I bought EasyPic 5 developed board (secondhand). I install drivers for USB (Win10). Programator on board is linking and visible form Windows. When I try program some MCU (16F877A, 18F4550), programmer reported, there are PIC12F508 device. After force programing, red LED few seconds blinking, but programed device was without changing. The same situation, when i try Erase. Ater Erase an older program in MCu is still working.
I check signals on U2, U4 by osciloscope and it seems, there isn't problem here. Voltage on ZD1 is 5V and cca 12.5V while programing. All tranzistors are OK (Q6, Q7, UQ1). Jumpers "Socket selection" are on DIP40, MCU is on DIP40, everi piano switchers are OFF, jumper block "PGM PIN SELECTION" I try in avery posible configuration as J7.
Have somebody some idea or experience???
I solved my problem recently
I run programmer software and went to "Options"-->"Advanced options" and turn on "Disable VPP-First mode entry". After that action ti started work corectly. Then, out of curiosity, I turn off this option. And ...... programmer still worked corectly. I think, there is some bug here.