Datalogging using Waveform for long hours

[naganathas]

Hi all,

 Im logging the data using the waveform. The chart length size is given as 1024. I need to log the data for long hours (5 to 10 hours). How much i have to set in the chart length ? how it is calculated ? Is it the right way for extended period of data logging ?

Naganatha Subramanian

[nitad54448]

hi

you can change the history lentgh from 1024 to 36000... i guess it will require a lot of memory though

N

[Ben]

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@naganathas wrote:

Hi all,

 Im logging the data using the waveform. The chart length size is given as 1024. I need to log the data for long hours (5 to 10 hours). How much i have to set in the chart length ? how it is calculated ? Is it the right way for extended period of data logging ?

Naganatha Subramanian

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I'll assume you are asking about the "Wavefrom datatype" when used with charts.

The history length is the "number of waveforms" and not the number of points. If you present an hours worth of data once every hour, it will display 1000 hours (in thoery, never tried it with those numbers and high sample rates will tax memory).

If your app spec has a hard and fast req that it drop suff older then the code will have to regularly examine the time of what is in the history and explicitly remove the old stuff ( read history, toss old, redefine history).

Ben

[Coq_Rouge]

Post your current code. If you want to log data for a periode. The best thing is to write data in chunkes to a file. What is your sample speed?