16F877A ICSP

[Beefer3]

Hello all
I am trying to add ICSP to my project and I wired up the following schematic to my board.


I am using the 16F877A and the uJDM Programmer. My problem is that I cannot program or read my 877a with the ICSP circuit. I have checked and recheck my wiring and it is correct. Has anyone used these two circuits together with success?

Picture of the JDM Programmer included.

Actually, does anyone have any suggestions to a good circuit for ICSP?

Any help is appreciated.

Thanks

 

[Beefer3]

I forgot to mention that I am not using the 2 10 kOhm resistors. Pins RB7 and RB6 are used with an LCD. I have removed the LCD and tried to program/read with IC-Prog with no success. When I remove the PIC and go straight to my uJDM, it programs and reads fine.

Any help?

 

[Nigel Goodwin]

Once the PIC's oscillator is running you can't switch it to programming mode, to do ICSP you need some way of stopping it first - one way is to take MCLR low for a short time to reset the chip, then switch to programming mode before it can restart.

Your diagram shows you are trying to feed the entire target circuit from the programmer, depending on what else is connected, the JDM programmer may not be able to cope.