On Sat, Sep 10, 2011 at 3:16 AM, Joerg Wunsch <libftdi@xxxxxxxxxxxxxxxxx> wrote:
> Xiaofan Chen <xiaofanc@xxxxxxxxx> wrote:
>>> B.t.w.: How common are Full-Speed hubs. Is debugging worth the effort?
>>> And do you really bitbang? Why not MPSSE?
>
>> I do not think it is that common now. It is good to be used a debugging
>> tool. So I think this is not a high priority fix.
>
> For me, I do have a good number of fullspeed hubs around. My only
> highspeed hub is used whenever I need to plugin a mass storage device,
> but everything else (in particular, all that microcontroller stuff)
> runs on fullspeed hubs.
>
> My entire point is: if a FT232H device on a fullspeed hub runs at
> *much* lower speed than a FT2232D one *on the same hub*, something
> must be fishy. The expected behaviour would be that it achieves
> approximately the same speed.
This is a good point. The code will probably need to detect the
current speed (which is only added to libusb-1.0 git recently)
http://git.libusb.org/?p=libusb-stuge.git;a=summary;js=1
or current max packet size (512B in high speed mode, 64B
in full speed mode).
> And yes, with "bitbanging", I was just referring to the net result on
> the AVR microcontroller that is being programmed; all this is done
> through the MPSSE, of course.
>
--
Xiaofan
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