Problem with PIC18F4550

[mstalebi]

Dear colleagues,

I followed the instructions in the following website to create a USB interface with PIC18F4550



I used MCHPFSUSB framework to implement a HID device and I could send and receive data from PC.

Unfortunately, the board doesn't work with all PC USB ports. In fact most PCs fail to recognize the device properly and in most cases I've ended up with the "Device not recognized" message.

I would appreciate if you can help me resolve this issue.

Thanks.

 

[john blue]

Ohh... I am just starting to work on it...

 

[nandhu015]

Use USB Sniffer/Analyzer to monitor the communications going on between mc and pc.

You can find out the problem

 

[spiralbrain]

it is sometimes the USB capacitor grounded from pin 18, what value are you using ?

 

[mstalebi]

For that capacitor, I used 470 nf in accordance to CREATE design.

 

[Sink0]

I never worked with this specific project but i was able to create a very reliable USB connection using many PICs incluiding PIC18F2550. It is hard to find out what is going on just with a description. Can you take a picture on your board? Are using exactly the schematic provided on tis website? Take a look at VUSB voltage, how it is? Can you post the code and compiler you are using?