Re: [pyusb-users] "Other error' reply to set_configuration

[John C. <jo...@jc...>]

On Thu, 25 Feb 2016 13:31:26 +0800
Xiaofan Chen <xia...@gm...> wrote:

> I am not so sure if pyusb will allow you to reach the full potential.
> 
> In order to have better speed, increase the transfer size, use async I/O
> and then use an external HUB.
> 

Again, very useful. Thanks!

I rewrote the C program to see if it was faster than pyUSB, but
without hub, the speed is _exactly_ the same. I have been testing up
to 8192 bytes transfer size (I am limited with the device's memory).

Tomorrow, I will add a test function to check async transfer.
(It being tomorrow already, I did test using libusb in async mode,
but there was no difference at all. If anything, it was 0.5 - 1%
slower).

I checked, the hub is a single TT version (Genesys Logic Inc). It 
does wonders at smaller transfer sizes. At 512, speed goes from
128kB/s to 508kB/s - wow!

Cheers,
John