IoT Microchip AVR Programmer based on TPI and PDI Protocols for Firmware-over-the-Air Updates

The smart connected devices which form the IoT Wireless Sensor Networks (WSN) need to be remotely re- programmed over-the-air. Therefore, new features are added, software bugs or security vulnerabilities are fixed and their assigned applications can be re-purposed. This paper proposes an IoT FOTA Microchip AVR Programmer using Wi-Fi tech- nology which supports the official Microchip Tiny Programming Interface (TPI) and Program and Debug Interface (PDI). TPI is supported by the Microchip AVR ATtiny family and PDI is supported by the Microchip AVR ATxmega family of micro- controllers. The core contribution is to add wireless connectivity to the official standard STK500v2 and STK600 programming protocols of the Microchip AVR Programmer. A simulation is conducted using the AVRDUDE Command-Line and the NB Virtual Comm Port applications proving reliable FOTA proce- dure. Experimental implementation is carried on the Microchip AVR ATtiny20 and ATxmega32A4U micro-controllers, and the collected results showed a significant match to the conducted simulation.