IBM LB20 User Manual page 69

host.
RTS/CTS Request To Send / Clear To Send. One of the standards
used by the RS232C protocol for controlling the flow of
data between two communicating devices using handshake
signals. When the host wants to send data to the printer, it
must wait for the printer RTS line to go on. If the printer
RTS line goes off, the host must stop transmission and wait
for it to go on again before sending any data. If the host
input buffer is full, when receiving an incoming message
from the printer, it must turn the printer CTS line off so that
the printer stops transmitting data. To restart
communication, the host turns the printer's CTS line on.
RX Receive
RXD Receive Data
Resident Character permanently available in the printer.
Set
Reversed where characters are printed in white against black.
Stop bit The bit which signals the end of data.
SVT Standard Voltage Temperature
TX Transmit
TXD Transmit Data
Underscore To draw a line under printed characters and spaces.
UL Underwriters Laboratory
Unidirectional print where the printer prints from left to right only.
mode
V Volt
VA Volt Ampere
XON/XOFF A software protocol for controlling the flow of data between
two communicating devices. By sending the XON
(Transmit on) code, the receiving device informs the
transmitter that it is ready to receive data. By sending the
XOFF (transmit off) code, the receiver instructs the
transmitter to stop sending data.
Glossary 7-3