On Don, 26 Apr 2001, you wrote:
>I'm using E2PROMs with my 8051 (on the NewMicros NMIY0031 card) with almost complete success. My only failing is that I'm trying to use the Software Protection Mechanism to "Write Protect" the memory chip. This is where you quickly write strange values to strange addresses on the E2PROM. But it doesn't work.
>Questions: Is it possible to do this from a 8051 based system or do I need a EPROM blower to do it? Could it be that the NMIY0031 card is "waiting" between memory writes so that the writes are not being done quickly enough?
If you can write to this card then you shold also be able to lock the card.
Lock in your rst or asm file for additional accesses or "away optimized "
instructions to the Memory.
I have only the docu for the at29c256
The docu says OE must be High while sending the sequence :
You can also write the sequence in inline-assembler.