That's correct.
for the HCS12X, __far data pointers can only point inside of a 64k page.
Or in other words, the pointer arithmetic is performed on 16 bits.
The reason of this limitation is not actually the pointer increment. Doing a 24 bit pointer increment is more expensive than a 16 bit one, but not that much. The main problem I see is that for offsets (e.g. ptr[1] or ptr->field), the compiler could never use any indexed addressing modes at all (with a offset != 0), as the CPU does not propagate the offset in its address calculations to the page. And that would really generate a lot more code when accessing struct fields.
Daniel
