2 Oct
2007
2 Oct
'07
4:35 p.m.
Chuck Guzis wrote:
On 2 Oct 2007 at 15:33, Brent Hilpert wrote:
Oh, agreed too. I'm sticking up for the 990/9900 architecture, but in no way
trying to defend the 99/4 design. Based on what others are describing the
latter was amazingly limiting.
I guess home computing got tossed over to the consumer products division at
TI, which always seemed to have a bottom-of-the-line/low-end approach to
things, too bad they didn't find some middle ground between that and their
higher-end commercial/military stuff.
Though IIRC, with a well-designed stack
management policy, the register
frames could overlap, so as long as one didn't use the registers in
overlapping memory you were fine. You were not obligated to grab a fresh 16
words of memory on every function call. Equivalent in more conventional archs
to deciding how many machine registers you're going to save based on usage on
a function call rather than saving them all without question.
Agreed. But 128 words still doesn't leave much room for variables
beyond those that can be stored in the registers of each frame.
There's a comment on one of the 99/4A sites that 1,024 bytes of RAM
were originally planned, which is more reasonable. I doubt that TI
saved very much by using the 256 byte part.