Interface Specifications

Signal

-232C RS-422

Direction

Description

Pin RS

20

DTR

OUT

Data terminal ready. This pin indicates

 

 

 

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.

 

 

 

 

Although RTS, CTS, DTR, and DC0 are designated as RS-232C signals, they can also be used when RS-422 is selected with SelecType.

A-14Appendix A