Chip to PC problem

[Zcircuit]

I have a program on a PIC18F452 that needs to talk to the computer. The chip was sending garbage to the cmputer. I hooked a probe from my scope to see what was happening, and it started working. I could disconnect and reconnect the probe and the data would messup, and then start working again every time when the probe was connected. What's going on?

[mackrackit]

Sounds like the probe is acting as a capacitance filter. Try a cap from signal to ground.