Lcd Unit - Epson PX-8 Technical Manual

REV.-A
2.8
LCD Unit
The LCD unit consists of a driver board (MAP-LD) and a liquid crystal display panel, and provides a
display area of 480 x 64 dots. The display panel is provided with a ratchet which allows adjust-
ment for the optimum view angle. Fig. 2-74 is a control block diagram.
SED 1320 A
"
Slave CPU
/ - -
V
Address/data bus
\
6303
/
~
R/W
I
I /
I /
...
AS (Address Strobe)
I
/
Clock signal
....
I
...
Character
I
/
generator
,
I.
j.,
L ____
\Address/dat~)
RAM
r - -
I
L __
'I
Read/write
I/'
(6 kB)
control
(LINE, LDO)
.......... Q) .::-- . .
..........
""1:
>
0
.-
....
....
....
'Oc:
V-drive control
, 0
,. Xu
~
...........
-~
Supply voltage
~
480 dots
/
~
64 dots
(LCD Unit)
r\
I)
1
Fig. 2-74 LCD Unit Control Block Diagram
The LCD unit is controlled by the slave CPU 6303 as shown in the above block diagram. In the
character mode, the character generator in SED1320 is used for display. In the graphic mode, how-
ever, the data from the 6kB RAM are displayed with all the data bits corresponding to the 480 x
64 display dots (or segments), one to one. In either mode, data are output bit-serially from
SED1320 in synchronization with the X-V drive line signals.
2-73