Thank you Annette, your answer allows me to understand some details about PCI-5112 board.
I need to acquire continuously data at 2 Msample/sec for 10 minutes at least, without loss, and signal level can slowly change during the acquisition (es. a sinusoidal amplitude increasing from 0.5 to 2 V into 10 minutes).
It’s important to adjust the vertical setting due to use all the dynamic range.
I’ve used “niscope Fetch&Save Forever.vi”, performing a single channel continuous acquisition with 8-bit fetching data (“1 channel acquiring – 1 channel fetching” example).
Fetch operation is inside the loop, while all the configuration ones are outside, so if I want to change a configuration parameter, I have to exit from the f
etching loop, stop the acquisition (with “niscope abort.vi”), set the new parameters and finally restart the acquisition, with a necessary loss of data.
I thought a second way: “2 channel acquiring – 1 channel fetching”.
If I have well understood, I could acquire the same signal from both the channels, configured with different vertical settings (es. +/-1V and +/-2.5V respectively), so I could fetch data from the better vertical range channel only.
In this mode I perform an effective vertical setting (but in 2 steps only) during the continuous acquisition without data loss.
First question:
Is it right? Is the last example (2 ch. Acq. – 1 ch. Fetch) more expensive with respect to the first (1 ch. Acq. – 1 ch. Fetch) in terms of PC and/or OS resources?
I have inserted the PCI-5112 board in a Pentium III, 128 Mb RAM, with Windows ME OS.
Second question:
Sometimes, during the fetching operation, the board stops the acquisition (I see
noise only), and it’s necessary to make the shutdown of PC, before to see the signal again!
Is it necessary a reset (with "niscope Reset.vi")? Is a Windows ME bug? Is a board failure?
Thank you in advance.
