On Mon, 29 Jun 1998, Caisson wrote:

> > Van: Rob <robzs@HICOM.NET>
> > Aan: PICLIST@MITVMA.MIT.EDU
> > Onderwerp: Reading a programmed PIC
> > Datum: vrijdag 26 juni 1998 19:38
> >
> > Hello again fellow PIClisters,
> >
> > Can someone tell me if it's possible to read a PIC that has had it's
> > protection fuse blown?  I've heard there's a way to apply a voltage and
> > put it into test mode.  If I create a programmed chip and protect it, can
> > someone else come along and copy it?  Are there any ways to prevent this
> > from happening?
> >
> > Thanks
> >
> > Rob
>
> We (here on the list) do not know how to do it.  But alas, with enough
> intention (read : mony and time) all protections are defeated.  The
> Code-protect works (as far as I know) like a charm.  But if you want extra
> protection you can try to disable the programming-communications data-pin
> (PB7).  This is done by distroing the output-stage of that pin, resulting
> in a input-only line.  There was a thread about that some time ago (see the
> archives.).

Thanks, I shall check.  Although the archives are pretty big to sift
through.  Too bad there wasn't a better search scheme.

Rob


>
> Greetz,
>   Rudy Wieser
>