Topics

  Hi all,
  I am Nova, I have done very much with P89V51, and I meet a problem with P89V51RB now.
I have two kind of P89V51RB, one 's label is white and one 's is yellow white. The White is very good, but the Yellow have some problem:
- First, one year before, We could not erase chip normaly but we must used Erase Flash Page to erase chip.
- Second, with the White, I can protect my program easily by choosing: Program Security Bit with Serial Number Setting. But with the Yellow label, I can not do that. Because after I do that, I still choose Display Memory and read the program easily.

  I have 2 kind of P89V51RB2FN, one 's label is white, and the other 's label is yellow. With white label kind, I have no problem. But with yellow label kind, I have a big problem: I can not erase Flash Rom. I can use Flash Magic to download program at the first time and it work properly (because at the first time, all Flash are 0xFF). After that, If I chose erase Flash from ISP menu, the Flash still keep the old value.
  I don't know how is different between two kind of chip have. The white label I had 6 month ago, and the yellow label I have just received them.