Help me with project about sending voice over a CAN bus

[micpic]

Does somebody have experience in sending voice over a can bus?
I have two can nodes in two Pic18f4580 controllers and want to send voice in phone qualitiy over the can bus.
How can I start? Are there existing projects?

regards

 

[bobcat1]

Re: Voice over Can

Hi


You must start by sampling the voice using the ADC in 8KHz smpling frequency

then compress the the voice data into lower size using some algorithm like ADPCM

dived the data into packet and send the packet using the CAN bus

When you receive the data decompress it and use an D/A converter to convert the data into voice again using 8KHz sampling rate


All the best


Bobi

 

[idlebrain]

Re: Voice over Can

I am not sure. CAN supports up to 1MBPS only. If it is sufficient it can be done.
Why not firewire.
Also not sure of the operating speed of the PIC cpu which is planned.



Cheers

 

[micpic]

Re: Voice over Can

The pic is currently running at 16 MHz but it is possible to run with 25 MHz.
The can baud rate is at 250 kBps.

Firewire can not be used.

 

[banh]

Voice over Can

what is the purpose of voice over CAN. CAN as i know can support maximum bit rate as 1Mbps, and usually not for multimedia application..

 

[micpic]

Re: Voice over Can

The purpose is to save money .
A can node is near the microphone. So it is suggestive to use this.