Increasing USB endpoint siize on the MCBSTR9 board

Hi all,

I have the MCBSTR9 board and working with the USB peripheral. I have integrated the USB HID example and is capable of communicating from the PC to device and vice versa. One thing that is troubling is that I've looked over the ST Micro data sheet for the STR91xFA and the USB endpoint packet buffer size can be bigger than 64 bytes. So my question is how can I increase the endpoint size to support bigger sizes? Any help is greatly appreciated.

Thanks,
Tom

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  • Though the endpoint has greater size than 64 bytes, the USB spec limits the max packet size of interrupt endpoint to 64 bytes on full-speed.

    On the firmware, a report of greater size than 64 bytes is split into multiple packets. For example, a 200 bytes report is split into 4 packets,
    64 - 64 - 64 - 8
    Just the last packet is less than or equal to 64 bytes.
    Each packet is transferred in the interval (bInterval value) of the endpoint descriptor.

    On the PC side, the report is transferred with single read/write call, regardless of its size.

    If you have still interest in greater size report, we'll discuss on the implementation details.

    Tsuneo

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  • Though the endpoint has greater size than 64 bytes, the USB spec limits the max packet size of interrupt endpoint to 64 bytes on full-speed.

    On the firmware, a report of greater size than 64 bytes is split into multiple packets. For example, a 200 bytes report is split into 4 packets,
    64 - 64 - 64 - 8
    Just the last packet is less than or equal to 64 bytes.
    Each packet is transferred in the interval (bInterval value) of the endpoint descriptor.

    On the PC side, the report is transferred with single read/write call, regardless of its size.

    If you have still interest in greater size report, we'll discuss on the implementation details.

    Tsuneo

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