Thursday, May 2, 2013

Bringing up a new cape for the Beaglebone Black, i2c-1 is actually I2C2

Dual Motor Controller Cape on top of Beaglebone Black!
I am currently trying to bring up the Dual Motor Controller Cape on the brand new Beaglebone Black, and finding out the gotchas along the way.

First off, when I attempted to find all the i2c interfaces using i2cdetect, I got the following screen:

Where is I2C2 ??  The Beaglebone is supposed to have 3 I2C interfaces, and I2C2 is supposed to be the one connected to the EEPROM of the capes.

Fortunately, with help from panto on the IRC channel (freenode/#beagle), I found out that i2c-1 is actually I2C2.   Executing the command 'i2cdetect -r 1' and monitoring on the scope actually proves that i2c-1 is actually I2C2!


1 comment:

  1. But then if I2C2 is /dev/i2c-1, where will I2C1 be?
    Why would the developers have done this?
    (I remember that on the White BB the third bus i.e. I2C2, was a 1.8V bus, but it doesn't seem to be the same for the Black BB, hopefully)

    Btw, this is the type of post that the BeagleBone community needs but unfortunately there aren't many!