Where does Bootloader for STM32G0B1M1 look for a USB cable? My previous question was how to detect a USB cable, but the answer was just use VBUS and an EXTI to detect. Which interrupt does the bootloader monitor for a cable?

[SMoor.1]

My previous question was how to detect a cable and they said to use a EXTI to receive a VBUS detection. The customer wants to use USB to program a blank device (so nothing configured) and EXTI is a block of interrupts and could be multiple pins. Please provide more details on how the bootloader checks for a USB cable.

Thanks,

Sonya

[Tesla DeLorean]

I think they can monitor voltage levels on the DP/DM pins at the USB IO Cell​.

Unconnected state determined by pull-ups.​

[MM..1]

Read AN2606

[SMoor.1]

I have read AN2606, but it does not tell you how the bootloader detects that a USB cable is detected. We know how to detect a USB cable is connected, but can't find details on how the bootloader recognizes the connection.

[MM..1]

For what you need it. System bootloader or any other use USB standart for init communication.

I use it two way. One is device powered .. connect USB cable .. reset MCU with boot0 pin ...

Second not powered device , schematics that pull power from USB and set boot0 pin

and exist more ...