I am having a problem with the Atmel parallel port programmer, which design is on their website. I can read a chip and partially program one however I cannot seem to be able to program memory locations 0-3.
I have tried 3 chips, two 89C51 and one 89C2051, none of which will program locations 0 - 3. I have checked all the wiring but I cannot seem to solve the problem. Does anyone have experience with this circuit and software? or even a possible fix.

Steve Troup