Vusb capacitor for USB comms with 18f2550

[rjones2102]

Thanks again Steve,

The only reference to capacitance on the tiny datasheet for the crystal says:

Load Capacitance: 32pf
Shunt Capacitance: 7pf maximum

What does that mean!

Like I said on some other thread I started, the amount I am learning on this project, I will be able to answer questions myself soon! It's amazing how much you can learn at 18 hours a day!

Cheers

Rich

[mister_e]

I would suggest you try a SerialCommunication test, let's say @19200 bauds, then 115200 baud. If this work, then look at the USB code.

Refer to table 2-2, they recommend 15 pF. But yeah... depending the precision of your capacitor 22pF might be too high. If you have any scope handy, use a 10X probe and looks at OSC2 pin.

4MHz work also just fine.