Different Data Rate of USB HID High Speed (USB 2.0 Device) on USB 2.0 port and USB 3.0 port RRS feed

  • Question

  • Hello,

    I am developing an application to communicate with a High Speed USB HID device. When connected to a USB 2.0 port on PC the data rate is 8 MB/s and if connected to USB 3.0 port on the same PC (Windows 7) the data rate is 24 MB/s. My question is why isn't the USB 2.0 port polling @ 24 MB/s. 

    A USB Sniffers Images are attached for the device based on the type of port it is attached to. When attached to a USB 2.0 port the report interval is approximately 375Us while attaching the same device to a USB 3.0 port reduces the interval to approximately 125Us.

    1. Image of sniffer file when attached to USB 2.0 port

    Sniffer file for when connected to USB 2.0 Port

    2. Image of sniffer file when attached to USB 3.0 port

    Sniffer file when connected to USB 3.0 Port

    Tuesday, July 26, 2016 7:48 AM