16bit pointer note

[pm]

I had difficulty using function pointers. Perhaps I should have been aware of this but I learned the hard way.
if preprocessor #device *=16 is in your source all variables that index or alter a pointer in any way must also be declared as long or int16. I was trying to index my function pointers with an 8 bit flag because there are only twenty functions. It worked great if the functions were in the same page as the calling func. when the flag is declared as a long variable it works. Even though the upper 8 bits are always zero's. Hope this can prevent some frustration for others.

[Guest]

Im, the #device *=16 instruction is only to be able to access more than 256 bytes in ram..

8bits pointers can point 0-255 byte in ram...
16bits can point 0-65535

[RKnapp]

Wait -- please explain. I'm a newbie using 18F8720 and know I'll need a lot more than 256 bytes of RAM -- I'm trying to compress a giant DOS app to fit into this chip.

So... should I be using #device *= 16?

Thanks for your help!