Sharp PC-1211 Service Manual page 14

14
Pin No. Signal name In/Out
Description
12 R/VI
Out RAM Data Read/Write signal
During display: High
During read-in: Turns momentarily low-- - - - - - -
13 DI04 In/Out
Data Bus (for data transaction between RAM and display chip)
14 DI03 In/Out
During display: High
lS DI02 In/Out
During read-in: Turns low--l[lllll
16
DIOl
In/Out
17 B8b Out
Address Bus (for address designation of the display chip)
18
B7b Out
During display: Bl b=high, B2B=low, B3b=low, B4b=low,
19 B6b Out
BSb=high, B6b=high, B7b=low, B8b=low
20 BSb Out
During read-in: Turns momentarily high
21
B4b Out
.
______
/
22 B3b Out
23 B2b
Out
24 Blb Out
2S HA Out
Display signal (Common signal counting pulse)
.ruu Being generated during displaying
--10.Smst--
26 DISP Out
Display command signal
During display: High
During execution: Low
27 VM In
LCD display voltage (Intermediate voltage of the segment
signal)
28
VA
In
LCD display voltage (High side voltage of the segment signal)
29
GND
In
Supply voltage (OV)
30
H4 Out LCD common signals (backplate)
31
H7
Out
32 H3 Out
33 H6 Out
34 H2 Out
3S HS Out
36
Hl
Out
37
VDISP
In
LCD display voltage (Low side voltage of the common signal)
38 VB
In
LCD display voltage (Low side voltage of the segment signal)
39 Sl6 Out
Busy signal to the CPU I (High during the execution in the
CPU II)
During display: Low /
Depression of key causes it momentarily high.
40 SIS Out Record signal to the cassette tape and print data.
41
Sl4 Out Remote signal to the MT.