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Header size in high speed data logger

Thx,
What is the range of numbers written if I have 12-bit board and -10 to +10 Volt inputs?
George
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Message 11 of 13
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The range of an I16 is what you have already mentioned : -32768 to 32767. The most significant 4 bits are not used if you have a 12 bit DAQ.
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Message 12 of 13
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Thank you Dennis again,
Seems the solution for dummies is as following (assuming sampling of 4 channels):
Read the first 4 bytes of data file in editor like TextPad (can show HEX view!), convert it into an integer value, add 4. This is value to be set in the Origin 7.5 Import wizard of binary file.
Mark Big-Endian file.
Leave offset as 0, goto next page.
Create 1 Column of data as integer, changes Size to 2 bytes, make Count as 4 (columns of data). You should see proper structure of resulting data columns below. Change Designation of the 1st column as "Y" (right clicking its header), as it is not time. Finish importing (can save your way as Filter for future use).
It takes a while to go but the you see your data in Origin workshhet. Add a column before all imported data. Mark it as X, fill with values : i/(your sampling rate).
Make a plot, do whatever you need. Rescale dividing y-axis by 204.8 - results from +-2048 = 4096 values.
Seems not full range of 32k is used then? Correct me please if I am wrong.
Best wishes,
George


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Message 13 of 13
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