Particle core/photon/electron function post data using curl or wget

Particle core/photon/electron function post data using curl or wget

This is a quick howto on using curl, wget or any other web based method to pass data to a Particle (formerly Spark) Core, Photon or Electron.

  • working Particle device as listed above
  • software on the device waiting for user passed data
  • The device’s access token

A simple code example which exports a function is below.

int ledPin = D7; //D7 on Particle devices has an attached LED
int lastLedStatus = LOW;

void setLed(int ledStatus)
    digitalWrite(ledPin, ledStatus);
    lastLedStatus = ledStatus;

    The function labbyFunc() receives data from the internet and can act on it.
    It returns a value that can be parsed by your HTTP client.
    Return values:
    0 LED is off (off)
    1 LED is on (on)
    2 LED was off, now it is on (toggle)
    3 LED was on, now it is off (toggle)
    4 unrecognised command
int labbyFunc(String command)
    if(command.toLowerCase() == "off")
        return 0;
    else if(command.toLowerCase() == "on")
        return 1;
    else if(command.toLowerCase() == "toggle")
        setLed(HIGH - lastLedStatus);
        if(lastLedStatus == HIGH)
            return 2;
            return 3;
        return 4;

void setup()
    Particle.function("labbyFunc", labbyFunc);
    pinMode(ledPin, OUTPUT);

void loop()
    //There is nothing to see here, all the work is done in the labbyFunc function
    //whenever it receives data.

For the remote side we can use the HTTP POST method of talking to the device such as a web browser (using a form), curl or wget.
We need some information before we can send the request, deviceID and accesstoken.
deviceID can be found in the Devices section of the Particle build page
accesstoken can be found in the Settings section


curl -d labbyFunc="ON" -d access_token="accesstoken"


wget -q --post_data="labbyFunc=ON&access_token=accesstoken"

Errors and their solutions:
{“ok”:false,”error”:”Variable not found”}
Are you trying to send the data using GET eg ?labbyFunc=on – if so use POST.
If you have forgotten the function name you can get the function list using{deviceID}?access_token={accesstoken}

If you need any help just drop a message in the comments and I will get back to you.

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