How to access RaspberryPi I2c in Simulink

Is there a way to access the i2c bus on a Raspberry Pi with the new support package in Simulink? I dont see any straightforward way of doing it.

Answer 1

[Murat Belge]

There are no Simulink blocks to access I2C bus in the Raspberry Pi support package. However, that does not mean you can't do it. Using MATLAB function blocks, you can call Linux command line utilities i2cset and i2cget to read and write to the I2C bus. Someone used this approach to access the GPIO pins back when GPIO was not supported. Here is the link to the MATLAB FEX entry: http://www.mathworks.com/matlabcentral/fileexchange/38508-access-gpio-pins-on-beagleboard-from-simulink.

There is a multitude of references in Internet on how to use i2cset and i2cget functions. Before being able to use these, you need to install i2c-tools package on Raspbian Wheezy (run "sudo apt-get update; sudo apt-get install i2c-tools" on Linux shell to install). Here is a tutorial: https://www.ridgerun.com/developer/wiki/index.php/Developing_a_Linux_driver_for_a_chip_with_I2C_registers

Answer 2

[utya]

hello. So i use i2cset and i2cget functions to recieva data from IMU. I use this code http://www.mathworks.com/matlabcentral/fileexchange/38508-access-gpio-pins-on-beagleboard-from-simulink

function y = fcn() 
%#codegen 
persistent pf; 
pf = coder.opaque('FILE *'); 
y = coder.nullcopy(uint8(0)); 
res = coder.nullcopy(uint8(zeros(1, 10))); 
readOnly = c_string('r'); 
readCmd = c_string(['i2cget -y 1 0x53 0x32']); 
if isequal(coder.target, 'rtw') 
    pf = coder.ceval('popen', coder.rref(readCmd), coder.rref(readOnly)); 
    coder.ceval('fgets', coder.wref(res), 10, pf); 
    coder.ceval('printf', c_string('%s'), c_string(res));

end 

end 

function str = c_string(str) 
% Convert MATLAB string to C-string by adding a string termination 
% character 
str = [str, 0]; 
end

But i dont know how to send data to Scope. Please help me.

Answer 3

[Lennart]

Hi there,

I was wondering whether anyone might know something like the i2cset and i2cget functin for I2S. Is there anything like that for a linux on a chip? Can't really find anything in combination with simulink :/

Answer 4

[Mirko]

Hi, I am a new user of Matlab/Simulink, for the first time, I would like to make a connection between a raspberry pi I2C and an Arduino using simulink. Someone could explain how this code and where do I pick up the data read?

There is a place in simulink Sfunction that creates a connection with I2C read and write?