Epson EPL-8000 User Manual page 241

Interface Specifications
Signal
RS-232C RS-422 Direction
Pin
20 DTR
Although RTS, CTS, DTR, and DC0 are designated as RS-232C signals, they
can also be used when RS-422 is selected with SelecType.
Appendix A
A-14
Data terminal ready. This pin indicates
OUT
whether or not the printer is ready to
receive data. If the printer ready protocol
is not selected, this pin is always high
(the printer is ready to receive data). If
the printer ready protocol is selected, the
printer can accept data when the pin
level is high and cannot accept data
when the pin level is low. When the DTR
signal goes low, the host computer must
stop sending data within 128 characters.
Can be set high or low with SelecType.
Description