=sum of current row without using row number

[Mad Professor]

Good day all.

I don't often use excel, and when I do it's for very basic things.

But I am stuck with doing excel formulas.

I am building a Arduino based datalogger, and I am trying to export the RAW ADC data into microsoft excel, every 5sec.
This is so I can Graph the voltage of the ADC pins of the Arduino.

If I was to manualy type the needed sum into excel it works fine:
=SUM(5.08 / 1024 * B2)

And gives me the real time voltage of the arduino adc pin in question.

But as the Arduino is generating all the data, and filling in all the excel cells, I can not use the above sum.

I need to have the Arduino export data into excel looking more like this:

=SUM(5.08 / 1024 * B"CurrentRow")

Can someone please advice if this is possible, and if so how I go about doing it.

Thanks for your time.

Best Regards.

[Tony Valko]

Does that mean a new row of data is added every cycle and you need the formula to reference the LAST (bottom-most) value from column B?

If so, try this:

=5.08/1024*LOOKUP(1E100,B:B)

[Mad Professor]

Yes, There is a new row of data added every 5sec.

But I only need to do a sum on one cell of the new row, not the whole column.

If I was to manual type each some it would be.
Cell D2 would be: =SUM(5.08 / 1024 * B2)
Cell D3 would be: =SUM(5.08 / 1024 * B3)
Cell D4 would be: =SUM(5.08 / 1024 * B4)
Cell D5 would be: =SUM(5.08 / 1024 * B5)

and so on.

Here is a quick screen shot, with my manualy adding the data.
excel adc1.jpg

I hope this makes sence.

Best Regards.

[Tony Valko]

Ok, then all you need to do is enter the formula in cell D2 then drag copy it down as far as needed.

You don't need the SUM function.

Entered in D2:

=IF(B2="","",5.08/1024*B2)

Then, just drag copy down column D as far as you need to.

The formula cells will remain blank until data is added to the cells in column B.