Real-time USB host software stack for embedded systems equipped with a USB host or OTG controller.



Key Features

Thanks to a hardware abstraction layer, you can easily port Cs/USB software to any new USB devices by simply modifying existing hardware access routines.

Small footprint

• High performance

• Use with commercial or proprietary RTOS

• Easy-to-use API

• Support for external hubs

• Extensive test cases and test harness to verify stack integration


Class Support

USB Host Classes

Cs/USBH module includes CDC-ACM, HID, MSC, and FTDI class drivers.

Class Communicate with Devices Such As
Communications Device Class Abstract Control Model (CDC ACM)
  • USB Modems
  • USB-to-serial adapters
Human Interface Device (HID)
  • Keyboards
  • Mice
  • Vendor-specific HID devices
Mass Storage Class (MSC)
  • Flash drives
  • Hard disk drives
  • CD/DVD drives
FTDI Class


Driver Support

USB Host Controllers

Cs/USBH module provides USB device controller support for the following hardware architectures: 

Driver Examples of Platform
  • Atmel SAM series
  • NXP LPC2468
  • Texas Instruments RM series
  • Atmel SAM series
  • NXP LPC, Kinetis, i.MX series
  • Xilinx Zynq series
  • Renesas RX series

Renesas USBHS

  • Renesas RX64, RX71, RZ, SH series
  • ST Microelectronics STM32F series
  • ST Microelectronics STM32F series
  • Microchip ATSAM D5x/E5x

 If you don’t see the driver you are looking for please contact us. We can give you the latest information on drivers we have available.


Commercial License

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Technical Support

Technical Support Plan

Technical support services for any of the Cs/ software is readily available to all customers currently using or interested in the Cs/ family of RTOS components.

If you are currently without technical support for the Cs/OS software don’t go at it alone. Please contact us to learn how our Cs/OS product experts, with years of embedded software experience, can save you valuable engineering time and money.

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Consulting Services

Specialized Engineering Services

Do you need specialized assistance with your Cesium-based embedded project? Do you need real-time embedded software expertise for your mission critical application? For these or any other embedded software projects, help is available via our Consulting Services that are tailored to your unique needs. Please contact us with your requirements to learn how we can quickly deliver our expertise to your team.

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Cesium software includes comprehensive documentation, full source code, powerful debugging features, and support for a huge range of CPU architectures.


Cesium software offers unprecedented ease-of-use, a small memory footprint, remarkable energy efficiency, and all with a full suite of protocol stacks.


Engineers across the world building industrial controls, medical devices, and aerospace systems know they can rely on Cesium software for the foundation of exceptional products.