[sdiy] Re: Bottom Ten ICs

[Theo]

You mean TMS9900, a brilliant processor IMO.
The whole address space works as register space, no stack pointers and stuff
just use a other memory area for your registers instead.
Really a treat to code for :)
It was also fast,  about the same performance as a 68000 @ 4Mhz.
Keep in mind it dates from the late '70s.
Z80 or 6502 where considered state of the art but those delivered far less
performance than the TMS9900.


Cheers,
Theo



----- Original Message -----
From: Rainer Buchty <rainer at buchty.net>
To: Richard Wentk <richard at skydancer.com>
Cc: <synth-diy at dropmix.xs4all.nl>
Sent: Thursday, October 07, 2004 2:10 PM
Subject: Re: [sdiy] Re: Bottom Ten ICs


> >That TI processor from the late 70s which kept could only ever keep
> >internal registers in external memory. Duh.
>
> Back then it was no stupid idea cause memory was fast enough. So why
> waste internal resources? From a today's perspective it may seem stupid,
> but back then it was not unreasonable.
>
> Mind you, those where the times when two processors (like 6809 or 6502)
> could share the very same RAM without interfering.
>
> Rainer
>
>