I am trying to read a 27C256B. When I read the chip in everything says its working just fine. The software verifies the chip type and loads all of the information into a buffer and then opens up the data in a hex editor. The problem is all of the data comes up as 00. Is there a problem with my EPROM or is this because there is some kind of encryption on the chip?
I don't want to erase it because it has information on it that I am trying to read. However, every time I read it I get all 00 which is odd and I am wondering if you can lock an EPROM.