Recently, Microchip Technology has introduced a new interface for external programming and on-chip debugging of tinyAVR, megaAVR, and AVR-Dx families of microcontrollers, which is called; Unified Programming and Debug Interface (UPDI). It is a successor to the Programming and Debug Interface (PDI) which physically depends on two wires and exists on all microcontrollers of the AVR XMEGA family. UPDI provides microcontrollers programming and debugging via a bi-directional half-duplex asynchronous communication using a single-wire interface. This paper proposes an IoT Microchip AVR programmer which supports UPDI using Wi-Fi and LoRa technologies. It provides over-the-air firmware updating to the supported families of microcontrollers. A simulation is performed using the AVRDUDESS desktop application showing successful OTA firmware updating. Experimental work is conducted on a Microchip AVR ATtiny3216 microcontroller, and the results proved a match to the carried-on simulation.