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HV UPDI Programmers for tinyAVR® 0-1 series MCUs and Arduino

What are HV UPDI Programmers?

The tinyAVR® 0 series and 1-series are programmed through the Unified Program and Debug Interface (UPDI) that uses the UPDI/reset pin. This pin is both multi-functional and high voltage tolerant. If configured as Reset or GPIO, a 12V enable sequence is needed to place it in UPDI mode to allow programming.

The HV UPDI programmers here are open source hardware and work with the megaTinyCore , DxCore or megaCoreX and the Arduino IDE. They're low cost, easy to use and don't interfere with the normal workflow in Arduino.

What makes this special?

A HV programmer will open up possibilities for utilizing the UPDI/Reset/GPIO pin (PA0) in your design for various purposes, while alleviating the fear of getting locked out from the MCU.