Microsoft open sources GWBASIC

Fred Cisin cisin at
Sat May 23 22:25:15 CDT 2020

>> Later it offered the C128, which had multiple operating modes,
>> including a much better BASIC and an 80-column display, but also an
>> entire incompatible 2nd processor -- a Z80 so it could run CP/M. This
>> being the successor model to the early-'80s home  computer used by
>> millions of children to play video games. They really did not want,
>> need or care about _CP/M_ of all things.

On Sat, 23 May 2020, Jim Brain via cctalk wrote:
> Again, misleading.  The Z80 was not a design goal.  a 2MHz C64 compatible 
> with 80 columns was the design goal.  THank the Z80 on some Marketing shmuck 
> that promised CP/M compatibility on the unit (thinking the C64 CP/M cart 
> would work, which it can't, because the cart is badly designed, I am told it 
> was a bit f plagiarism from an Apple II CP/M card, but failed to take into 
> account the strange C64 bus cycle).  Bil is around and can happily tell you 
> the story of simply designing the Z80 cart into the main motherboard to 
> checkoff the requirement and quit having to fight to get the cart to work.

I met a few early purchasers of the C128.
They were C64 users who felt that they ALSO needed a CP/M machine, and it 
was handy to have both machines in one case.

It's possible that with a few more iterations, they might have been able 
to get the Z80 side and the C64 side to work together better.

Grumpy Ol' Fred     		cisin at

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