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The 680x0 Processor ---- |
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Powered by a 32-bit internal processor, the 68000 could address up to 16MB of RAM and run at over three quaters of a MIPS (Million Instructions Per Second) on an 8MHz machine. The 68000, or 68K, externally ran a 16-bit interface. The Amiga 1000, 2000 and 500 that used the 68000 processor were clocked at 7.14MHz.
Machines that used it:
A500 | A500+ | A600 | 1000 | 1500 | 2000 | CDTV
Used in the Sinclair QL, this cheaper version of the 68000 chip, has a 16-bit CPU, but only an 8-bit data bus.
Machines that used it:
The 6810 was a a special version of the 68K chip which was 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. Modifications meant the 68010 was slightly faster than the 68000.
Machines that used it:
Available as an upgrade for A500 owners.
The 68012 chips was never used on the Amiga.
Can you believe Motorola originally intended this chip to be used in video and washing machines!! A full 32-bit version of the 68000 chip. The 68020 chip brought the amount of useable memory up to 4 gigabytes. The EC (Embedded Controller) version found in the A1200 is only able to use a maximum of 16MB of RAM. The chip also heralded the introduction of an instruction cache in order to increase the speed of operations. Unfortunately the EC version found in the A1200 does not contain cache memory because it was cheaper.
Machines that used it:
A1200 | Some A500, A500+ and A600 accelerators
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
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
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
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:
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