OPENCORES.ORG

Hi Dalton,

hello,
excuse me, please.
i am trying to implement the USB1.1-core, but it just dont want to work..
the FPGA replys corrcectly with the device-descriptor to the PC-question..
but PC asks for more bytes, and dont accepts it :-(
did you have to make some changes to the orginial core, to get it working?
do you have a protokoll of the handshake between your devive and the PC?
could you please tell me the device-descriptor you used?

i would be very pleased for any informations or hints.
thank you very much
best regards

Suheel Georges

Zitat von Rahul Kumar <kumarah@g...>:

> Hi Dalton,
>
> I have successfully implemented USB 1.1 in FPGA and I discovered the
> same thing. My endpoint 1 OUT FIFO was 8 bytes deep. I discovered that
> if I allowed the fifo_full signal to go high, the USB core didn't like
> it and the windows application crashed. So I had to change the design
> to make sure I read each byte as it is written.
>
> Rahul
>
>
> On Mon, 22 Nov 2004 17:14:32 -0500, Dalton Marris <dmarris@c...>
> wrote:
> > I have created a new test for the USB 1.1 OpenCores testbench by
> > modifying the original "out0" task.  I commented out the "fork" and
> > "join" lines (558 and 621) so that all of the data is written to the
> > fifo before anything is read out of it.  With a fifo depth of 256, I
> > would expect the test to pass until the total number of bytes written to
> > the fifo is more than 256.  With that said, when no_pack = 3 (actually 4
> > packets) and pl_size = 64, a total of 4 x 64 = 256 bytes will be written
> > to the fifo.  This will fill the fifo, but just to it's maximum depth.
> > When this scenario occurs, the testbench fails, and I get the following
> > error message:
> >
> > ERROR: ACK mismatch. Expected: d2, Got: 5a (2748140.0 ns)
> >
> > I have verified that I am indeed getting a NACK back.  Shouldn't I be
> > able to fill the fifo, as long as I don't try to overfill it, without
> > generating a NACK?
> >
> > Regards,
> > Dalton
> >
> > _______________________________________________
> > http://www.opencores.org/mailman/listinfo/usb
> >
>
>
> --
> Regards,
>
> Rahul Kumar
> _______________________________________________
> http://www.opencores.org/mailman/listinfo/usb
>