I have bought the enhanced version from e-bay and I could write and verify on AT89S52 but I couldn't program 16F84A or 16F876A. Checking the voltage in HW test setup I found the following voltage in address pins. (VPP is 12.10v)
Address 11, 9, 17 and 15 is obviously low. According to willem.org site Address 9 has reason to be low. But I have no idea how to fix the other voltages. There is no schematic and there is no part number on the board. Can anyone please help me on figuring out what can be the possible reason for the problem and how to fix it?