Custom firmware on cheap Xiaomi Thermometer, Bluetooth to Zigbee (2025) #homeassistant #xiaomi

WARNING: some people have reported recently that this fix has bridked their devices. It’s not clear if Xiaomi have updated the hardware to prevent this fix… use with caution!!⚠️ The Xiaomi Bluetooth Temperature and Humidity sensor is awesome, it's low cost, looks good, lasts for ages and is reasonably accurate. There's just one problem, the firmware on new devices (version 2.1.1.0159) is locked down, meaning a Xiaomi account is needed to be able to access your own temperature data - NO THANKS! In this video I show you how to use a USB to UART adapter to flash an intermediate firmware on to the device, this then allows you to flash the latest Zigbee firmware Over the Air (OTA), which is really sweet. Once completed, the thermometer can be easily added to Home Assistant using ZHA. To do this you'll need an appropriate USB to UART adapter, I used this one: USB to TTL Adapter USB to Serial Converter – Genuine FTDI USB UART IC FT232RL 🔗Click & Buy: https://s.click.aliexpress.com/e/_onMDXLv For a full walk through, check out my blog: https://circuithelper.com/hacking-the-xiaomi-mijia-bluetooth-thermometer-2/ The files you need are here, first download ATC_ota_40000.bin: https://github.com/devbis/z03mmc/releases/download/1.1.0/ATC_ota_40000.bin Install it using this web page: https://pvvx.github.io/ATC_MiThermometer/USBCOMFlashTx.html Next download the z03mmc.bin firmware: https://github.com/devbis/z03mmc/releases/download/1.1.0/z03mmc.bin Install it OTA using this web page: https://devbis.github.io/telink-zigbee