Can I run example code to test Navio2 sensors before quad build?

Navio / Edge Hardware
1

I’m working with my teenage son to build a quad using a Navio2. We wanted to try the example code for some of the sensors before completing our build. Some of the examples seem like they should run with just the Navio2 and a Raspberry Pi 2 (no other hardware attached).

However, we are having mixed results with the different example code (tried both C++ and Python):

Can anyone verify that we should be able to run these examples without any other hardware attached?

  • Barometer
    C++ - runs successfully
    Python - will not run…
pi@navio:~Navio2/Python $ sudo python Barometer.py

Traceback (most recent call last):
File "Barometer.py", line 13, in <module>
	import navio.ms5611
File "/home/pi/Navio2/Python/navio/ms5611.py", line 31, in <module>
	from smbus import SMBus
ImportError: No module named smbus

  • RGBLed
    C++ - partial success (changes color between red/yellow/green, no cyan/magenta/blue).
    Python - same results

  • AccelGyroMag
    Python - will not run

pi@navio:~/Navio2/Python $ sudo python AccelGyroMag.py
Traceback (most recent call last):
File “AccelGyroMag.py”, line 29, in
import spidev
ImportError: No module named spidev

     *C++ - will not run*

   pi@navio:~/Navio2/C++/Examples/AccelGyroMag $ sudo ./AccelGyroMag -i mpu

   Selected: MPU9250
   Sensor not enabled

Rebooting has not produced any different results.

In addition, we attempted to run ArduCopter-quad, but it doesn’t appear to even start up.

For reference, we completed these setup steps following the Docs instructions:

Docs » Navio2 with APM autopilot » Hardware setup
Attaching Navio2 to a Raspberry Pi (used a Raspberry Pi 2 Model B and provided standoff hardware)
Powering Navio2 (currently powered with microUSB, 5V 1A supply)

No other hardware connections made.

Docs » Navio2 with APM autopilot » Raspberry Pi configuration
Downloading configured Raspbian image
Writing image to SD card
SD card set up with emlid-raspberrypi2-raspbian-navio2-20160212.img.
Configuring Wi-Fi access
Successful, able to SSH via Wi-Fi.

Docs » Navio2 with APM autopilot » APM installation and running
Installing APM

wget 'http://files.emlid.com/apm/apm-navio2_3.3.2-rc2-beta-1.2_armhf.deb' -O apm-navio2.deb
sudo dpkg -i apm-navio2.deb

Running APM

Installed APM Planner from http://ardupilot.com/downloads/?category=35 on both Ubuntu 14.4 and Windows10 machines.

Attempted to run Arducopter with different parameters, but it doesn’t appear to start.
1st attempt

pi@navio:~ $ sudo ArduCopter-quad -A udp:192.168.1.19:14550
Raspberry Pi 2 with BCM2709!
No INS backends available

2nd attempt:

 pi@navio:~ $ sudo ArduCopter-quad
 Raspberry Pi 2 with BCM2709!

Init APM:Copter V3.4-dev (cce4f12e)

Free RAM: 262144
FW Ver: 120

load_all took 13us
/sys/kernel/rcio/adc/ch255 not opened: No such file or directory0 0 0 ▒ Q}▒No INS backends available
HMC5843: Could not detect version
MPU9250: unexpected WHOAMI 0xFF

2

Update:
I found a post that seems to have the same issue:

with a reply

I understand now that the python examples aren’t working.

I tried the cat /sys/kernel/rcio/adc/ch0 command and have consistent readings over 5.2v using a 5V 2A power supply with nothing but a wireless dongle attached.

I was also able to run the C++ example ADC

pi@navio:~/Navio2/C++/Examples/ADC $ ./ADC
A0: 5.2740V A1: 0.0120V A2: 0.0240V A3: 0.0100V A4: 0.0320V A5: 0.0320V
A0: 5.3000V A1: 0.0120V A2: 0.0140V A3: 0.0220V A4: 0.0080V A5: 0.0320V
A0: 5.3000V A1: 0.0120V A2: 0.0140V A3: 0.0220V A4: 0.0080V A5: 0.0320V
A0: 5.3000V A1: 0.0120V A2: 0.0240V A3: 0.0080V A4: 0.0080V A5: 0.0320V
A0: 5.2960V A1: 0.0120V A2: 0.0120V A3: 0.0220V A4: 0.0080V A5: 0.0320V
A0: 5.2960V A1: 0.0120V A2: 0.0240V A3: 0.0100V A4: 0.0320V A5: 0.0320V
A0: 5.3000V A1: 0.0120V A2: 0.0100V A3: 0.0220V A4: 0.0080V A5: 0.0320V
A0: 5.2940V A1: 0.0120V A2: 0.0240V A3: 0.0100V A4: 0.0320V A5: 0.0160V

Still getting same results when trying to run AccelGyroMag.

3

SOLVED: We changed to a different Raspberry Pi 2 and we can now run the example code without errors, happy that the problem was not the Navio2!

4

Good. Also make sure that Navio2 is properly mounted on the RPi with provided screws and spacers, it could have been a lack of contact issue.

5

Hello i’m the university student.

I’m using Navio2 and RaspberryPi 2.
I have same issue about error of absence backend sensors.
While testing my customized code, i get some errors about absene of backend sensors.
and i found out sometimes it gets error in the middle of finding backend sensors like MPU .

I’m not sure the reason, but when i try several times, it outputs error log.

I think there should be constant tests and find out the reason in the long run.
(It could be hardware problem…also)

Thanks.

6

Hi Jung,

Please start a new topic with detailed description of your issue and we will try to help you. It is hard to tell what is the problem by your current description.

7

It’s actually an issue with "MPU9250 :unexpected WHOAMI 0XFF"
I’m not sure what the number of question is,
but the name of question is “MPU9250 :unexpected WHOAMI 0XFF” in this Community forum.

please check it out,
Thanks

8