single base register for task relocation #9
Description
We want the very simplest support for relocatable tasks. Something on the lines of a single base register which offsets all addresses.
But changing this register would cause an immediate discontinuity in the program flow: we're almost bound to have some kind of supervisor mode or task identity. So this certainly needs more thought. Perhaps a mode bit is needed to suppress relocation which is set for interrupt handlers. We do at least have some spare bits in the status register.
Might need some discussion as to how or whether it offsets direct page and stack addresses.
Perhaps in the case of a unified (single-byte) address model we can just offset everything?
Garth seems to have in mind all the bank style registers of the 816 (D, PBR, DBR but full width)
http://forum.6502.org/viewtopic.php?p=17277#p17277