A2C-SG2-M12
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11.2
Using the A2C-Sensor Utility
The FIR parameters and coefficients can easily be changed using the graphical editor. To import coefficients, save them as a .coeff
filetype. Each line in the file should have one single coefficient, with the first line being Coeff 0.
-0.0018225230
-0.0015879294
…
+0.0080754303
+0.0085302217
-0.0000000000
Press “Send coefficients to sensor” to update the A2C-SG2 coefficients. In the filter setup section set the number of taps and click
the checkbox to enable the FIR filter. Press the “Send setup parameters to sensor”. For the A2C-SG2 to load the filter values at
startup they must be saved first. Press the “Save Filter 1” and “Save Filter 2” to save the values to the memory, respectively for filter
1 & 2.
11.3
Using MATLAB
In MATLAB a FIR filter can be designed with the fir1 function:
h = fir1(28, 6/24);
The first argument is the filter order which must be one less than the desired length. So for this example the number of taps is 29, but
we input 28. The second argument is the cutoff frequency in the range of 0 (DC) to 1.0 (Nyquist).
The A2C-SG FIR filter function requires the coefficients to be in time reversed order and this can be done using the ca