Hey all

 

I'm trying to get an Orange Pi Zero (256MB) to talk with an MPU6050.

(ARMBIAN 5.31 stable Ubuntu 16.04.2 LTS 3.4.113-sun8i)

 

I've installed i2c. 

 

When I have a little OLED screen attached I get:

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

 

This is good, the OLED is at address 0x3c, and there's something built in at 0x48 which is alreaedy being used.

 

But when I plug in my MPU6050 i get:

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

 

I.e. it is undetected

 

So i tested with the following all connected on the same I2C bus:

 

* Orange PI Zero

* Arduino Uno

* MPU6050

* OLED 128x64

 

The arduino will happily work with the MPU6050, whilst the opi will see the oled on the 0x3c address. All electrical connections are triple-checked (OLED is connected after the MPU6050 in the circuit).

 

This suggests that the OPi is unable to communicate with the MPU6050 for some unknown reason. Does anybody have any hints as to what could be going wrong?

 

I know that the MPU6050 should be seen on 0x68 (AD0 is low). Maybe addresses above 0x63 have an issue?

 

 

 

 

The UU at 0x48 looks strange, because I don't have that on my OPiZero with Mainline.

UU means that it is in use by a kernel driver ...

 

will test with mainline now...

mainline currently doesn't boot on my opi0

Armbian_5.27.170614_Orangepizero_Ubuntu_xenial_dev_4.11.3

 

2 red flashes after boot, and doesn't respond to ssh

 

switching in old sd card works fine (legacy)

 

is there an older mainline build which works well?

Do you have any USB Serial to connect and capture log during your Mainline boot ?

 

no. But i definitely should get one.

 

it seems to be perhaps an SD card issue. Which is a shame because it's brand new and i just ordered 200 of the same. From the same batch the first one works fine, the second one doesn't. 

SanDisk 8GB MicroSD HC1 (genuine)

 

Investigating...

The UU at 0x48 is used by pcf8591 kernel driver.
Please add pcf8591 to /etc/modprobe.d/fbdev-blacklist.conf and reboot.
 

Before edit

$ sudo i2cdetect -y 0
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- UU -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --

 

After edit

$ sudo i2cdetect -y 0
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --

 

Why it is required to add that in blacklist if there is no PCF8591 present on OPi0 ?

And if it is actually present on I2C bus, it should appear as 48 instead of UU after blacklisting it.

 

 

3 minutes ago, martinayotte said:

Why it is required to add that in blacklist if there is no PCF8591 present on OPi0 ?

Side effect of adding patches to support the "Matrix" kit from FriendlyArm. New modules don't read script.bin values and are loaded always.

@zador.blood.stained, I don't understand your reply. We are talking about OPi0 here, right ?

My OPi0s with Mainline don't load any PCF8591 driver, and i2cdetect doesn't show this 0x48 ...

 

27 minutes ago, martinayotte said:

@zador.blood.stained, I don't understand your reply. We are talking about OPi0 here, right ?

We are talking about the legacy kernel

 

On 30.07.2017 at 1:43 PM, Elliot Woods said:

(ARMBIAN 5.31 stable Ubuntu 16.04.2 LTS 3.4.113-sun8i)

 

obviously mainline won't try to load anything that is not listed explicitly either in /etc/modules or DT