FPGA Central

In January there was a discussion about the Spartan-3 LC kit from Memec.
(http://www.memec.com/Memec/iplanet/l...artan3LC_3.pdf)
I'm wondering if anyone has purchased the kit and has any comments?

In particular I’m interested in the USB 2.0 Interface. We are
speculating that it uses a USB2.0 High Speed transceiver and hence
requires a USB2.0 SIE core to be implemented in the Spartan. Is this a
correct assumption? Does anyone know what percentage of the device does
the USB 2.0 High Speed SIE core use?

We are weighting it up with other boards which has an onboard Cypress
EZ-USB FX2 2.0 Full Speed USB Controller and hence once
configured/enumerated we can just clock the data into this device and it
can deal with in leaving the Spartan III for other things.

"Dave" <postmaster@localhost> wrote in message
news:[email protected]...
>
> In January there was a discussion about the Spartan-3 LC kit from Memec.
> (http://www.memec.com/Memec/iplanet/l...artan3LC_3.pdf)
> I'm wondering if anyone has purchased the kit and has any comments?
>
> In particular I’m interested in the USB 2.0 Interface. We are

S3LC uses Silabs serial to usb converter chip CP2101
www.silabs.com/products/pdf/CP2101_Short.pdf

Antti
http://xilinx.openchip.org

Antti Lukats wrote:
> "Dave" <postmaster@localhost> wrote in message
> news:[email protected]...
>
>>In January there was a discussion about the Spartan-3 LC kit from Memec.
>>(http://www.memec.com/Memec/iplanet/l...artan3LC_3.pdf)
>>I'm wondering if anyone has purchased the kit and has any comments?
>>
>>In particular I’m interested in the USB 2.0 Interface. We are
>
>
> S3LC uses Silabs serial to usb converter chip CP2101
> www.silabs.com/products/pdf/CP2101_Short.pdf

Thanks for the Info. While I guess the data sheet is technically
correct, I do believe it is a little misleading.

The CP2101 is USB 2.0 complaint, but only runs a full speed (12Mbps) and
worst still the exposed asynchronous interface to the FPGA has a maximum
921.6 kbps. You would have expected the datasheet to at least mention it
uses a serial to USB bridge.

In my opinion, if they wanted to use a simple USB to serial bridge type
interface, they would have been better using a FTDI FT245BM which has a
1 byte wide Parallel FIFO bi-directional port to USB Virtual COM driver.
It has a 1M Byte/sec transfer rate (8Mbits/sec).