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Date: Sun, 21 Sep 2014 19:28:39 +0200
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Subject: Re: Running Technisat DVB-S2 on ARM-NAS
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> If I didn't remember wrong, that means allocated buffers are 8 * 32 *
> 2048 = 524288 bytes. It sounds rather big for my taste. Probably even
> wrong. IIRC USB2.0 frames are 1024 and there could be 1-3 frames. You
> could use lsusb with all verbosity levels to see if it is
> 1024/2048/3072. And set value according to that info.

lsusb tells:
    Interface Descriptor:
      Endpoint Descriptor:
        wMaxPacketSize     0x0200  1x 512 bytes
      Endpoint Descriptor:
        wMaxPacketSize     0x0200  1x 512 bytes
      Endpoint Descriptor:
        wMaxPacketSize     0x0200  1x 512 bytes
    Interface Descriptor:
      Endpoint Descriptor:
        wMaxPacketSize     0x0c00  2x 1024 bytes
      Endpoint Descriptor:
        wMaxPacketSize     0x0200  1x 512 bytes
      Endpoint Descriptor:
        wMaxPacketSize     0x0200  1x 512 bytes


But I haven't got any clue about the meaning.
Ask me a question about any bit in the tcp/ip packages, but don't ask me
about USB ;)
Where can I get technical details that are, well... readable without
studing for weeks?

btw, it's attached to a FT1009 USB3.0 SuperSpeed chip.

> So I would recommend
> .count = 6,
> .framesperurb = 8,
> .framesize = 1024,
> 
> Use some testing with error and trial to find out smallest working
> buffers, then add some 20% extra for that.

I set to 8x8x2048 (because max package size is 2x1024)
but w_scan doesn't find any transponder.

What should happen if buffers are too small?

Tommorrow I'll swap the sat cable just to make sure this isn't the cause.

thanks,

Jan