A host-controlled serial bus supporting many device classes.
USB uses a host-controlled tree topology with differential D+/D- lines and descriptors identifying device classes (HID, CDC, mass storage). Speeds from 1.5 Mbit/s to 40 Gbit/s; USB-C supports power delivery up to 240 W. Enumeration assigns addresses.
A USB keyboard enumerates as an HID device.
USB is the standard connector for devices and power, so understanding its roles helps you design devices that work with computers.
A host-controlled serial bus supporting many device classes.
USB is the standard connector for devices and power, so understanding its roles helps you design devices that work with computers.
The host controller, which polls devices and schedules transfers, while the devices respond to requests.
The process where the host discovers a new device, reads its descriptors and assigns an address before the device can be used.
Typical applications include designing a USB device such as a keyboard or a storage stick, powering a small gadget from a USB port and debugging a device that does not enumerate on a host computer.
Study "CAN bus" first (topic 67 of 104 in Electronics & Embedded). It covers the groundwork this topic builds on.
Endpoints and transfer types. VBUS 5 V. On-the-go.
A USB keyboard enumerates as an HID device.
The next topic is "ADC peripherals and sampling", which builds directly on this one.
It is classed as Intermediate in Electronics & Embedded (topic 68 of 104). It is an intermediate topic. Work through the beginner topics in Electronics & Embedded first.
Want to practise? Open the interactive course for quick checks, quizzes, simulations and progress tracking.