Re: 65816 & 8088's Memory

[et472@FreeNet.Carleton.CA (Michael Black)]

"Bryan Parkoff" (BParkoff@satx.rr.com) writes:
>     Okay, 6502/65c02/65816 have 256 byte size for stack, but x86 gives the
> flexible size for stack.  It can be 65536 byte size that we want to select.
> What about 680xx and PowerPC's stacks?  How many maximum size can stack
> support?
> 
I think the 6502 was an exception, with that limited stack space.  There
may be some obscure early CPUs that had limited stack space (if I remember,
the 8008 didn't even have a stack), but any of the big CPUs would have
a full range stack.  I think they'd also all allow for setting where
the stack starts, unlike the 6502 where it has to be in page 1.

I think this reflects the original intention for the 6502.  They
were looking  at what would now be called the embedded market, but
in truth all the early CPUs were created use in dedicated hardware
rather than a home computer.  So the page 0 addressing, save bytes
addressing memory, and put it low so it would be where memory
would sit.  A limited stack, and again in a specific location.
It's fine for when you had limited memory, but it got in the way
of some more complicated applications.

   Michael