Multifunction DAQ
nifslk.dll BSOD
cfabe and I are good friends from high school, so I'll take this one
First off, I'm going to assume you have LabVIEW 8.0 since you were using DAQmx 8.0 to start with. Correct me if I'm wrong. Also note that LabVIEW 8.2 is out and you may be able to use that. Also, LabVIEW 8.0.1 is out which provides fixes, but note that you should install this at the end of the day because it takes a few hours to do a mass compile. These probably have nothing to do with your problem but I'm just letting you know they're out there.
Anyway, a few structural problems with your code:
- You are using a while loop with no execution timing and polling a boolean to get it kicked off. This will suck too much CPU and may result in things being run multiple times. Use an event structure
- You need to take a look at the full structure of DAQmx programs, see the Example Finder at Help >> Find Examples... >> Hardware Input and Output >> DAQmx >> Analog Measurements >> Voltage >> Acq & Graph Voltage-Int Clk.vi. See how the Task gets created, started, read, and destroyed? We need that timing.
- Sequence structures are generally frowned upon when not absolutely needed. You are duplicating too much code. For this, I propose a For Loop to pop out a couple of 2D arrays of data that we can then parse back out (or just display in a big indicator).
- Since you are using the same resource 5 times, we don't need to close and re-open it a bunch -- that's wasteful. Let's loop around the same resource and just do 5 different reads on it. This will also allow our error lines to get shifted back in with shift registers, so that the DAQmx Read knows not to goof around with the resource if there's already an error on the line.
Let me know if this program causes you problems. I'm NOT a DAQ go-to but I know it enough...
In the meantime, everyone else can congratulate cfabe on his recent engagement!
See ya!
berto
edit: I'm a moron and forgot to attache the VI i made!
First off, I'm going to assume you have LabVIEW 8.0 since you were using DAQmx 8.0 to start with. Correct me if I'm wrong. Also note that LabVIEW 8.2 is out and you may be able to use that. Also, LabVIEW 8.0.1 is out which provides fixes, but note that you should install this at the end of the day because it takes a few hours to do a mass compile. These probably have nothing to do with your problem but I'm just letting you know they're out there.
Anyway, a few structural problems with your code:
- You are using a while loop with no execution timing and polling a boolean to get it kicked off. This will suck too much CPU and may result in things being run multiple times. Use an event structure
- You need to take a look at the full structure of DAQmx programs, see the Example Finder at Help >> Find Examples... >> Hardware Input and Output >> DAQmx >> Analog Measurements >> Voltage >> Acq & Graph Voltage-Int Clk.vi. See how the Task gets created, started, read, and destroyed? We need that timing.
- Sequence structures are generally frowned upon when not absolutely needed. You are duplicating too much code. For this, I propose a For Loop to pop out a couple of 2D arrays of data that we can then parse back out (or just display in a big indicator).
- Since you are using the same resource 5 times, we don't need to close and re-open it a bunch -- that's wasteful. Let's loop around the same resource and just do 5 different reads on it. This will also allow our error lines to get shifted back in with shift registers, so that the DAQmx Read knows not to goof around with the resource if there's already an error on the line.
Let me know if this program causes you problems. I'm NOT a DAQ go-to but I know it enough...
In the meantime, everyone else can congratulate cfabe on his recent engagement!
See ya!
berto
edit: I'm a moron and forgot to attache the VI i made!
Message Edited by Berto on 09-25-2006 02:39 PM
