I2C on ubuntu linux 3.8, BBB pin confusion?

Hi All

I’m new to i2c on BBB and have some questions.

I just recived my i2c pressure censur with address 0x60.

I use beaglebone black and ubuntu 13.10.
When I boot I have /dev/i2c-0 and /dev/i2c-1.

I can use: echo BB-I2C1A1> /sys/devices/bone_capemgr.9/slots
and get /dev/i2c-2

when do: cat /sys/kernel/debug/pinctrl/44e10800.pinmux/pingroups
I get:

group: pinmux_i2c0_pins
pin 98 (44e10988)
pin 99 (44e1098c)

group: pinmux_i2c2_pins
pin 94 (44e10978)
pin 95 (44e1097c)

group: pinmux_bb_i2c1a1_pins

pin 96 (44e10980)
pin 97 (44e10984)

But how do I translate this to pin numbers on P8 and P9?

Best Regards

Take a look at this thread/post, it should help:


I’m not sure if either my sensor isn’t working or if it is something else.

I’ve tried all combinations of 17,18 / 19,20 / 21,22 / 24,26

Ok, I did a cycle of the reset pin on the sensor board, and now it responds to i2cdetect -r 1 at address 0x60 :slight_smile:

this is using pins 19 for CLK and 20 for DATA.
with VDD at pin 5 (5V)

thanks for the link.