% Write command to the ThingSpeak server. 
writeApiKey = 'UQ6TMK7Q95VY6DGH';
channelID = 1057217;
thingSpeakURL = 'http://api.thingspeak.com';
thingSpeakWriteURL = [thingSpeakURL '/update'];
fieldName = 'field1';

TurnON=1;
TurnOFF=0;

% Turns LED on:
fieldValue = TurnOFF;
response=webwrite(thingSpeakWriteURL,'api_key',writeApiKey,fieldName,fieldValue);