For now, the STM60 series uses this bootloader, which is free of charge (using the HIDUSB driver that comes with the system).

Basically, according to the corresponding instructions of the keyboard, when the specified button is inserted at the same time, the USB cable is inserted, and the firmware mode is entered.

There may be some problems during the brushing process. such as:

Unplug the USB cable and re-enter the flash mode to ensure it is recognized. And the name displayed in the device after recognition is as follows:

If the firmware is not normal, refer to the instructions in BootHID, check the driver, check the driver of the following device, let the device enter the firmware mode to find it.

As shown in the figure below, after the normal refresh is completed, it will display OK. At this time, if you can't recognize the keyboard after re-plugging the USB, you can re-flash the firmware again. It may be that the firmware is not complete or the firmware itself has a problem.