Depending on the device, a confusing number of methods can exist for flashing and upgrading the firmware. Here is provided a general overview of some of the methods.
Tip
Flashing for a specific device is described in more depth on the hardware specific pages, please check those out for step by step instructions.
Important
Firmware with version numbers which end in a odd number (like v1.3.05) are developer versions (dev versions in slang). You should not use them unless you understand clearly what this implies. Firmware versions which end in an even number are safe to use (like v1.3.00 or v1.3.04).
The easiest way to flash firmware is the mLRS Web Flasher app.
Tip
It is strongly recommended to use this tool.
The STM32CubeProgrammer is the go-to tool for flashing STM32 devices. Any STM32 based mLRS device can be flashed by at least one of the three protocols, UART, DFU mode via USB, or STLink via SWD.
Note
Sometimes one can find the "ST-LINK Utility" software being suggested. This software is totally outdated, and fully replaced by STM32CubeProgrammer. Please use STM32CubeProgrammer.
The STM32CubeProgrammer can be downloded from ST's website: https://www.st.com/en/development-tools/stm32cubeprog.html. If you have installed the STM32CubeIDE for building/compiling the firmware yourself, it is usually included already.
In many cases a STLink programmer is needed for flashing STM32 devices. It might be tempting to buy one of the cheap STLink/V2 clones, but these may cause issues or may not even work. The STLINK-V3MINIE is a genuine inexpensive STLink/V3 programmer from STMicroelectronics, which can be recommended.