Hi. I’d like to use pipes in linux to stream in the result of filtering ADC input, but I wanted to start just by testing it out with the pipetest sample. There doesn’t seem to be a gui anywhere in the Frontpanel distribution. There’s a pipetest .exe file, but no .xfp files. I see in the release notes that Frontpanel 1.2.0 added linux makefiles for pipetest and counters, but they don’t seem to be in any of the packages that I downloaded. I apologize if I’m missing something obvious, but I just can’t seem to find the relevant files. thanks.
Yes, there’s presently no support for pipes within the XML profiles for FrontPanel. If you have suggestions for components that would be generic enough to be useful, please let us know.
Piping a file in or out would be relatively simple – would this be a useful feature? What settings would be appropriate? -length of transfer? -pre-transfer trigger?
I should also mention that the best “useful” sample for pipes is the DES sample in the online tutorial. It uses wires/triggers/pipes in a manner that actually does something.
Also, could you please tell me your Linux configuration and experience with the FrontPanel software/API? Different distributions seem to have problems with the libusb package that we use for the USB communication and I’m trying to get an idea of which ones work and don’t work without having to maintain 50 different Linux boxes!
thanks for getting back to me. I’ll try sorting through the DES example. I’m not entirely sure if pipes are what I need or not- I have an 8-bit 8-channel muxed ADC connected to 8 lines of the XEM and I simply want to log the data as it comes in and simultaneously plot it. I think that would be a great example, if it makes sense. If you extended the matlab example in the documentation just a little bit further to include display of data getting piped in, I imagine many people would find it useful.
My current setup is dual-boot windows xp/gentoo linux 2.6.11-r6 with hyperthreading/SMP enabled on 3.6Ghz P4 w/ 2Gb RAM (Dell dimension XPS). Since your update which fixed the problem with fast computers, USB works perfectly, configuration works every time. I haven’t tried pipes yet so I can’t tell you performance there yet. The version of libusb installed here is 0.1.10a.
On windows I got the XEM to work with Xilinx system generator jtag cosim in matlab and with modelsim hardware cosim pretty easily. If it’s of any interest, I can send along more about that.
Thanks for the feedback on Linux – very much appreciated.
As for the cosim setups, I’d be more than happy to post it to our 3rd-party contributions if you have anything put together. I’m sure others would appreciate the work!
Regarding the 8-bit ADC – how fast is the data coming through? You could either attach all 8 ADC values to WireOuts and pull them in that way. Alternatively, PipeOuts would work fine.
Pipes are considerably faster but you’ll need some mechanism to throttle the data. Either a trigger to tell the device to sample or something. You could even use every 8th pipe read to trigger another sampling. This would avoid the overhead of a trigger.