N900 FM transmitter and receiver
 

Hi,

I was wondering if it is possible to build an application that enables short-range data communication between two N900 phones, using the FM transmitter and receiver. While the FM radio only transmits and receives analog (audio, 0-15KHz) signals, what we need to do is to encapsulate data in the audio signal at the transmitter and do the reverse thing at the receiver. This is a little like coding and decoding in communication.

Now the problem is, how can I actually save the (digital) audio received by the FM receiver in N900? I checked the FM receiver chip BCM2048 and it seems that it outputs a digital audio signal to the I2C bus. I guess there is a ADC implemented in the chip.

Does anyone know how to capture this audio signal? The two interfaces to the driver, V4L and sysfs seem not adequate. I appreciate your help since I'm pretty new with Maemo.

Thanks a lot:p