There are 3 USB connectors on the SOM-BSB and STM32MP1-BSB boards.
The USB connectors P3 (miniUSB on SOM-BSB) and J10 (USB-C on STM32MP1-BSB) are used to provide power and expose two STM32MP1 UART interfaces. This connector should be used to power the board and access Linux console.
The USB OTG connectors P5 (miniUSB on SOM-BSB) and P5 (microUSB on STM32MP1-BSB) can be used to attach any USB devices to the board and also to attach the board to a host computer.
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The P4 USB-A connector on both the SOM-BSB and STM32MP1-BSB is used to attach any USB devices to the board. E.g., when a USB Flash is attached to the board, the system detects it as follows:
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