> What I want to do exactly is to have to variables, one with the port I > want to use (let4s call it "port") and another one with the bit I want to > read (let4s call it "bit") then use the instruccion btfss. > > Something like this: > > porta --> port > 3 --> bit > > btfss port, bit > > What should mean btfss porta, 3 > > Is it possible? If "bit" and "port" are assembler variables, then yes. No matter how you may try to disguise it, the register and bit referenced by a BTFSS instruction are hard coded into the instruction, and therefore must be known at assembly time. If you need to dynamically select a register at runtime, use an FSR. There are more options for dynamically selecting a bit, most of which require bit shifting or mask selecting. ***************************************************************** Olin Lathrop, embedded systems consultant in Devens Massachusetts (978) 772-3129, olin@embedinc.com, http://www.embedinc.com -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.