The compass uses the device’s magnetometer to give a heading reading between 0 – 360. Note that this value is only accurate when the device is relatively flat. There is no control over update rate; updates are received whenever the device perceives a change in orientation.

Additional JSON Attributes

• onvaluechange – this event handler is called after the magnetometer has been read but before its value it outputted.

Simple JSON

{
    "name":"comp", "type":"Compass",
    "protocol":"local",
    "min":0, "max":1,
},

Extra JSON

{
    "name":"comp", "type":"Compass",
    "onchange":"compLabel.changeValue(this.value);",
    "protocol":"local",
    "min":0, "max":1
},