I built my digital data acquisition using stratix III dev brd and dsp builder. Now I need to output and save my captured data to any interface usb, sd card or even signaltap and I am guessing sd card implementation can be thevsimplest way so that it is standalone and I do not need a pc during measurement. USB implementation is more work and also means I need to develop user interface. alternatively I used signaltap but would not allow me to capture more than 16 seconds worth of data whereas my target is about 5 minutes continuously. Any suggestion to build interface for capturing my data properly would be highly appreciate it. Thx!