I2C support is in code from git now:https://github.com/8devices/carambola2/ ... dd7a1b6d35
There it says:
i2c pins: sda - GPIO18, scl - GPIO19
I used recent code, and my Carambola2 says while booting (got it with "dmesg | grep i2c"):
[ 0.550000] i2c-gpio i2c-gpio.0: using pins 18 (SDA) and 19 (SCL)
I connected a RTC that works fine using annother board to Pins 18 and 19 of the Carambola 2 module using 10k pullup resistors to 3.3 V. Unfortunately, this does not work.
The problem is: "using pins 18 (SDA) and 19 (SCL)" means in fact GPIO 18 and 19.
To get this clear: When using the Carambola2 eval board, connections are like this:
SDA is GPIO 18 -> Pin 6 of Carambola2 module -> Pin 10 of J12 of eval board
SCL is GPIO 19 -> Pin 5 of Carambola2 module -> Pin 11 of J12 of eval board
Hope that helps avoinding the trouble I had when i mixed up pins and gpios.