From: Chuck Simmons
Organization: You jest.
X-Mailer: Mozilla 4.61 [en] (X11; U; Linux 2.0.33 i586)
Subject: Re: Flash errors with Atmel T89C51RD2
Date: Mon, 02 Sep 2002 12:50:55 GMT
NNTP-Posting-Date: Mon, 02 Sep 2002 05:50:55 PDT
Tilmann Reh wrote:
> we have just designed the Atmel (formerly Temic) T89C51RD2 into
> a new project where we need some of its specific features.
> We programmed the device using the built-in ISP bootlader and
> the Atmel FLIP software.
> All units performed well immediately after programming, and did
> so for some time. However, later some units didn't restart the
> application software after cycling power down. Reading out the
> contents of the flash program memory showed that some areas
> were (completely or partially) erased, i.e. filled with FFh.
> The application code does not make any use of flash programming,
> neither was anything connected to the serial interface (so ISP
> erasure can't be the reason).
> Did anyone here also notice something like this? Seems like the
> chip (partially) forgets its contents. The affected address area
> seems to be individually different, but reproducible (i.e. one
> individual chip always forgets the same area).
I've seen this with flash FPLD's. In this case, a Kanda low cost
programmer was being used and programming multiple times with the same
data cured the problem. A later switch to a Needham's programmer
eliminated the need for programming several times. If the FLIP software
allows it, try multiple programming of the part.
... The times have been,
That, when the brains were out,
the man would die. ... Macbeth
Chuck Simmons email@example.com