4. Mega-Midget Racer Features
MC68030 Microprocessor (CPU):
The
Mega-Midget Racer
utilizes an MC68030 microprocessor in an asynchronous design
operating at clock frequencies of 20, 25 and 33 MHz, or any speed in between. A single crystal
oscillator defines the clock speed of the system: no jumpers or special parts are required.
Replaces Amiga’s MC68000 CPU:
The
Mega-Midget Racer
is a direct, plug-in replacement for the MC68000 CPU in the Amiga
A500 or Amiga A2000. To assure 100% software compatibility, the MC68000 is re-installed
on the
Mega-Midget Racer
accelerator and becomes software and hardware selectable.
Optional High-Speed, 32-Blt, 512k Byte SRAM Area:
Sockets are provided on the
Mega-Midget Racer
for 512K Bytes of 32-bit static random access
memory (SRAM). This is facilitated with four user installable 128K x 8-bit SRAM modules or
monolithic chips. If the user desires, the Amiga’s ROM kernel can be copied into and executed
out of this memory area. Special hardware allows this to be accomplished with out the use of the
MC68030’s MMU, which leaves it available for use by other software. The 512k bytes of
SRAM, or the 256k bytes remaining after the ROM is loaded, can be added to the general memory
of the Amiga operating system.
Full 32-bit Expansion Bus:
B u i l t i n c o n n e c t o r s a n d c i r c u i t r y p r o v i d e s f u l l 3 2 - b i t w i d e d a ta a n d a d d r e s s s u p p o r t f o r
additional hi-speed memory and other I/O devices in 8, 16 and 32 bit configurations.
Special Cache Control Logic:
A special cache control PLD (programmable logic device) provides for safe caching of both
instructions and data. The original data cache environment includes the system ROM and any
32-bit memory. The 16-bit RAM in the Amiga may or may not be safe for data caching. If your
system meets certain requirements, then most of your 16-bit RAM may be added to the data
cache environment by installing a new cache control PLD. Contact CSA for more information.
Optional MC68881/MC68882 Floating-Point Co-Processor:
A co-processor socket is provided to support an MC68881 or MC68882 floating-point unit
(FPU) at frequencies from 20 MHZ to 50 MHz. The FPU can be clocked by the same crystal
oscillator as the MC68030 CPU, or by a second, higher frequency oscillator. Note: CSA
recommends that the FPU be operated at a frequency that is the same as or higher than the
frequency of the MC68030 CPU.
Surface Mount Technology and Other Features:
All components on the
Mega-Midget Racer
that are not user installable are surface mounted to
enhance reliability and conserve space. Supply power is provided through the MC68000 socket
(5.0 VDC @600mA) and optionally through an extra power connector which is compatible with
the Amiga’s disk drive power cables. Physical support is provided through the MC68000 socket
pins and optional plastic stand-offs. The operating temperature range is 0-70 °C.
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