk
A volatile disk simulated in RAM. It is treated by the
MS-DOS operating system in the same way as a
physical disk drive.
resume
A feature of the PTC-870IM that returns you to the
point where you were in your application program
when the PTC was turned off or went to sleep. See
sleep.
RF
Radio frequency.
RI
Ring indicate signal. RI alerts a modem to a call
waiting on the attached telephone line.
ROM
Read-only memory. In a PTC, ROM chips contain the
operating system and the application program.
ROMdisk
A non-volatile disk simulated in ROM. It is treated by
the MS-DOS operating system in the same way as a
physical disk drive.
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