Epson PX-8 - V-Ram6117

REV.-A
7.13 V-RAM6117
The 6117 is a 2048 x 8 bit C-MOS static RAM. This computer has three 6117 RAMs, totalling a
6KB capacity, which are used mainly as LCD memory. All the V-RAMs are backed up by the bat-
tery and can hold stored data if power is turned off. The RAMs are accessed via the slave CPU
6303. A functional block diagram of V-RAM circuitry is illustrated in Fig. 7-30.
Fig. 7 -30 is a functional block diagram of 611 7 .
Al
...
A2
Vcc
A3
\j
-
A4
Row
Memory Matrix
GND
A5
Decoder
128" 128
A6
r-
A7
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~
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I
"
1/01
1~
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Column I/O
CE2
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Input
Cplumn Decoder
I I
Data
I I
Control
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I I
I I
I I
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1/02 ,...
l
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I
A7 AS A9 Al0
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f
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CEl
WE
Fig. 7-30 6117 V-RAM Block Diagram
7-61