Help designing a PIC16F877 Circuit, Btw, I'm new he

[fanir]

Heeelp.

 

[IanP]

In this JDM programmer the idea is to "steal" power from serial port, so you can't replace 1.5kΩ with a 15kΩ ..
Try any other resistor of,say 1kΩ to 2.2kΩ, if you have them, of course ..
Regards,
IanP

 

[fanir]

I've sorted that out, thanks alot mate. Anyway, sorry for the late reply.

Ian, I still don't understand on how to prevent ground loops? Sorry for being a pain. Is this correct?

**broken link removed**[/img]

 

[fanir]

Help? Ian?

 

[IanP]

You can open this loop by removing section starting from pin5 of DB9 and going diagonally to right-down, leaving pin5 connected only by the left track ..
Regards,
IanP

 

[fanir]

Ok, short all gnd.

Anyway, do you know where does pin 11 of LM324 go in the PCB layout above as it just shows a straight line?

Thanks for helping.

 

[IanP]

LM324's pin 11 is usually connected to 0V (GND) for single voltage operation, or to -V for +/- supply situation ..
Regards,
IanP