Hello,
does anyone know the meaning of System keyword ?
It highlights in the editor, but I haven't seen any information about this word (may be I'm blind tonight ).
Regards,
Herve
System Keyword
Moderators: David Barker, Jerry Messina
It's used to declare aliases to special file/function registers. You can find it in the modules containing the definitions of PICs (include module for each microcontroller).
As for its meaning, I dont realy know about it as it's not documented. But I think that it's mainly a hint to the compiler to treat the variables of type system differently than other vars:
for example if an instruction like x = x + 1 is translated for NRORMAL vars to " INC f " the compiler will not do that for a Portx variable (alias) because of the RMW behaviour..
I think this keyword mainly gives to the system SFRs aliases some of the properties of VOLATILE like vars (in "C" language).
But sincerly I'm not aware of the real meaning, all that is a simple guess (as I dont see how the compiler can do to make the diff between (hard related and maped) SFRs and normal vars.
Regards
As for its meaning, I dont realy know about it as it's not documented. But I think that it's mainly a hint to the compiler to treat the variables of type system differently than other vars:
for example if an instruction like x = x + 1 is translated for NRORMAL vars to " INC f " the compiler will not do that for a Portx variable (alias) because of the RMW behaviour..
I think this keyword mainly gives to the system SFRs aliases some of the properties of VOLATILE like vars (in "C" language).
But sincerly I'm not aware of the real meaning, all that is a simple guess (as I dont see how the compiler can do to make the diff between (hard related and maped) SFRs and normal vars.
Regards