I have a simple JNI app to interface the I2C ports. The problem I am seeing is that if I use /dev/i2c-3, the data and clock are active on the I2C-4 port (J13 pins 35 & 37) instead of the I2C-3 port (J13 pins 31 & 33). If I change the program to use /dev/i2c-4 instead it fails on the open(), presumably because there is no /dev/i2c-4, only -0, -1, -2, & -3. How are the I2C ports really mapped on the expansion connector?
