CFW Bin Format
CFW(Custom Firmware) has been a part of the Ninebot Scooter scene since its early days.
Firmware updates were previously unencrypted, meaning that CFW was also unencrypted.
The bin format is simply the unencrypted firmware update package that overwrites the area after the bootloader on the STM32/STM8 MCU's.
After Ninebot began encrypting firmware updates with TEA (Tiny Encryption Algorithm), apps like XiaoTea and others allowed legacy bin files to be converted to .enc.bin files.
This format was known as CFW Encoded Bin Format.
CFW generators like the ones from ScooterHacking began delivering zip files containing both bin and encoded bin formats.
This was the Zip V1 format.
Nothing special is needed to create these bin files, they are simply the raw firmware that's executed on the chip.
If you have a zip file, you can extract it to see FIRM.bin.
Files in this format are incomplete, they are missing the bootloader.
You can flash by encoding/making it into a zip and using ScooterHacking Utility or another 3rd party flashing app.
STLinking this file format will likely brick your vehicle.