Playback file reproduction on cRIO

[zundap1970]

Hi all,

I'm looking for some example on how can reproduce a file (with two columns : time stamp and value) on cRIO.

The idea is reproduce the data recordered from the filed in the lab.

Someone can help me?

Thanks

[crossrulz]

What is the format of the file?  How accurate do you need the timing on the output to be?

[zundap1970]

Hi,

my sample time is 5msec and the file format is a *.txt file.

Thanks

[GerdW]

Hi zundap,

so you want to create the same kind of file with the same file format as has been done on your other laboratory computers?

Why don't you use the very same VI to do so?

(When the VI was created with "reusability" in mind that should be no problem!)

[zundap1970]

Sorry, there is a misunderstanding.

Let me explain better.

I recieve a file (*.txt format) with 2 or more column : time stamp (T=5msec) and value (e.g. volt value)

I need to reproduce the condition in lab so I use this file as data source to stimulate the equipment (target) in lab.

My cRIO project must read this file and generate the same signal (Volt) with the same occurancy (T=5mec) to stimulate the target.

[GerdW]

Hi zundap,

so you need to read the file on your cRIO.

Then use a loop to output the analog voltage at the right time…

What have you tried? Where are you stuck?

Do you have any specific questions?

Did you transfer the file to your cRIO already? Do you know it's a computer of its own - with all consequences?

How do you use your cRIO? ScanEngine? FPGA?

Which LabVIEW version?

[wiebe@CARYA · Accepted solution]

You'll need to parse the file, to get an array of timestamps and an array of values. Then, for each timestamp, probably subtract T0, to get relative times. Then, for each entry, set the voltage, and wait the next dT... Then fix details until it does exactly what you want....

Instead of parsing the entire file, you could read a line, 'execute' it (set output voltage and wait) and then read the next line. This will probably be friendlier on memory and real time behavior.