I wired a board (without the programming circuits) to try to do romzap and zaplab, but no headway with the board talking to PC romzap or zaplab program so far. The mpasm ver 2.15 is downloaded from http://www.microchip.com/10/tools/archive/other/index.htm and unzipped to c:\program files\mplab\ Then I tried to let romzap created a bootloader hex file without changing default any parameters, but the assembler assembled with 243 errors and 222 warnings. The romzap version is v290800. Any hints? I will try to read the romzap help file again now. Ling SM -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu