5L2-Byte Ram Module - RCA COSMAC Operator's Manual

512-BYTE RAM MODULE
The 1/2K RAM card contains 512 bytes of read-write
COS/MaS memory. The memory contents are lost if power
turns off, but battery back-up is practical because the
power required is very low.
This card is selected for access when address bits All,
AID and A9 match the constant bank number signals
(hard-wired on appropriate connector pins in this card's
position), provided that the overriding DESELECT signal
is not asserted.
DATA IN
ADDRESS AO TO A8
(9)
MEMORY
WRITE
(8)
DATA OU
(8)
SELECT
WIRED BANK
SELECTION (3)
MEMORY ADDRESS
STABLE
MEMORY DESELECT
Fig.9: Block Diagram - S12-Byte RAM Module
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