How to use GraphCreator with highpass filter

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stefan.erni
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How to use GraphCreator with highpass filter

Post by stefan.erni »

Hi Ben

The GraphCreator is working fine togheter with the Oled LCD_SSD1351 component.
For some signals a high pass filter would be very useful.This filter would also remove an offset.
For the graph I have a Signal with either 500Hz or 2kHz sampling rate. It's simple to add a point.
Creating the DSP functions is also easy.
Question: Do I need a buffer or can I only work with one variable ?
or how can I just insert the filter in a simple way?
Filter2.PNG
(3.39 KiB) Downloaded 1494 times
Filter1.PNG
(40.19 KiB) Downloaded 1494 times

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Benj
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Re: How to use GraphCreator with highpass filter

Post by Benj »

Hello,

You're on the right track. How about something like this?
FilterDemo.fcfx
(17.7 KiB) Downloaded 231 times

stefan.erni
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Re: How to use GraphCreator with highpass filter

Post by stefan.erni »

Hi Ben

The Highpass Filter is working nice. For a test I inserted a middle line (Baseline) in blue and the not filtered Signal in green.
So the green Signal goes out of range if there is a offset. The red stays in the middle.
The another picture is the result.


Green = not filtered
Red = filtered
Blue = Zero line (Baseline)
WP_20190227_09_59_17_Pro_ok_red1.jpg
WP_20190227_09_59_17_Pro_ok_red1.jpg (190.84 KiB) Viewed 3057 times
WP_20190227_10_24_02_Pro_red.jpg
WP_20190227_10_24_02_Pro_red.jpg (151.6 KiB) Viewed 3057 times

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