This is wireless, battery operated, temperature transmitter. The wireless temperature sensor is configured to transmit a temperature reading every 5 minutes. The device sleeps in between transmission in order to save battery power and is awoken every 5 minutes by an internal timer. This allows the device to be used for around 1 year on a single coin cell battery. The transmission interval can be configured between 1 minute and 999 minutes. If powered externally then the device can operate in a fully awake mode and temperature readings can be requested from the sensor in a request/reply fashion.