On Wed, Oct 13, 1999 at 01:39:23PM +1000, Jim Robertson wrote:
> More important to note is that if the LVP pin is raised simultaneously with
> VDD, the flash parts lock-up and you cannot enter the program mode. There
> must
> be a delay before raising LVP. This can be done with a simple RC network
> as done on the PROPIC II programmer.
>
> If you are powering the DUT from the target board then I would think that
> connecting the programmer's switched VDD to the LVP would work and solve both
> problems together.

What does it mean that "flash parts lock-up"? Is it possible that code EEPROM wo
rks
but data EEPROM doesn't? I've observed such a strange behaviour in my programmer
(http://www.ise.pw.edu.pl/~wzab/picprog/picprog.html).
I have modified the PICPRG2.2 software for 16F877, and code was programmed perfe
ctly,
but the data EEPROM was always read as "0" (I reported it to the piclist a few
weeks ago).

--
                        Wojciech Zabolotny
                        http://www.ise.pw.edu.pl/~wzab

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