On Wed, 12 Feb 2003, [iso-8859-1] Aurélien GODIN wrote: >Hello, > >I have some trouble using the javax.usb package. I succeed in lauching the Usb >services, finding the devices and opening the corresponding pipes. If these devices >use interrupt transfer mode, everything's ok. >But I don't succeed in retrieving data when the device uses isochronous transfers. >Can somebody help and explain me what is the differences with the other modes and how >to collect the data ? (a few lines of code would be much appreciated...). >The device which is connected is a Labtec Webcam (352x288 images) : I have noticed >that two pipes are open, one functioning in interrupt mode (what is its use ?) and >the second one using isochronous mode but I have absolutely no idea how to handle >them !
The pipes should act in similar ways, you provide a buffer and it's either sent to the device (if the pipe direction is out, or host-to-device) or the device sends data to fill up the buffer (if the direction is in, or device-to-host). Essentially, you should be able to open the pipe(s), and submit one or more buffers to them (either byte[]s or UsbIrps, or List(s) of UsbIrps). If you're sending data to the device, it will get sent (if there are no errors); if you're getting data from the device, it will retrieve it from the device and fill up your buffers (assuming no errors). Roger or Boris may be able to help you with ISO transfers, but I think for simple communication (without caring about performance) you should be able to talk to ISO the same as interrupt... Note that there is a bug in the Linux JNI ISO section for the 0.10.0 release; get the code from CVS. >PS : Maybe this mailing list doesn't aim to answer such questions but I didn't find >any FAQ section. So, sorry if that was not the appropriate way to submit my issues... Yes we do need a FAQ and example code...sorry, for the moment there's none. -- Dan Streetman [EMAIL PROTECTED] --------------------- 186,272 miles per second: It isn't just a good idea, it's the law! ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ javax-usb-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/javax-usb-devel
