CAN sniffer using the at90can128 uc. Help needed

[pict]

CAN sniffer

Hello everyone!
I am presently doing a project related to the CAN protocol.I am using the at90can128 uc.The compiler used by me is gcc compiler in avr studio 4 environment.
My job is to convert the incoming CAN frames into a PC compatible format(preferably USB) and transfer this message to the PC.An ui application on the PC will accept this incoming data and accordingly display the ASCII value of the incoming message.

Can any of you please guide me on this project.If any of you have some sample codes can you please share it with me.
Please help me guys!looking forward to your replies

ps:I am attaching the schematic prepared by me.Please go through it and let me know any defects/improvements

thanks
vijay

 

[svhb]

Re: CAN sniffer

You probably need to configure the CAN controller into the "Listen only" mode.

I don't looked into your files or specifics for your microcontroller, but you need to prevent that your analyzer tool is really joining the bus. The listen only mode basically suppresses the generation of acknowledge bits from the sniffer tool so the communications stays exactly the same if the tool is connected or not.