07-11-2006 04:46 AM
07-17-2006 10:51 AM
07-18-2006 03:35 AM
09-26-2007 03:44 AM
Hi, I just started evaluating the net2272 which I would like to use as a "low performance" DAQ interface (a few 100 MBit/s).
Did you finnaly solve all the problems you described, concerning the NI-VISA driver development for the USB host, if yes does
it run under Windows XP ?
Did you wirte some initialization procedure on the Local Bus side (for a CPU), if yes could you let me have it just as an additional
source of information ?
12-22-2017 04:21 AM
it seems you were able to solve issue of unoptimized data in your visa buffer. mine is also getting slow. please do tell me how you calculated speed of your data received in labview
hello Norbert,no I am not using USB 1.1 - the PLX is a High-Speed USB device and its connected in this mode.besides - the packet size is already the maximum the USB standard allows in this transfer mode .but I have located the problem in my firmware and sram read outs. because of a "slow" risc processor with only 50MHz and some unoptimized loadings into the usb buffers I just reacted to slow for IN tokens of the host controller.the actual speed I've reached is about 35MBit/s - that suits my requirements well.summary: VISA read is as fast as your code on any attached device. But now I just have another problem with using interrupt and bulk transfers on the same visa resource. It seems as I have to close the session every time I want to use another transfer type. But a VISA close needs a lot of time...I will see how to handle that problem.thanks so farmartin (gmb)