USBFXStack Middleware Library v1.3.2

See the README.md and the USBFXStack API Reference Manual for a complete description of the USBFXStack.

Feature updates

• USB API changes

  • Added a Cy_USBD_ControlUsb2Support() API, which allows the fallback from USB 3.x connection to USB 2.x to be disabled. A callback function can be registered with the type of CY_USB_USBD_CB_USB3_LINKFAIL to get notified when USB 3.x link initialization has failed and fallback to USB 2.x is disabled
  • Added a Cy_USBD_GetDeviceStats() API to get a count of USB link recovery cycles that have taken place
  • Updated the USBD stack so that USB 3.x re-connection attempt after a USB 2.x bus reset is done from the stack task instead of directly from the timer callback. This resolves a potential race condition between operations performed in USB application callbacks and the link re-initialization done by the stack.

• LVDS API changes

  • Implemented a firmware-based PHY training sequence, which is a more robust alternative to the default training performed by the LVDS block. The firmware-based training scheme can be enabled by calling the Cy_LVDS_CustomTraining_Select() function with the customTrainEn parameter set to true, before the LVDS block is initialized by calling Cy_LVDS_Init() or Cy_LVDS_InitExt().
    
    If the firmware-based training is enabled, the state machine will take over and complete the training at the end of the Cy_LVDS_PhyTrainingStart() call. The state of the training task can be monitored using the Cy_LVDS_CustomTraining_Task() function. The FPGA LVDS transmitter needs to keep sending the PHY training pattern on all data and control lanes until this training process is completed.
    
    Use of the firmware-based training process is recommended to ensure that the LVDS receiver works correctly and receives all data properly after the training process.
  • Added an Cy_LVDS_OverridePhyTraining() API, which allows the results of the LVDS PHY training to be overridden with a static sampling delay value to be used

Defect fixes

• Updated the Cy_Debug_LogDeInit() function to properly shut down the USBFS port if it is used for logging
• Updated DataWire DMA configuration to resolve intermittent throughput drop seen in a few USB 2.x use cases
• Updated endpoint flush and reset functions to resolve corner case failures
• Updated the Cy_USBSS_Cal_GetBusOrientation() function to avoid errors due to ongoing USB-PD communication

Known issues and limitations

None.

Supported software and tools

This version of the USBFXStack Middleware Library is validated for the compatibility with the following software and tools:

Software and tools	Version
ModusToolbox™ software environment	3.5.0
CAT1A Peripheral Driver Library (PDL)	3.18.0
FreeRTOS for Infineon MCUs	10.5.004
GCC Compiler	14.2.1
Arm® Compiler	6.22

More information

For more information, see the following documents:

• USBFXStack Middleware README.md

• USBFXStack API Reference Manual

• ModusToolbox™ software environment, quick start guide, documentation, and videos

• Infineon Technologies AG

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