> Page 1 to page 2? Why? Page sizes are 2048 bytes each (11 bits), > and my ISR goes from byt 527 to byt 580, so I should not have to > worry about PCLATH. Or so I interpreted from the datasheet. > > Can you explain, por favor? > > BTW, no, I don't have any references to PCLATH in the ISR code, > for the reason above. In this case you were right. Bob screwed up, which is only noteworthy because it happens so rarely. ***************************************************************** Embed Inc, embedded system specialists in Littleton Massachusetts (978) 742-9014, http://www.embedinc.com -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics