Interface Specifications

Printing enabled/disabled signals and control conditions

The table below shows the relationship between printing being enabled or disabled, and the on-line/off-line condition, the printer select signal (SLCT IN), and the receipt of data on/off control character, DC1/DC3.

 

 

 

 

 

 

 

 

 

 

 

 

Printing

On-line

SLCT

IN

DCllDC3

ERROR

BUSY

ACKNLG

(Indicator

 

 

 

(Data on/off

 

 

 

 

 

 

(Disabled/

on)

 

 

 

control)

 

 

 

 

 

 

enabled)

 

 

 

 

 

 

 

 

 

 

 

 

 

ON-LINE

Low

 

 

 

 

 

 

 

 

 

 

 

 

(J9/

 

 

DClIDC3

High

High/Low

Pulsed

ea.

Enabled

 

interface)

(no

effect)

 

 

 

char.

 

 

(normal

 

 

 

 

 

 

 

 

 

 

 

 

cond.)

 

 

 

 

 

 

 

 

 

 

 

 

 

ON-LINE

High

 

 

DC1

Recv’d

High

High/low

Pulsed

ea.

Enabled

 

 

 

 

 

 

 

 

 

char.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ON-LINE

High

 

 

DC3 Recv’d

High

High/Low

Pulsed

ea.

*Disabled

 

 

 

 

 

 

 

 

 

char.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

OFF-LINE

High/Low

DCl/DCB

Low

High

Not

 

 

Disabled

 

(no

effect)

(no

effect)

 

 

 

generated

 

 

 

 

 

 

 

 

 

 

 

 

 

 

*Even though printing is disabled, data characters are received and acknowledged, since the printer is looking for another DC1 character, which would allow it to resume printing.

Serial interface

The LQ built-in serial interface is an RS-232C asynchronous interface with the following characteristics:

Data format 1 start bit

Data word length: 8 bits Odd, even or no parity 1 stop bit

Signal level

Mark (1) - 3V to - 27V

Space (0) + 3V to + 27V

Band rate

300, 1200, 4800, 9600 BPS

8-9