On a RPi 3, default SDA-I2C and SCL-I2C are assigned to pins 3 and 5 (same as GPIO02 and GPIO03).
Is possible to change to another pins? How can I do this?
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You can implement a software I2C bus on any pair of spare GPIO. You will need to add resistor pull-ups to 3V3 on any spare GPIO you use. For reference pins 3 and 5 have 1k8 pull-ups to 3V3.
You create the software bus by adding a configuration entry in
/boot/config.txt. For details see
Name: i2c-gpio Info: Adds support for software i2c controller on gpio pins Load: dtoverlay=i2c-gpio,<param>=<val> Params: i2c_gpio_sda GPIO used for I2C data (default "23") i2c_gpio_scl GPIO used for I2C clock (default "24") i2c_gpio_delay_us Clock delay in microseconds (default "2" = ~100kHz) bus Set to a unique, non-zero value if wanting multiple i2c-gpio busses. If set, will be used as the preferred bus number (/dev/i2c-<n>). If not set, the default value is 0, but the bus number will be dynamically assigned - probably 3.
E.g. to create a software bus on (Broadcom numbered) GPIO 5 and 6 add the following line to
/boot/config.txt. You will need to reboot for the change to take effect.
A new bus
/dev/i2c-3 will be created. You may use all the standard I2C calls to use the bus.