My xwisp (written in Python) will run on any platform that has a Python interpreter - most *nixes do. To change one word in a .hex file you could use xwisp.py target f877 load hexfile.hex patch 8:12 save hexfile.hex the target f877 is probably needed to switch to word-oriented adressing. for an 18f you'd use byte oriented addressing. just add something around this to supply the increasing numer. or jump into the python source and do it from within. Wouter van Ooijen -- ------------------------------------------- Van Ooijen Technische Informatica: www.voti.nl consultancy, development, PICmicro products docent Hogeschool van Utrecht: www.voti.nl/hvu -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist