Technical 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.

ON LINE SLCT IN (Indicator)

o n )

on

line

Low (Sw.

 

 

2-1/

 

 

i n t e r f a c e )

on

line

High

on

line

High

off

line

High/Low

 

 

(no effect)

 

 

 

 

 

 

DC1/DC3

ERROR

BUSY

ACKNLG

Printing

(Data

 

 

 

 

(Disabled/

on/off

 

 

 

 

enabled)

control)

 

 

 

 

 

DC1/DC3

High

High/Low

Pulsed

ea.

Enabled

(no effect)

 

 

char.

 

(normal

 

 

 

 

 

cond.)

DC1

High

High/Low

Pulsed ea.

Enabled

Recv’d

 

 

char

 

 

DC3

High

High/Low

Pulsed

ea.

Disabled*

Recv’d

 

 

char.

 

 

DC1/DC3

Low

High

Not

 

Disabled

(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.

6-8 Technical Specifications