Epson LQ-2550 Technical Manual page 289

REV.-A
Signal
Pin No.
A l a
37
Al 5
38
39 KANJI
4 0 ALE
41
42 PROG
WR
43
44 RST
Pin No. Signal
1 BAT
2
Pin No. Signal
1 SHLD
3 REDY
13 OLSW
4
6
15
12 AO
8 DO
7
10 D2
9 D3
5 WR
11 LCDCE
14 LOAD
16
CKO
17
DTO
18 + 5
2
Table A-22. CN6 Pin Assignments
Not connected
—
Bank 1
0
ROM OE Signal
o Kanji C.G
Not connected
—
o
Not used
o
Write pulse
o
used
o Not
Table A-23. CN7 Pin Assignments
I
Battery + side (3.0 to 3.3 VDC)
Ground
—
Table A-24. CN8 Pin Assignments
— Pulled down
z
o LED2 ON/OFF "
I
Read status of SW5, SW6, SW8, and SW1 O "'.
I Read status of SW7, SW9, SW1 1, and SW12.
Read status of SW2, SW3, and SW4.
o LCD control driver IC address bit O
o LCD control driver IC data bit O
o LCD control driver IC data bit 1
LCD control driver IC data bit 2
o
o LCD control driver IC data bit 3
o LCD control driver IC write strobe
o LCD control driver IC chip select
Port expander IC parallel data output trigger
o
Port expander IC Serial data transfer clock
o
Port expander IC Serial data
o
+ 5 VDC
o
— Ground
Description
Description
Description
A - 4 4