In the latest kernel image, I2C speed is set to 1MHz - is that required for communication with the Navio+? Would a slower speed degrade performance? Does the Navio+ use the I2C bus?
Navio+ does use I2C bus - ADC, baro and PWM are connected to it.
We set it to 1MHz to have a good reserve of bandwidth, in fact 400KHz should be sufficient.
The sensor I was thinking of using only goes up to 100kHz, but i have an alternative that could go 2.5 MHz. What I2C addresses are used?
The addresses that are used by sensors on Navio are 40, 48, 50, 77.
Will I need to enable the device tree to make use of I2C, or can I just enable I2C? I’m using i2c-dev.h.
Default Raspbian requires some tuning. But in our distro everything is already enabled.