The Intel® Joule™ module is equipped with multiple USB ports to enable various types of communication protocols. Type-A, micro-Type-B and Type-C connectors are made available on one side of the expansion board. While there is only one Type-A connector, utilizing a powered USB hub will allow you to incorporate more than 1 Type-A USB connection for things like mouse, keyboard, or thumb drive.
From a hardware perspective, the USB sub-system supports one DRD (dual-role device)/OTG (on-the-go) port, which uses separate host controller (xHCI) and device controller (xDCI) IPs.
USB 3.0 - one host only, and one OTG (host or device)
Max USB 3.0 Speed - 5 Gb/s
USB 2.0 - two host only, and one OTG
Max USB 2.0 Speed - 480 Mb/s
Connected USB devices are immediately identified by the OS by gadget detection on the USB connectors. Once a USB device is detected, its information is parsed into a G1 directory where a device template records the device’s information (such as idVendor and idProduct) and working parameters (such as default language or serial number). Function instances are also created and bound to the configuration. Available UDC drivers are then verified and the newly created gadget device is attached to the UDC driver. Finally, the configuration instances created are linked to the respective devices and an IP address is assigned.
Minicom is a text-based serial port communication program that enables users to verify their connections. Install using the following command:
$ sudo apt-get install minicom
Additionally, you can verify the system recognizes your adapters by running the following command:
$ dmesg | grep tty
All USB port types can be listed by running this command:
Each bus and device will be listed.