I have the following hat http://wiki.seeedstudio.com/Raspberry_Pi_Relay_Board_v1.0 my image detects the i2c interfaces and mounts them in /dev as i2c-0  i2c-1  i2c-3  i2c-4, 

I can scan the different i2c interfaces as folloging interface

i2cdetect -y 1 

root@rockpi:~# i2cdetect -y 1
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: UU 11 -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --
 

I have set 0x20 address on my relay Board but cannot see the interface. 

 

Has anyone a hint what configuration settings i need to change

 

Many Thanks

 

Roman

1 minute ago, SecureXperts said:

root@rockpi:~# i2cdetect -y 1

So check on the other bus ...

root@rockpi:~# i2cdetect -y 2

2 minutes ago, pavelectric said:

So check on the other bus ...

root@rockpi:~# i2cdetect -y 2

Hi pavelectric

The /dev/i2c-2 is not available on my Image. Do in need to load some Kernel modules for that?

Thanks

31 minutes ago, SecureXperts said:

my image detects the i2c interfaces

The I2C present on Header pins 3 and 5 is the I2C7.

To get I2C7 appearing as /dev/i2c-7, it requires to load the rockchip-i2c7.dtbo overlay which is present in /boot/dtb/rockchip/overlay.

To do that, add the "overlays=i2c-7" into the /boot/armbianEnv.txt and reboot.

10 hours ago, martinayotte said:

The I2C present on Header pins 3 and 5 is the I2C7.

To get I2C7 appearing as /dev/i2c-7, it requires to load the rockchip-i2c7.dtbo overlay which is present in /boot/dtb/rockchip/overlay.

To do that, add the "overlays=i2c-7" into the /boot/armbianEnv.txt and reboot.

Hi martinayotte, 

thanks a lot for your input. Indeed i2c7 was not loaded. ;-) To add this overlay the good command is overlays=i2c7 without dash.

Now all my HATs communicating over this bus is working like a charm!