V-Ram6117 - Epson PX-8 Technical Manual

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 .
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A2
Vcc
A3
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A4
Row
Memory Matrix
GND
A5 Decoder 128" 128
A6
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A7
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Data
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A7 AS A9 Al0
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Fig. 7-30 6117 V-RAM Block Diagram
7-61