Compuprint 4051 Guida Utente

 C-17

 

The following table lists the RS-422/A serial interface signals::

 

 

 

 

 

T (A)

 

Printer

 

13

 

Transmit.

 

MARK signal is present when
printer is not sending data.

 

T (B)

 

 

14

 

Transmit Return.

 

R (A)

 

Host

 

16

 

Receive.

 

A MARK level is expected when
sender is in idle state.

 

R (B)

 

 

19

 

Receive Return.

 

G

 

 

7

 

Signal Ground.

 

Always connected to the 0 Volt of
the power supply.

 

SHIELD

 

 

1

 

Cable Shield.

 

Optionally connected to the frame
ground of the printer via a suitable
jumper.