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CherryUSB

中文版

CherryUSB is a tiny, beautiful and portable USB host and device stack for embedded system with USB IP.

CherryUSB

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)

Easy to use USB

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:

  • Equivalent to using uart tx dma/uart rx dma
  • There is no limit to the length of send and receive, the user does not need to care about the USB packetization process (the porting driver does it)

Easy to bring out USB performance

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
  • Packetization is handled in interrupt

Directory Structure

Directory Description
class usb class driver
common usb spec macros and utils
core usb core implementation
demo usb device and host demo
osal os wrapper
platform class support for other os
docs doc for guiding
port usb dcd and hcd porting
tools tool url

Device Stack Overview

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)
  • Support Human Interface Device (HID)
  • Support Mass Storage Class (MSC)
  • Support USB VIDEO CLASS (UVC1.0、UVC1.5)
  • Support USB AUDIO CLASS (UAC1.0、UAC2.0)
  • Support Device Firmware Upgrade CLASS (DFU)
  • Support USB MIDI CLASS (MIDI)
  • Support Remote NDIS (RNDIS)
  • Support WINUSB1.0、WINUSB2.0、WEBUSB、BOS
  • Support Vendor class
  • Support UF2
  • Support Android Debug Bridge (Only support shell)
  • Support multi device with the same USB IP

CherryUSB Device Stack resource usage (GCC 10.2 with -O2):

file FLASH (Byte) No Cache RAM (Byte) RAM (Byte) Heap (Byte)
usbd_core.c ~4400 512(default) + 320 0 0
usbd_cdc_acm.c ~400 0 0 0
usbd_msc.c ~3800 128 + 512(default) 16 0
usbd_hid.c ~360 0 0 0
usbd_audio.c ~1500 0 0 0
usbd_video.c ~2600 0 84 0
usbd_rndis.c ~2100 2 * 1580(default)+156+8 76 0

Host Stack Overview

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.

CherryUSB Host Stack has the following functions:

  • Support low speed, full speed, high speed and super speed devices
  • Automatic loading of supported Class drivers
  • Support blocking transfers and asynchronous transfers
  • Support Composite Device
  • Multi-level HUB support, expandable up to 7 levels(Testing hub with 10 ports works well,only support dwc2 and ehci now)
  • Support Communication Device Class (CDC_ACM, CDC_ECM)
  • Support Human Interface Device (HID)
  • Support Mass Storage Class (MSC)
  • Support USB Video CLASS (UVC1.0、UVC1.5)
  • Support USB Audio CLASS (UAC1.0)
  • Support Remote NDIS (RNDIS)
  • Support USB Bluetooth class (support nimble and zephyr bluetooth stack, support CLASS:0xE0 or vendor class like cdc acm)
  • Support Vendor class (serial, net, wifi)
  • Support USB modeswitch
  • Support Android Open Accessory
  • Support multi host with the same USB IP

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):

file FLASH (Byte) No Cache RAM (Byte) RAM (Byte) Heap (Byte)
usbh_core.c ~9000 512 + 8 * (1+x) *n 28 raw_config_desc
usbh_hub.c ~6000 32 + 4 * (1+x) 12 + sizeof(struct usbh_hub) * (1+x) 0
usbh_cdc_acm.c ~900 7 4 + sizeof(struct usbh_cdc_acm) * x 0
usbh_msc.c ~2700 64 4 + sizeof(struct usbh_msc) * x 0
usbh_hid.c ~1400 256 4 + sizeof(struct usbh_hid) * x 0
usbh_video.c ~3800 128 4 + sizeof(struct usbh_video) * x 0
usbh_audio.c ~4100 128 4 + sizeof(struct usbh_audio) * x 0
usbh_rndis.c ~4200 512 + 2 * 2048(default) sizeof(struct usbh_rndis) * 1 0
usbh_cdc_ecm.c ~2200 2 * 1514 + 16 sizeof(struct usbh_cdc_ecm) * 1 0
usbh_cdc_ncm.c ~3300 2 * 2048(default) + 16 + 32 sizeof(struct usbh_cdc_ncm) * 1 0
usbh_bluetooth.c ~1000 2 * 2048(default) sizeof(struct usbh_bluetooth) * 1 0

Among them, sizeof(struct usbh_hub) and sizeof(struct usbh_hubport) are affected by the following macros:

#define CONFIG_USBHOST_MAX_EXTHUBS          1
#define CONFIG_USBHOST_MAX_EHPORTS          4
#define CONFIG_USBHOST_MAX_INTERFACES       8
#define CONFIG_USBHOST_MAX_INTF_ALTSETTINGS 8
#define CONFIG_USBHOST_MAX_ENDPOINTS        4

x is affected by the following macros:

#define CONFIG_USBHOST_MAX_CDC_ACM_CLASS 4
#define CONFIG_USBHOST_MAX_HID_CLASS     4
#define CONFIG_USBHOST_MAX_MSC_CLASS     2
#define CONFIG_USBHOST_MAX_AUDIO_CLASS   1
#define CONFIG_USBHOST_MAX_VIDEO_CLASS   1

USB IP Support

Only standard and commercial USB IP are listed.

IP device host Support status
OHCI(intel) none OHCI
EHCI(intel) none EHCI
XHCI(intel) none XHCI
UHCI(intel) none UHCI ×
DWC2(synopsys) DWC2 DWC2
MUSB(mentor) MUSB MUSB
FOTG210(faraday) FOTG210 EHCI
CHIPIDEA(synopsys) CHIPIDEA EHCI
CDNS2(cadence) CDNS2 CDNS2
CDNS3(cadence) CDNS3 XHCI ×
DWC3(synopsys) DWC3 XHCI ×

Documentation Tutorial

Quickly start, USB basic concepts, API manual, Class basic concepts and examples, see CherryUSB Documentation Tutorial

Video Tutorial

USB basic concepts and how the CherryUSB Device stack is implemented, see CherryUSB Device Stack Tutorial.

Graphical Config Tool

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
Bouffalolab BL702/BL616/BL808 bouffalolab/ehci bouffalo_sdk <= latest Long-term
ST STM32F1x fsdev stm32_repo <= latest Long-term
ST STM32F4/STM32H7 dwc2 stm32_repo <= latest Long-term
HPMicro HPM6000/HPM5000 hpm/ehci hpm_sdk <= latest Long-term
Essemi ES32F36xx musb es32f369_repo <= latest Long-term
Phytium e2000 pusb2/xhci phytium_repo >=1.4.0 Long-term
Artinchip d12x/d13x/d21x aic/ehci/ohci luban-lite <= latest Long-term
Espressif esp32s2/esp32s3/esp32p4 dwc2 esp32_repo <= latest Long-term
NXP mcx kinetis/chipidea/ehci nxp_mcx_repo <= latest Long-term
Kendryte k230 dwc2 k230_repo v1.2.0 Long-term
AllwinnerTech F1C100S/F1C200S musb cherryusb_rtt_f1c100s <= latest the same with musb
Bekencorp bk7256/bk7258 musb bk_idk v0.7.0 the same with musb
Sophgo cv18xx dwc2 cvi_alios_open v0.7.0 TBD
WCH CH32V307/ch58x ch32_usbfs/ch32_usbhs/ch58x wch_repo <= v0.10.2 TBD
Raspberry pi rp2040 rp2040 pico-examples <= v0.10.2 No more updated

Package Support

CherryUSB package is available as follows:

Commercial Support

Refer to https://cherryusb.readthedocs.io/zh-cn/latest/support/index.html.

Contact

CherryUSB discord: https://discord.com/invite/wFfvrSAey8.

Company Support

Thanks to the following companies for their support (in no particular order).