Need help on a project

[morind79]

Hi everybody,

I am developping a project and alone it is not easy because I miss some time and knowledge...
Anyway I present my project, this is mainly domotic, but can be used for several things.

First of all a link : https://github.com/morind79/wiringOli

I have created a board you plug on the A20 board (You can see on pictures)
This board adds I/O compatible either with 3.3V or 5V, you can choose.
You have also a display, GSM module, CAN Bus, XBee, RS232.

I started to create a library in C to easily program the board, but it is still in progress.
The purpose is to create a Java layer. In fact I would like to do the same as wiringPi/Pi4j (See web site of these projects)

I need people that are interested in this project to help me do the C programming.

Thank you

Best regards
Denis

[dave-at-axon]

Nice design work you have there. Looks like you used Altium Designer?

I also created a carrier board but it has the A20 sitting above it with ribbon cable connections as I have a 6600mAh battery and another interface PCB under it too. It has ADC, DAC and digital IO etc. Works great.

I am curious to why you chose the MCP2515 for CAN bus when the A20 has a built in CAN controller?

I decided to run Android with it and created a JNI to access the I2C and GPIO. CAN bus is a work in progress.

[morind79]

Hi Dave,

Yes I used Altium ;-)
Well I started on Linux this is the reason why I am using it, but maybe this will be easier to use Android, I do not know really, I would like to see your code to manage I/O, I2C...

Concerning the DAC I know there is one available in the A20, but it seems pins are not available, or I am wrong ?

Br
Denis

[dave-at-axon]

As I needed a couple of 4-20mA outputs I used an external I2C DAC from Maxim and this is driven through an isolated driver to keep the 4-20mA GND separate.

I am busy re-writing the driver to make it a library as currently it is part of the project. I'll put it up on GITHUB once it is done. It will support GPIO and I2C.

I am also considering Linux and trying to get remote debugging with QT working on an A10S and if that works I will put in effort to learn Embedded Linux and switch to that for future development. Android has been good but suffers from being a mobile OS so has a tendency to shutdown apps after they have been running for some time. I have managed to "trick" it a little but you need to create a service to make it work. It can still shutdown the visual part which is annoying but at least the part that is processing the data and handling the IO is now in a service, that part still works.

With Linux I won't have that issue and it would be nice to gain some new knowledge at the same time. Learning is still great fun at my age

[morind79]

Some news, I have this working :

I/O
I2C
LCD display on I2C
7 segments display

What is not yet done is :

CAN Bus
RS232
XBee
GSM

I will be very happy to have people sharing this project :-)

Best regards
Denis