Epson LQ-2550 Technical Manual page 101

REV.-A
From
CPU
To
Host
From
INPUT BUFFER
VACANT ARE~
s e t Inltlal v a l u e s .
EBUSY--L-
Send X-ON (llH).
n e data twrrer
v a c a n t 8rea reach
-
EBUSY= H
Send X-OFF ( 13H ).
recoin I ze and
Host
I i ne data butrer
v a c a n t a r e a reach
Figure 2-49. RS-232C Serial Interface Circuit Operation
INITIAL IZE
H
E BUSY
L
[
SPACE
MARK
SPACE
SPACE
Figure 2-50. RS-232C
I
-
( DTR-MARK ) .
I
I
I
I
X-ON
OATA
I
8K byte
Data Transmission Timing
2-54
OPERATION
I
X-OFF X-ON