Epson PX-8 Technical Manual page 102

2.8.3 X-Y Display Control Timing
LP
XSCL
E
Approx.3.25tLsec
XECL
YSPU
YSCL
Approx. 285tLsec
"APprox. 1 30 tLsec (3.25 tLsec x 40)
Total 120 pulses
~Corresponds
to 15 XSCL pulses.
Fig. 2-80
REV.-A
..
Four displayed dots (or four data bits), are transferred by a single XSCL pulse. (480 dots
=
4 x 120
x SCL pulses). The data bits for one entire dot line in the Y direction, are transferred in a duration
of 130 f.ls.
A pulse signal LP is generated at the came frequency as the XSCL pulse signal. This signal out-
puts the Y-line data output signal YDOO when it is activated. This causes the Y-line drive position
to be advanced by one dot to designate the next dot line.
2-78