Pic16f870

[canadaelk]

I service a product using this uP. The OEM is out of business and I have no help there.
Is there a way (or someone who can help me) getting the code into some new OPTs (pereferrabl without having to remove a good one from a working board) so I have spares to service my customers
Thanks, E

 

[duffy]

First off, that chip has a code-protection option. If it is set, you are SOL.

Assuming it isn't, is the chip through-hole, PLCC, or surface mount? If through-hole or PLCC in a socket, you are in luck - remove the chip, plug it into a Picstart and read the code. If you don't see a bunch of FF's on the screen around address 0, you probably have the code and can start programming replacement chips.

If the chip is an SMT soldered to the board, first study the traces and see if the PGM, PGD, and PGC pins (use this - https://www.electro-tech-online.com/custompdfs/2011/11/30569b.pdf ) go to a separate connector. If so, that will be an ICP (In-Circuit Programming) connector, and you can wire up a cable to the Picstart, power up the board, and read it that way.

If not, things get more complicated, they were probably factory programmed. You are going to have to remove the chip and make an adapter board for the programmer, and the odds of it having code protection go waaaaay up.

 

[canadaelk]

duffy:
Thanks for your quick reply. The 16f870 is a 28-pin SOIC and the 3 pins are brought to a connector (shared with an entry keyboard during use).
I do not own a Picstart Plus programmer (and do not want to spend $200+ on a goose-chase). If you own one and are willing to look at this, send me a PM and we can work out the rest.
Cheers, Elk

 

[duffy]

I will charge you more than the modest cost of that programmer.

 

[BeeBop]

What part of the country are you in Elk?
I've been able to read the hex on a surface mount PIC in a product, which I service, with a PICKit 2. I was surprised it wasn't code protected.

 

[canadaelk]

BeeBop: New Westminster

 

[BeeBop]

Well we could see if the PICKit will read your chip. I sent you a PM...