Some 8051 derivatives have a second dptr and a dps register to switch
between them. As far as I can tell, SDCC does not support that as of
version 2.3.0 (Apr 11 2002).
Is support for the second dptr available or planned?
I have noticed at least two implementations of the second dptr. One has
dpl and dph switch along with dptr when dps is incremented/toggled
(Philips). The other does not, and one must read/write dpl1 and dph1
(EZ-USB). So, not only would a switch to enable second dptr support
have to be there, one would also have to specify which scheme is being
Right now, I am managing this manually, including breaking into
assembly to save dps and dpl1 and dph1 in ISRs.