68000
The internal processor was 32-bit, but externally it used a
16-bit interface. It could address up to 16MB of RAM and execute
three quarters of a MIPS (Million Instructions Per Second) on an
8MHz machine. The Amiga 1000, 2000 and 500 was clocked at
7.14MHz.
Machines that used it
A500 A500+
A600
68008
A cheaper version of the 68000 chip, as used in the Sinclair QL.
It has a 16-bit CPU, but only an 8-bit data bus.
Machines that used it
Sinclair QL
68010
A special version of the 68000 chip designed to multitask. The
processor acts as if it were a number of 68000 processors for each
program running. A few bugs were fixed in the "supervisor" mode. It
was also slightly faster than the 68000 due to slight
modifications.
Machines that used it
Available as an upgrade for A500 owners
68012
Fixed a few bugs in the design. Never used on the Amiga.
68020
A full 32-bit version of the 68000 chip. The full 68020 version
increased the amount of memory usable up to 4 gigabytes. The EC
(Embedded Controller) version present in the A1200 is only able to
use a maximum of 16MB RAM. The chip introduced an instruction cache
to increase the speed of operations. The EC version found in the
A1200 was chosen because it was slightly cheaper as it did not
contain cache memory. Motorola originally designed it to be used in
video and washing machines!
Machines that used it
A1200 Some A500, A500+ and A600
accelerators
68030
An upgraded 68020 chip with a larger cache memory. It also added
a Memory Management Unit (MMU) and Floating Point Unit (FPU). This
allows the computer to use virtual memory. Some accelerators only
fit the EC version of this chip which omits the MMU. The clock
speed had also been increased to a maximum of 50MHz. An FPU has to
be added externally.
Machines that used it
A3000, A4000/030, some A500,
A500+, A600,
CD32 and A1200
accelerators
68040
A vast improvement in speed over the 68030. It contained MMU,
FPU and larger instruction and data caches built-in. The 25MHz
68040 found in many A4000's gives a performance of 19MIPS. Some
A4000 came with a cut down EC version that did not contain the FPU,
whilst the LC (Low Cost) version removed both the MMU and FPU. The
68040 chip is the warmest of the 68k family requiring many
040-based A1200's to be raised slightly to increase
ventilation.
Machines that used it
A4000/040 Some A500, A500+, A1200, and A3000
accelerators
68060
The last in the 680x0 series. This was almost 100 times faster
than the 68000 and three times as fast as the 68040. It had a
number of advancements over the 68040 such as the fully static
design which witched off individual parts of the processor when it
was not in use, saving power and creating less heat. The 50MHz
68060 in a Cyberstorm runs at just under 40 MIPS.
Machines that used it
A4000/60 Some A1200, A4000
accelerators
68070
Not the next generation of processor, but one even slower than
the 68000. Although it is compatible with the 68000, it was made by
Philips not Motorola. The SCC68070 features two serial ports, a
Memory Management Unit (MMU) and a Direct Memory Access (DMA)
controller. The only machine to use it is Philips CDi machine.
Machines that used it
Philips CDi.
68080/200MHz
A misunderstanding by many Amiga enthusiasts led to the belief
that Amiga International were attempting to persuade Motorola to
continue with their 68k series. This was due to comments by Petro
Tyschtschenko at the Cologne 1997 show that it would be easier to
develop a market if such a processor existed.
Machines that used it
None
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