Am Friday 08 February 2013 17:10:00 schrieb Pascal Gosselin: > I have found a good reference on how to best handle I2C cabling. It's a > PowerPoint Presentation from Texas Instruments, I made a screenshot of > the relevant image: > > http://s7.postimage.org/t9bfk47hn/Screen_Shot_2013_02_08_at_11_00_03_AM.png > > As I suspected, only one end of the shield gets grounded, individual > coaxes for SCL and SDA. > > Google I2C cable issues.ppt to find the original document as the > first hit. > > Now I have to source some extremely tiny minature coax, ideally with a > solid core (for easier soldering to the pads on the NavBoard and the > GTA02). Looking for recommendations, ideally something I can order from > Digi-Key, Newark or Mouser in smaller quantities (it's not like a need a > 1,000 foot roll!). > > It's not clear IF the power supply wires should be shielded. I think I > will try to see if it makes a difference for the GPS. > > -Pascal
You should use fine pitch flat ribbon connector or flat plastic connector like on LCM, and shield it with a metal braid sticky tape, again like originally done in GTA02 LCM connection. For further crosstalk and EMI shielding run a GND wire as every 1., 3. aso wire in your ribbon cable. Ulrathin coax is *extremely* expensive and hard to source /j _______________________________________________ Openmoko community mailing list [email protected] http://lists.openmoko.org/mailman/listinfo/community
