Such an approach has been taken to build an Atmel STK500 knockoff. http://www.tuxgraphics.org/electronics/200510/article05101.shtml I've got one of these, and the process went fairly well, albeit taking 45 minutes to load on & verify the initial firmware. YMMV. -Randy On 10/11/06, Bob Axtell wrote: > In the last two days, a potential client has requested something unusual. He > asked if there is a way to include the PIC programmer INSIDE the product > PCB. > > The idea is that he wants the PIC firmware to be update-able without any > external hardware (such as a PIC programmer). I guess that he wants the > PIC programmer to be "built-in" to the product, and accessible via a WinXP > system. His reason is that the use of external programmers is > error-prone for > the final client. > > Of course the bootloader came to mind, but PICs don't have an internal > bootloader, > so the "bootloader code" have to be programmed in anyway; so his > suggestion overrides > the input. > > So I have brainstormed the idea, and have one possibility as follows: > > use the FT232R with pins arranged in bit-bang mode. Control the 12V VPP > switch with the > pins, connect PGD and PGC to two other pins, and create a chargepump > with several .22uF > ceramic caps & diodes driven by the 6M osc bit-bang output. It would be > slow (relative to a standard > PIC programmer) but simple and tidy. To program the device, just connect > the FT232R to a host's > USB port and drive the application with a WinXP application. The WinXP > app needs to know only how > to program only ONE device. > > Flames appreciated. Other ideas welcome. > > --Bob > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > -- -Randy Glenn Computer Eng. and Mgt. Year V, McMaster University Regional Student Representative, IEEE Canada randy.glenn-at-gmail.com - glennrb-at-mcmaster.ca randy.glenn-at-computer.org - randy_glenn-at-ieee.org http://www.randyglenn.ca -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist