>>2)  What is this whole shebang about two banks of registers?  If I need to
>>swap the two banks in and out, why do they have different addresses?  I'm
>>confused.  I mean, portc is at 07h and trisc is at 87h.  They have unique
>>addresses, why is it necessary to switch banks?  Can't they just be
>>addressed directly?
>>
>
>Well they can be addressed using thier full address INDIRECTLY.  The PIC
>instruction format does not allow space for the full 8 bit (or longer)
>address of the RAM location.  There are bits in the STATUS register that
>"complete" the address.  I think all of the current PIC's only have two
>banks and only use RP0 but the architecture allows for RP1 to address two
>more banks.
>
>See the databook for more details.


NOW it makes a whole lot more sense.  The databook didn't explain it as
clearly as you just did.  Thanks!

-Matt


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