PIC18F6680 programming

[atwoz]

Use Google and do a little research about ICSP, that might help.

[gopher]

I hope you don't get the idea that i came here without trying to research this stuff.

Look here
http://s261.photobucket.com/albums/i...rrent=BACK.jpg
and here
http://s261.photobucket.com/albums/i...rent=front.jpg

If someone could tell me what pins on the PIC the 3 data lines connect to??? Is that asking 2 much?

[rhino]

The new devices we reprogram with a laptop that has special software that sends data via the serial port straight into the max232e thats wired directly to the PIC. The older devices are exactly the same except no connection port and no mac232e chip. from what i can see there are only 3 connections from the max232 the the PIC

The problem here is without knowing the hardware or software differences between the two versions, who's to say the second version (with the max232) was loaded with a bootloader to allow for field updates? The first version could have been programed using ICSP or could have just been programmed and soldered into the circuit without regard for future updates.... hence the second version that is field updateable.

[gopher]

OK good point. Thanks for the reply. that is a very real possibility. Since the PIC chips are exactly the same I think it may be worth a try to save some money.

[rhino]

I understand where you're coming from. But you got to look at it this way... without knowing all of the details of the revision, you may end up with a smoked board, and end up paying for a new one instead of an upgrade.... or whatever the details may be in your case. Hate to see that happen.

[gopher]

the thing is we got tons of extra old ones that will probably hit the trash if we decide to buy new

[rhino]

Well... if you've got tons of old ones, hack away. That's my favorite way to learn about something. Personally, I'd desolder one of the old ones and see if the code protection fuses were blown, then inspect the circuit boards to see where the differences were. If the only differences is the serial connection, then chances are the manufacturer found a bug, fixed it, then thought to themselves.... hmmm what if this happens again? So they decide to flash it with a bootloader so they can send Joe customer a new revision that he can update himself instead of sending in a board, or buying a new one, etc. Sounds like you've got nothing to lose but time and sanity! Have fun with it.