Using mraa on Dragonboard 410c

Products Support DragonBoard410c
#21

I had to build a new system so I have done it with the latest download from the 96boards site. I did the Fastboot files from:

After installing the new OS I did the following:

sudo apt update
sudo apt upgrade
sudo apt install git build-essential swig3.0 python3-dev cmake
git clone https://github.com/intel-iot-devkit/mraa.git
cd mraa
mkdir build
cd build/
cmake -DBUILDSWIG=ON \
      -DBUILDSWIGPYTHON=ON \
      -DBUILDSWIGNODE=OFF \
      -DBUILDSWIGJAVA=OFF \
      -DCMAKE_INSTALL_PREFIX=/usr \
      ..
make
sudo make install

I have done the tests from above with the following results:

linaro@linaro-alip:~/mraa/build$ uname -a
Linux linaro-alip 4.14.0-qcomlt-arm64 #1 SMP PREEMPT Wed Jan 30 04:14:16 UTC 2019 aarch64 GNU/Linux
linaro@linaro-alip:~/mraa/build$ sudo python3
Python 3.7.3 (default, Apr  3 2019, 05:39:12) 
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import mraa
>>> mraa.getPlatformName()
'DB410C'
>>> mraa.__file__
'/usr/lib/python3.7/dist-packages/mraa.py'
>>> exit()

It seems to be working fine. Are you able to wipe your board and start again?

#22

I won’t be able to wipe my board clean as there are other systems already running on it. Will it help if I cleared the mraa folder and download and build it again? However, if it has anything to do with some configurations already made in the present python then it won’t work I guess

#23

Will it help if I clear the mraa directory and reinstall it and rebuild it?

#24

We have helped you established that the C mraa interface is working on your system and it is only the Python interface that isn’t.
I have established that there is no issue with the Python mraa interface with the latest kernel.
So I think it is over to you to establish what you have done to your system to cause it to fail.
Removing mraa and re-installing seems a sensible next step.
As we cannot reproduce your issue it is difficult for us to help unless you can say what steps we need to take to reproduce your issues

#25

Based on the help received, I removed mraa and re installed it again step-by-step and it’s finally working now. Thank you all.

2 Likes
#26

Hey. I know this issue is closed but I wanted to ask some questions. In using interrupts from the mraa library it calls a function which is the ISR. Now in microcontrollers we have a watchdog due to which we cannot have heavy ISR and can max change flag values. Is it true for this system only?

#27

I compiled mraa from sources.
I tried ‘import mraa’ but it said ‘no module named mraa’

Can we install a prebuilt package? library and python package?