I finally took some time to change the raspberry pi to the revision B one. Java seems more confortable with 512Mb of Ram. The system now handle 16 different channels, but some still need work. I started a Seismometer, but I have to replace the ADC with a dedicated 16bits I2C one instead of using the integrated 12bit PIC ADC. I planned to add another probe with the house electrical consumption.
I hope to find time to document everything, anyway the chart web page is up to date :
Have a nice day !