Epson LX-HOO, Техническое руководство

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REV.-A
CMOS
The is a 8K-byte CMOS static RAM. The has low power consumption, and its input/output
level is compatible with the ICS. Figure A-8 shows the pin diagram, and Figure A-9 shows
a block diagram for the static RAM.
●
Features
●
Capacity of 8192 words X 8 bits
.
●
Power 5V DC
●
28-pin DIP Switch
●
Functions
●
AO - Al 2
●
w
●
-
●
●
DO - D7
●
NC
AO
At
A3
A4
Input address
Write enable
Output enable
Chip select
Input/Output data
No connection
I
X X 6
6
Logic
A ?
A 6
A 4
A 3
A 2
D 2
D 3
Vss
L-
5
2 0 6
7
8
10
-
13
14
4 C
25
24 A 9
23 All
20
19 D7
17 0 5
16 D4
Fig. A-8. Pin Diagram
02 03
D
4 05
Fig. A-9. Block Diagram
Table A-6. Truth Table
- DATA
MODE
H x
— — —
High impedance Wait
—
L
— — —
High impedance Wait
L H x L Stable
Input data Read
L H L H Stable Output data Write
L H H H Stable
High impedance
Output disable
NOTES: 1. X = HIGH or L O W
2. – =
HIGH, LOW or High-impedance
A-9