Re: How true...

[bieling@terra.es]

On Apr 21, 9:12 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:
>
> The original "TV Typewriter" was all TTL integrated circuits and
> shift registers--the 6502-based design was Lancaster's later RAM-
> based cost-reduction.
>
> The only "ultimately misguided" aspect that Cleaver refers to is the
> consumption of 85% of the 6502's time with video generation, leaving
> only 15% for computation.  For a "TV Typewriter" this seems like a
> very reasonable tradeoff--after all, it was intended to be a terminal
> for *another* computer, and using a 6502 saved a 6545 video controller.
>
> The Spectrum/Timex sub-$100 computers used a similar approach to video
> generation with a Z80, and though their speed while displaying was never
> great, it was adequate to interest many users.
>
> -michael

I can't find anywhere a 3rd version of the TV Typewriter cookbook,
unless it's "The Cheap Video CookBook", is it ?

--Jorge.