mirror of https://github.com/ARMmbed/mbed-os.git
511b46de83
Happy Gecko's USB Low Energy Mode does not work properly with isochronous endpoints. Note that Happy Gecko errata USB_E112 states: Do not use the SUSPEND mode of LEMOSCCTRL in USB_CTRL. In rare cases with high data throughput, a transmission can fail when this mode is enabled. Use the GATED mode of LEMOSCCTRL for the best energy efficiency. The NONE mode can be used to disable energy savings However, even using GATE mode causes problems for high-frequency isochronous transfers. The primary effect for OUT endpoints is that the first read will succeed, and the following one (targetting the next frame) will fail with zero bytes incoming data, and PKTDRPSTS is set in the related interrupt status register. Disabling LEMOSCCTRL (set to NONE) solves the problem. Since this will cause increased energy usage, do this only when an ISOC endpoint is added. |
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| USBAudio | ||
| USBDevice | ||
| USBHID | ||
| USBMIDI | ||
| USBMSD | ||
| USBSerial | ||