Your mini-schematic shows all the lines going through a '14 inverter. But based on the pins you are using I'm guessing that you're not really passing it through the inverter but through your '126.

Assuming you're using the '126 then it appears to me you have pins 5 and 6 on the '126 backwards. The input (pin 5) should be MISO on the AT89S8252 and the output (pin 6) should go to pin 10 on your parallel port (with the resistors).



Do you have any way to load a program on your Atmel without this programmer? Or a scope to see if you're getting some action on the ALE line when EA is tied low?



Funny you should ask. I lost a lot of time on this circuit myself because my crystal wasn't connected to X1 and X2. That also seemed to cause a voltage drop from 5V down to about 3.9V when external logic circuits were attached to the microcontroller. So swapping out your crystal or at least double-checking the connections is probably a good idea.

Regards,
Craig Steiner