Using Raspberry Pi SPI interface from Simulink

Hello,

I found this example for collecting analog data with a Raspberry Pi and an MCP3008. It works great in the MATLAB command window. However, I'd love to be able to do the same thing in Simulink. I've tried using a MATLAB Function block in Simulink, however I can't seem to get it to pass the mcp3008 parameter into the function. I've made it a global variable and I've tried to use a To Workspace block and neither seem to work. It seems like a waste of resources to start and stop the connection to the Raspberry Pi on each Simulink iteration.

Does anyone have any ideas on how to make this work?

Thank you, Rebecca

Answer 1

[Pjer]

maybe some command in s-function is not supported,so what you need id SPI-driver which read from analog signal.You may like this: SPI driver

Answer 2

[mprice]

Try using the WiringPi library, found here: WiringPi

It contains c code to access various Raspberry Pi capabilities, including SPI. You can implement it in an s-function or the s-function builder as long as you're including the right headers and have the library available in your working directory. You also want to make sure that the code is stored on the Pi itself as well, and make sure that “-lwiringPi” is included in the linker flags in the Simulink makefile.

[Alex83]

Hi! I also have this problem...for newbies it is hard to find a step-by-step instruction how to implement wiringpi in simulink and the rpi device. Is there a chance that you could help me with a short step-by-step tutorial imagining that there is a blank Matlab 2016 version only with RPI support package installed? What do I do next? Kind regards, Alex

Answer 3

[Alex83]

By the way, when I am trying to run Rebecca's example, I get always a very long error message starting with:

Error executing command "touch -c /home/pi/untitled_ert_rtw/.*;make -f untitled.mk all -C /home/pi/untitled_ert_rtw". Details:*

What do I do wrong?

[Fernando Lima Saraiva Filho]

Hello Alex83. I have the same message of error in another problem. Did you find a solution for this? Thanks in advance. Fernando.

[Morteza aliyari]

hi,i have same problem like Alex83. i can't use any wiringPi functions on s_function in matlab 2017a simulink. i add wiringPi to rpi3b too.but error didn't change. Anyone can help?

Answer 4

[Jhon Ardilla]

¿Alguien pudo encontrar la solución?