68K Macs with MacOS 7.5 still in production use...

Chuck Guzis cclist at sydex.com
Thu Sep 15 13:24:11 CDT 2016

On 09/15/2016 11:03 AM, Peter Corlett wrote:
> On Mon, Sep 12, 2016 at 01:40:56PM -0700, Chris Hanson wrote:

>> No, the 68000 was a 32-bit CPU, as defined by the register width
>> and programming model. The fact that it was implemented with a
>> 16-bit ALU and had a 16-bit data path to memory is immaterial.
> By that logic, the Z80 is a 16 bit processor because ADC HL, BC and
> the like exist. It even has a 4 bit ALU and passes data through
> twice, but this is an invisible implementation detail and it's
> generally considered to be an 8 bit CPU. Likewise, the existence of
> zmm0-zmm31 registers don't mean that contemporary x86 is 512 bit.

My 68K manual, as handed to me by the Moto sales guy at Wescon back in
the day says "MC68000 16-BIT MICROPROCESSOR User's Manual".   Page 1-1
reiterates essentially the same sentiment:

"The MC68000...combines state-of-the-art technology and advanced circuit
design techniques with computer sciences to achieve an architecturally
advanced 16-bit microprocessor."

Call it anything you want, but we know what Motorola called it.


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