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Teensy DSP filter

  

Recently I noticed a thread on the group regarding a DSP filter designed
by Gareth Gi1MIC.? Although he primarily designed it to be fitted inside
an FT-817 he does say that it would operate perfectly as a stand alone
unit in a powered speaker.? I was very keen on this and (rather rashly
it seems) bought a Teensy to build one. The circuit is ridiculously
simple and I did not think that I would have any problems with it.?
HOWEVER, although he mentions an encoder control for setting the filter
centre frequency and some means of switching between filters, he gives
no details of how this should be done.? I have contacted Gareth to ask
for help but he seems uninterested and merely suggested that I learn
programming as it was all in the code.? At my advanced age learning to
programme is a daunting task (although I am trying).

Is there anyone on the group who could help me? 
What I want is simply a means of selecting the various filters (probably
with push-buttons or a rotary switch) and a means of fitting an encoder
to select the filter centre frequency.
The link to the project is :-


David G4LDT
 

H David...
i have been looking at this project and as soon as my bitx arrives, I will work on integrating it. I am a fairly proficient developer, so it shouldn¡¯t pose any problem.
ill keep you, and the group, posted.
/ Gerry
 

Take a look through "dspfilter.h" and "settings.h" they have pin settings for encoders
 

also try DLing to view his circuit diagram
 

The default behaviour for a 'generic' configuration, i.e. not installed in an FT817, is to pull pin0 low to advance through the filters.
The code will pull-up the pin, so all you need to do is attach it to ground through a pushbutton. Every time you press the button, it will switch to the next filter type.
In order to enable this behaviour, you will need to comment out the FT817 line in settings.h

#define FT817

so it looks like

// #define FT817

The wiring is as in this diagram (with the jack sockets replaced by direct connections to the uBitx audio chain):



HTH
Gerry

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