hi! i'm working happily on making a 16C505 programmer out of an old 16F84 programmer. i quote from ftp://ftp.microchip.com/Download/lit/suppdoc/specs/30603b.pdf (thanks Wayne!) page 2 "Incrementing the PC once (using the increment address command) selects location 0x000 of the regular program memory." this seems odd and different, but it sorta makes sense, as i see the same mentioned for the 12C509 (that's next :-) but not the 16C622 (that's next next :-) so i wonder is it set that way so it comes up pointing to the MOVLW XX pre-programmed OSSCAL load instruction, and that the one increment wraps us around to 0x0, the beginning of program memory? -- rob -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.