Epson 1000 Reference Manual page 101

DTR-Use this option to turn the printer's ready
communications protocol ON or OFF. You can use DTR (Data
Terminal Ready) protocol in combination with the XON/XOFF
option setting.
Menu/submenu
XON/XOFF-Use this option to turn the XON/XOFF
communications protocol on or off. You can use XON/XOFF
protocol in combination with the DTR option setting.
Menu/submenu
XON/XOFF
ENQ/ACK-This option is available in the Epson GL
emulation only. If you are using another printer emulation,
leave this option set to OFF.
Menu/submenu
DSR-When DSR (Data Set Ready) is OFF, the signal level is
permanently set HIGH, allowing the printer to send data to the
computer. The factory setting is OFF (signal level is HIGH). For
most communications purposes, this option should be set to
OFF. When DSR is ON, data is sent to the computer only when
DSR is HIGH.
Menu/submenu
Available options
ON ) ON or OFF
Available options
ON
Available options
OFF b ON or OFF
Available options
OFF b ON or OFF
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