Q. How do you flash a bin file for a firmware update or the like to a USB?
A. You don’t need to ‘flash it’ although some explainers will tell you to do this. Older hardware will use different filesystems such as FAT32 or EXT3 (or another version) as they may be based on a Linux-type operating system rather than Windows.
Simply format your USB stick to FAT32 and then copy the .BIN file onto the stick – that may work.
Don’t forget you might need to format your stick back to NTFS or newer afterwards if you want to use it for other things as FAT32 has a limit on filename length and filesizes.