Hi all,
FWIW here is the format I use for my Windows GPIB app and why:
As mentioned above, efficiency is key. Keep it simple.
INDEX, DEVICE NAME, DATE_TIME, VALUE, TEMPERATURE, HUMIDITY
1,3458A,2020-11-13_16:25:29,1.000002084,26.75,37.25
2,34461A,2020-11-13_16:25:29,1.00001,26.75,37.25
3,3458A,2020-11-13_16:25:30,1.000001982,26.73,37.26
4,34461A,2020-11-13_16:25:30,1.00001,26.73,37.26
5,3458A,2020-11-13_16:25:31,1.000002102,26.72,37.26
6,34461A,2020-11-13_16:25:31,1.00001,26.72,37.26
7,3458A,2020-11-13_16:25:32,1.000002236,26.73,37.25
8,34461A,2020-11-13_16:25:32,1.00001,26.73,37.25
9,3458A,2020-11-13_16:25:33,1.000001864,26.72,37.29
10,34461A,2020-11-13_16:25:33,1.000009,26.72,37.29
11,3458A,2020-11-13_16:25:34,1.000002005,26.73,37.26
12,34461A,2020-11-13_16:25:34,1.00001,26.73,37.26
13,3458A,2020-11-13_16:25:35,1.00000182,26.71,37.24
14,34461A,2020-11-13_16:25:35,1.000009,26.71,37.24
15,3458A,2020-11-13_16:25:36,1.000001369,26.75,37.33
16,34461A,2020-11-13_16:25:36,1.000009,26.75,37.33
17,3458A,2020-11-13_16:25:37,1.000002081,26.73,37.34
18,34461A,2020-11-13_16:25:37,1.000009,26.73,37.34
19,3458A,2020-11-13_16:25:38,1.000001753,26.72,37.42
20,34461A,2020-11-13_16:25:38,1.000009,26.72,37.42
21,3458A,2020-11-13_16:25:39,1.000001894,26.71,37.42
My app can log the data from two GPIB devices at the same time. The individual GPIB processes run in their own threads.
The logging to CSV etc is outwith that. The GPIB comms as a result is extremely reliable.....even on Windows.
The CSV file has the option to comma delimit or semi-colon delimit. The reason for that is because some Euro countries use the comma as a D.P. and therefore would mess up the CSV. The user can select accordingly.
When logging from two GPIB devices at the same time there is a common sample rate, user settable from below 0.5sec right up, hence the time stamp down to the second (1 sec and above for offline graph/plotting).
The INDEX doesn't do much, it's just handy to have, say when manually reviewing the file.
Since the sample rate is common then the two devices alternate in the file as you can see.
When each sample is taken the temperature & humidity is taken at the same time for graph plot overlay.
No calculated perameters are recorded in the file, i.e. graph plot overlay calculates PPM, PPM/DegC tempco stuff offline.
The graph plot overlay software allows the user to select either or both devices in a dual log CSV for display/analysis. The device name in the CSV is key to this, also theoretically, if the sample rate was to change half-way through for example then the offline graph/plot software can handle this and plot accordingly. Not sure I have tried this with mine but it should be okay as the plotting goes by the time stamp. There is no recording of the actual sample rate directly in the CSV.
Hope that helps,
Ian.