Orange Micro RAMPAK 4GS - Manual (Page 23)

APPENDIX D: SPECIFICATIONS OF
RAM EXPANSION CHIPS
The technical specifications of the RAM chips used
to expand the memory of the RamPak are as follows:
2 5 6 K x 4 , o n e m e g a b i t , 1 5 0 n a n o s e c o n d ( o r
f a s t e r ) , “ C A S b e f o r e R A S ” r e f r e s h m o d e
D R A M S .
APPENDIX E: GLOSSARY
B A N K : 64K Bytes of memory.
B L O C K : A portion of data 512 bytes in length, as
viewed from ProDos.
B U F F E R : A designated area in RAM where a single
ProDos block is stored if caching is active.
B U F F E R P O O L : A collection of contiguous buffers
used by the cache program to store ProDos blocks.
C A C H E : A storage area in RAM to eliminate disk
access time for data.
C E L L I N T E G R I T Y : The ability of a RAM cell to accept
and retain data, regardless of the data pattern or cell
location. Also see DATA RETENTION.
DATA RETENTION: The ability of a RAM cell to
retain data, without errors, when no memory accesses
occur over a period of time.
DRAM: Dynamic Random Access Memory.
D Y N A M I C C A C H E A L L O C A T I O N : A l l o w s the
program to
allocate buffers from the buffer pool as required
by the system. Additional buffers are automatically allocated
to more frequently used drives.
H I T : An attempt to read a block from disk that has
already been cached, thus finding the data in cache
memory.
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