Invisible wrote:
> Note also that the 6502 doesn't have any microcode. 

Given how the instruction sets decoded, I'm not sure it's really valid to 
say it had no microcode. There were definitely cycles of stepping thru the 
code and branching around in the PLA data.  I'm not an expert, but it wasn't 
really hard-wired logic as such. The HCF instruction, for example, was an 
emergent property of the "microcode" interpretation and not something 
necessarily intentional.

-- 
Darren New, San Diego CA, USA (PST)
    Eiffel - The language that lets you specify exactly
    that the code does what you think it does, even if
    it doesn't do what you wanted.

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