Forums

EZUSB FX2LP communication speed

Started by Unknown November 9, 2006
Hi out there,

I am trying to build a device that reads data for a error measurements
as fast as possible. I want to read data from the FX2s GPIF and send it
to a host PC. Now I have my first test hardware an I am able to
transfer data with app. 2,5 MB/s using endpoint 6 with 512 Byte packet
size and double buffering. I read data with an external clock of 40
MHz. Data packets are sent by the internal logic automatically using
the bytecount register. Is there any possibility to speed up the
device? What about external memory buffers? I think that reading data
to the fifos will be much faster than sending data to the PC. So what
do I have to do to speed up my system and transfer data with higher
speeds? 10MB/s would be very nice ;-)

Thank you for your answers

Christian

I was told in this forum that you must have packets ready as fast as the 
host wants them. If you there is a miss, then the host waits another cycle 
(1ms for USB1.1 and 125microSecs for USB2.

I was only able to get around 3MB Sec from my device because of the nature 
of the hardware I am using GPIF to communicate with.


<mail@cgrobi.de> wrote in message 
news:1163069393.591557.54890@m73g2000cwd.googlegroups.com...
> Hi out there, > > I am trying to build a device that reads data for a error measurements > as fast as possible. I want to read data from the FX2s GPIF and send it > to a host PC. Now I have my first test hardware an I am able to > transfer data with app. 2,5 MB/s using endpoint 6 with 512 Byte packet > size and double buffering. I read data with an external clock of 40 > MHz. Data packets are sent by the internal logic automatically using > the bytecount register. Is there any possibility to speed up the > device? What about external memory buffers? I think that reading data > to the fifos will be much faster than sending data to the PC. So what > do I have to do to speed up my system and transfer data with higher > speeds? 10MB/s would be very nice ;-) > > Thank you for your answers > > Christian >
Hello,

> 2,5 MB/s using endpoint 6 with 512 Byte packet > size and double buffering. I read data with an external clock of 40 > MHz. Data packets are sent by the internal logic automatically using > the bytecount register. Is there any possibility to speed up the > device?
perhaps have a look on the following page: http://oscar.dcarr.org/ssrp/index.php Regards, Martin