Please correct me if I'm wrong (I'm thinking aloud here) but this is the way I understand the memory organization of the 18F series: the access bank, which includes the first 128 bytes of GPR memory and the upper 128 bytes of bank15 (18F1320) for the SFR's. There is need to do any bank switching to get to anything in the access bank. Set BSR to 1,2,3, etc. to work with the GPR's in those banks (in addition to the 128 GPR's in the access bank), so at any given time once BSR has been set 384 bytes of memory are available. So if I set BSR to 1 then I have 384 GPR bytes available. Am I correct? Another question. I've been using the RES directive for declaring my variables. My question is, how can I declare something like the following variables and force them to reside in a specific bank, lets say bank 5: var1 res 128 var2 res 128 Regards, Bob _______________________________________________ http://www.piclist.com View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist