CSA Mega-Midget Racer, Руководство пользователя

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8. CSA Mega-Memory™ 32-bit DRAM Daughter-Board
General Features
The available 32-bit memory of the Mega-Midget Racer accelerator is
increased by the use of the CSA Mega-Memory DRAM daughter-board, which
is socketed for 1, 2, 4, or 8 megabytes (MB) of 32-bit wide DRAM. The
DRAM is accessed over a high speed 32-bit bus, which connects the
accelerator to the DRAM daughter-board. A state-of-the-art, Very Large
Scale Integration (VLSI) controller chip and specially designed circuitry
achieve high access speeds. Special CSA configuration software (supplied
with the board) installs the memory and optimizes its operation for best
performance.
The CSA Mega-Memory DRAM daughter-board is specifically design for, and
w i l l o n l y w o r k w i t h , t h e C S A M e g a - M i d g e t R a c e r a c c e l e r a t o r. T h e
daughter-board attaches to connectors located on the right-side edge of
t h e a c c e l e r a t o r f o r i n s ta l l a t i o n c o m p l e t e l y i n s i d e t h e A m i g a s e r i e s o f
computers. No external connections are required.
CSA’s innovative design permits the use of readily available, low cost,
user installable DRAM chips. The CSA
Mega-Memory DRAM daughter-board
is jumpered to select 1MB or 2MB of RAM using 256kx4 DRAM chips and
4MB or 8MB using 1Mx4 DRAM chips. Both sizes of DRAM come in the same,
easy to install, 300mil wide, 20-pin DIP chip packages.
The MC68030’s Memory Management Unit (MMU) may be used to copy the
Amiga’s operating system ROM kernel into the 32-bit DRAM memory for
those users who do not have CSA’s 32-bit SRAM installed on the
Mega-
Midget Racer accelerator. If SRAM is installed, the user may choose to
enable the SROM feature, which puts the Amiga ROM kernel into the SRAM
without the use of the MC68030’s MMU. This is accomplished through
special hardware on the
Mega-Midget Racer and leaves the MMU free for
use by other software.
A special version of the CSA Mega-Memory DRAM daughter-board is used
for the Amiga 2000 in order to provide adequate space for the installation
of popular video accessories into the internal video slot.
Preparing the CSA Mega-Memory DRAM Daughter-Board for Installation
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