How to simultaneously publish the data to multi fields of thingspeak channel from a raspberry pi via code generation deployment using MATLAB code(not via Simulink) .

The method to publish one field(field1) to think speak is given by the John Anderson

% raspberry pi object

r = raspi();

% log file

fid = fopen( 'logFile.log', 'w' );

% write random number to thingSpeak channel

v = rand;

commandStr = [ 'sudo curl -s "https://api.thingspeak.com/update.json?api_key=<your api key here>&field1=' sprintf( '%f', v ) '"' ];

result = system( r, commandStr );

% log command

fprintf( fid, '%s \n', commandStr );

% log result

fprintf( fid, '%s \n', result );

% close log

fclose( fid );

https://www.mathworks.com/matlabcentral/answers/467879-how-do-i-write-to-a-thingspeak-channel-from-a-raspberry-pi-via-code-deployed-using-the-matlab-coder

How to modify it to simultaneously publish the 2 data to 2 fields (field1 and field2) of thingspeak channel .

Answer 1

[Christopher Stapels]

Have a look at the Write Data page. You can append &fieldX=value to add additional fields to an update.