[NBLUG/talk] Bare metal question

[Steve Zimmerman]

On Sunday 25 May 2003 09:53 am, Mitch wrote:
> [snip]
>
> A register is a storage area.  It stores a small chunk of data in a
> space that is architecturally part of the processor, and that makes
> access to it very fast, since access doesn't need to be mediated by the
> address and data buses (which *help* mediate eletricity and  memory).
>
> It is not a memory location since it is not addressable in the standard
> way.   The are some specialized registers (program counter, stack
> pointer)  and then there are the general purpose registers (although in
> the x86 architecture, even the general purpose registers have weird
> restrictions.)
>
> The "not addressable" condition can be a little nebulous though.  Some
> RISC processors have large numbers of (truly) general purpose
> registers, and you can think about those as addressable, though they
> not addressed using the hardware address bus.   Also, you could also
> think about an L1 cache as a very large general purpose register.
>
> Ultimately what mediates eletricity and memory are the small
> capacity/transistor combinations that take a electrical state (high or
> low) and can repeat it at a later time.  Registers have nothing to do
> with it.

Thank you, Mitch.

	-- Steve Zimmerman