If you want to try a test create a workbook and put some values on Sheet1.
Right click on the Sheet tab at the bottom and select Sheet code (i think) VBA code for that sheet copy some code from here:
https://docs.microsoft.com/en-us/office/vba/api/excel.worksheet.change
So basically, if you change one of the values on sheet 1 it will create an event and run the code (note: once you have tried it manually you could then set up a DDE link), you could modify the code to do what you want for example append a CSV file with the data. Make sure your data on sheet 1 is not changing too often as events do take a lot of processing.
An example could be:
A value changes via DDE on sheet 1, the event triggers, In the code loop through the cells and compare it with a snapshot taken on the last event and compare the cells on sheet 1 with sheet 2, if one of the values has changed then write a line to the CSV file something like 02062013:43,"Operator has changed the setpoint to", xxxx The first bit is the date & time xxxx is the cell value.
Then copy all the cells from Sheet 1 to sheet 2 so you have a snapshot of the data ready for the next change event.
You will need to read up on Excel VBA there are plenty of examples on the net like the site above.
Things to think about.
Only read the data you need.
When an event is triggered you will need to check if the CSV file exists, if so append, if not create a new CSV file & first time write it.
Update the snapshot of the data so that you have some reference of which data has changed. you do not want to write all data to the CSV only the changed ones.
your filename could be Date& time for example 02052020.csv so each file is based on a day. so every day (or week for that matter) could be a new file.
This is just an example but I would populate an SQL database and store the information.
Right click on the Sheet tab at the bottom and select Sheet code (i think) VBA code for that sheet copy some code from here:
https://docs.microsoft.com/en-us/office/vba/api/excel.worksheet.change
So basically, if you change one of the values on sheet 1 it will create an event and run the code (note: once you have tried it manually you could then set up a DDE link), you could modify the code to do what you want for example append a CSV file with the data. Make sure your data on sheet 1 is not changing too often as events do take a lot of processing.
An example could be:
A value changes via DDE on sheet 1, the event triggers, In the code loop through the cells and compare it with a snapshot taken on the last event and compare the cells on sheet 1 with sheet 2, if one of the values has changed then write a line to the CSV file something like 02062013:43,"Operator has changed the setpoint to", xxxx The first bit is the date & time xxxx is the cell value.
Then copy all the cells from Sheet 1 to sheet 2 so you have a snapshot of the data ready for the next change event.
You will need to read up on Excel VBA there are plenty of examples on the net like the site above.
Things to think about.
Only read the data you need.
When an event is triggered you will need to check if the CSV file exists, if so append, if not create a new CSV file & first time write it.
Update the snapshot of the data so that you have some reference of which data has changed. you do not want to write all data to the CSV only the changed ones.
your filename could be Date& time for example 02052020.csv so each file is based on a day. so every day (or week for that matter) could be a new file.
This is just an example but I would populate an SQL database and store the information.
