TI 990 architecture / was Re: TI-99/4A Floppies

[woodelf]

Peter C. Wallace wrote:

> The registers-in-memory architecture might be suitable for a FPGA CPU 
> where BlockRAM (as system memory) is almost as fast as registers. Why 
> not have registers in memory instead of simulatiing it badly (and 
> expensively power wise) via caching, that is, why move data if you dont 
> have to?

Simple registers are expensive. Look at the PDP-5. This is the 1960's
when most architectures where developed. Even the PDP-10 I think
was designed to use core memory as registers unless you want the
optional module for F/F registers.
Ben.