I've built my own programmer (a serial programmer for both the EPROM
and Flash parts) and it programs great.  I'm having problems with the
"bulk" erasing of the program and data areas.  My first problem is
ambiguity in the data sheet.  In the data sheet it reads:

Bulk Erase Program Memory
To perform a bulk erase of the program memory, the following
sequence must be performed.
1. Do a "Load Data All 1's" command.
2. Do a "Bulk Erase User Memory" command.
3. Do a "Begin Programming" command.
4. Wait 10 ms to complete bulk erase.

But there are two "load data" commands, one for "load data for program
memory", (000010) and the other, "load data for data memory" (000011).
Ok, I assumed that if I was erasing  the program area, I'd use "load
data for program memory", and similarly for the data area.  Sounds
logical to me, but... it doesn't work.

It *does* seem to erase the memory location that I'm currently at,
in either the program or the data area, but I was under the impression
that a "bulk" erase would erase *all* of the respective memory locations
(data or program).

So, does the "bulk erase" erase one or all memory locations, and
if it does erase them all, how do you actually do it?  Have you
made the procedure in the data sheet actually work?

If you're the one who helps me solve this problem, I'll treat you
to your favorite coffee/tea/soda/beer the next time you are in
the Washington, D.C. area!

Matt


-----------------------------
Matt Bennett                |
mjb@hazmat.com              |
http://www.hazmat.com/~mjb/ |