Multifunction DAQ
Streaming inputs to file and to output
Hi Lahan,
I'm not seally sure how to interpret the signal you have posted here. There might be something with your connection, but even with reactive load on your source, this signal looks quite weird if it should be sine 
If you look for ways how to pass Analog Input to Analog Output, then I would ask what do you need it for?
Because, If you acquire samples by AI at specified sample rate and pass those data to output (possibly with some processing), then you can do it just with some reasonable delay between acquisition and generation. Moreover, you need to turn off regeneration mode to assure that each sample will be generated just once. You also need to assure that you have all the time some data in generation buffer, so you can generate while you are acquiring and making processing. But there has to be some additional logic which handles situation that you will not overflow nor underflow the output buffer over longer period of time. The buffer size, and related delay between signal on input and output will depend on how much processig you need to do between them.
If you just need to acquire some signals and generate other, then you just simply create 2 different tasks - AI and AO, and run them separately.
In some cases what I just described might not be the most appropriate solution, and maybe you would need FPGA. In other application, where you don't need solution, just connect cable from AI (or better said from your signal generator) to place where you need to have the signal, and don't pass it trough AO of DAQ.
Therefore I believe that for people on this forum be able to advise you better, would be good idea to give us some more bacground on what you try to accomplish and why.
Regards,
Stefo
Lahan,
if you need to do simultaneous sampling, processing and generation with as little delay as possible, you should likely go for FPGA platform. Here we are talking about us delays between AI and AO. I can say that ethernet solution is not the most suitable, because you need to count with bigger delays between AI and AO as you would get with PCI. If you need to have distributed IO, you could go for CompactRIO solution.
If you are playing with DAQ platform now, and you struggle how to communicate data between loops, I think the best is to use QUEUE. You should be able to find few examples on how to communicate between multiple loops with queue.
regards,
stefo
Lahan,
if form factor is the only concern, then I have to say that cDAQ and cRIO are practically the same size. cRIO needs controller - but it migh be integrated into chassis (in 8 slot chassis). I suggest you to contact your sales representative and speak with him exactly about your application.
Queue works like FIFO. You can keep putting data into queue, and when you are reading, you are reading all elements which you wrote and in the same order as they were written. When you want to see examples about queue, open example finder (help -> find examples), and search for queue. I believe that from example called Queue Basics.VI it should be clear.
Functional global variables will work with queues, just you need to separate reading and writing. Reading from queue might wait for element even indefinitely long (depends on how it is configured), which could block writer if there were no elements in queue.
Aha. In fact the device you are refering to is not cDAQ, but ENET carrier.
i'm glad that it works for you already.
