Epson LX-80, Operating Manual

Page: 178 / 193

Appendix I
The Parallel Interface
Th e L X - 80 printer uses a parallel interface to communicate w ith the
co mpu ter; this appendix describes it .
Co nn e cto r pin assignments and a description of respective int e r face
sig n a l s a r e s hown in Table 1-1 .
Signal Return
Signal
Direc-
Description
Pin
Pin
tion
1 19 STROBE IN STROBE pulse to read data in . Pu lse
width must be more than 0.5 micro -
seconds at the receiving termina l .
2
20
DATA1 IN These signal represent information of
3
21 DATA2 IN the 1st to 8th bits of parallel data,
4 22 DATA3 IN respectively. Each signal is at HIGH
5 23 DATM IN level when data is logical 1 and LO W
6
24 DATA5 IN when it is logical O.
7 25 DATA6
IN
8 26 DATA7 IN
9 27 DATA8 IN
1 0
28 ACKNLG
OUT
Approximately 12-microsecond pul se .
LOW indicates that data has been
received and that the printer is rea
dy
to accept more data .
1 1 29 BUSY OUT A HIGH signal indicates that the pr int-
er cannot receive data . The signal
goes HIGH in the following cases :
1) During data entry .
2) During printing .
3) When off-line .
4) During printer-error state .
12 30 PE OUT A HIGH signal indicates that the pr int-
er is out of paper .