A/D Data Conversion - Agilent Technologies U2300A Series User Manual

A/D data conversion

#800000200
Data length indicator, The
next 8 bytes (0000 0200)
specifying the actual data
length only, not actual data.
Data length (200 bytes long)
U2300A Series USB DAQ User's Guide
A/D data conversion converts analog voltage into digital
information. The following section illustrates the format of
acquired raw data for the A/D conversion.
Below is the illustrated example of the acquired raw data
scan list for CH 101, CH 102, and CH 103.
<byte> <byte> <byte>
1st data 1st data 1st data
LSB MSB LSB
CH 101
16-bit Data Format
LSB
DDDD DDDD
12-bit Data Format
LSB
DDDD XXXX
D - Data bits
X - Unused bits
Raw data conversion
To convert the data into an actual float number, we need
the voltage range and polarity information. Below are the
calculations on the raw data conversion for both bipolar and
unipolar.
To perform a sample calculation of the conversion, take
the U2356A as an example. The resolution of U2356A is
16 bits and the range is taken as 10 V. The Int16b value
calculated using conversion algorithm is 12768.
<byte> <byte>
1st data 1st data
MSB LSB
CH 102 CH 103
MSB
DDDD DDDD
MSB
DDDD DDDD
Features and Functions
<byte> <byte> <byte> ...
1st data 2nd data 2nd data
MSB LSB MSB
CH 101
3
...
...
47