[Coco] [OFF] Hitachi MB-6890 information needed

[Darren A]

On Tue, Apr 22, 2014 at 11:55 AM, Gene Heskett <gheskett at wdtv.com> wrote:

>
> Correction, the contract with moto was to make a workalike clone in cmos,
> but hitachi never saw a moto chip mask.  They were much more advanced in
> cmos than moto was, made the workalike, but had so much empty space in the
> microcode table that their folks had lots of fun adding stuff.  But their
> clone contract with moto precluded it being promoted as better, only a
> clone in cmos.  And that it why to this day, hitachi will not even give a
> reply comment to any questions about its improved abilities.


Apparently Motorola didn't have a problem with Hitachi adding extra
instructions to the 6801/03.  The CMOS equivalent HD6301/03 has a few of
the secret 6309 instructions as well (AIM, OIM, EIM, TIM). But these are
documented in the data sheet for the HD6303. Maybe they just went too far
with the 6309 additions.

Darren