Python UPDI driver for programming "new" tinyAVR devices
pyupdi is a Python utility for programming AVR devices with UPDI interface using a standard TTL serial port.
Connect RX and TX together with a suitable resistor and connect this node to the UPDI pin of the AVR device.
Be sure to connect a common ground, and use a TTL serial adapter running at the same voltage as the AVR device.
Vcc Vcc +-+ +-+ | | +---------------------+ | | +--------------------+ | Serial port +-+ +-+ AVR device | | | +----------+ | | | TX +------+ 4k7 +---------+ UPDI | | | +----------+ | | | | | | | | | RX +----------------------+ | | | | | | | +--+ +--+ | +---------------------+ | | +--------------------+ +-+ +-+ GND GND