CherryUSB is a tiny, beautiful and portable USB host and device stack for embedded system with USB IP.
## Why choose
### Easy to study USB
In order to make it easier for users to learn USB basics, enumeration, driver loading and IP drivers, the code has been written with the following advantages:
- Lean code, simple logic, no complex C syntax
- Tree-based programming with cascading code
- Class-drivers and porting-drivers are templating and simplification
- Clear API classification (slave: initialisation, registration api, command callback api, data sending and receiving api; host: initialisation, lookup api, data sending and receiving api)
In order to facilitate the use of the USB interface and to take into account the fact that users have learned about uart and dma, the following advantages have been designed for the data sending and receiving class of interface:
Taking into account USB performance issues and trying to achieve the theoretical bandwidth of the USB hardware, the design of the data transceiver class interface has the following advantages:
- Porting drivers directly to registers, no abstraction layer encapsulation
- Memory zero copy
- If IP has DMA then uses DMA mode (DMA with hardware packetization)
- Unlimited length make it easier to interface with hardware DMA and take advantage of DMA
CherryUSB Device Stack provides a unified framework of functions for standard device requests, CLASS requests, VENDOR requests and custom special requests. The object-oriented and chained approach allows the user to quickly get started with composite devices without having to worry about the underlying logic. At the same time, a standard dcd porting interface has been standardised for adapting different USB IPs to achieve ip-oriented programming.
CherryUSB Device Stack has the following functions：
- Support USB2.0 full and high speed, USB3.0 super speed
- Support endpoint irq callback register by users, let users do whatever they wants in endpoint irq callback.
- Support Composite Device
- Support Communication Device Class (CDC_ACM, CDC_ECM)
The CherryUSB Host Stack has a standard enumeration implementation for devices mounted on roothubs and external hubs, and a standard interface for different Classes to indicate what the Class driver needs to do after enumeration and after disconnection. A standard hcd porting interface has also been standardised for adapting different USB IPs for IP-oriented programming. Finally, the host stack is managed using os, and provides osal to make a adaptation for different os.
The CherryUSB Host stack also provides the lsusb function, which allows you to view information about all mounted devices, including those on external hubs, with the help of a shell plugin.
CherryUSB Host Stack resource usage (GCC 10.2 with -O2):
Quickly start, USB basic concepts, API manual, Class basic concepts and examples, see [CherryUSB Documentation Tutorial](https://cherryusb.readthedocs.io/)
## Video Tutorial
USB basic concepts and how the CherryUSB Device stack is implemented, see [CherryUSB Device Stack Tutorial](https://www.bilibili.com/video/BV1Ef4y1t73d).
## Graphical Config Tool
[chryusb_configurator](https://github.com/Egahp/chryusb_configurator) is written in **electron + vite2 + ts** framework，currently used to automate the generation of descriptor arrays, with additional functionality to be added later.
## Demo Repo
| Manufacturer | CHIP or Series | USB IP| Repo Url | Support version | Support status |
