added WIP firmwares

pluck/README.md

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+# Pluck
+
+Pluck is a Karplus-Strong string plucking thing.  You pluck a string by providing a PITCH
+and then triggering the TRIGGER.  Pluck maintains up to 4 voices of strings being plucked at 
+one time.  No two plucks will sound exactly alike, nor will they have the same decay nor volume.
+
+SET GRAINS TO MOZZI MODE.  Sorry, no Grains mode.
+
+You will need to install the Mozzi Library.  You can do this from the Library Manager
+in your Arduino IDE.
+
+There are three options for plucking.  First, you can set the DECAY of the pluck.  Note that higher
+note plucks will decay much faster regardless, but you can stretch them out this way.  Second, you
+can set the GAIN (the volume).  Longer decays will sound increasingly metallic and when they pile 
+up you'll need to reduce the gain.  Third, you can set the ATONALITY of the pluck: how much
+it will sound like a string versus an atonal drum or crash sound.  
+ Basically more atonality rapidly adds more and more noise to the sound.  
+
+You can't have both ATONALITY and DECAY on the IN 2 knob and input: one is relegated to CV via IN 3.  
+By default ATONALITY is on IN 3 and DECAY gets the IN2 knob/input.  But if you'd like to swap that,
+just uncomment a #define in the code.
+
+Note that if you change the atonality, pitch, gain, or decay, it will not affect the currently plucked
+notes: it only affects later notes.  This trick helps the computational efficiency of the program and
+thus the quality of the note sound: but in fact changing any of these four elements in real time adds
+weird and undesirable artifacts in Mozzi, so you wouldn't want it anyway.
+
+
+## Tuning
+
+Unlike other Mozzi projects, Pluck has to compute the wave array size immediately in order to play it.  This means 
+it that has to make a snap judgment about the current pitch, and sometimes it's wrong because GRAINS / Mozzi
+are very sloppy and noisy in providing proper pitch information.  So occasionally it'll be off when you play it.
+I will try to work on it, but expect Pluck to not be exactly on pitch every time you do a pluck.  I can make it
+more accurate, but at the expense of much more latency (and Pluck has plenty of latency already).
+
+Also, you can adjust tuning, but note that Karplus-Strong is limited in its ability precisely match
+a given pitch.  High plucks will be far, far less pitch accurate than low plucks.  The lowest 
+pluck you can do is 64 Hz (roughly a C two octaves below middle C).
+
+
+
+## Adjusting Tuning and Tracking
+
+Grains's Inputs track 1.3V/octave, not 1V/octave: we'll need to scale them to track properly.  
+To do this, you can adjust the Pitch CV Scaling on Pot 1.  This GRAINS program is set up to play 
+the C three octaves below Middle C when it receives 0V.  You should be able to use Pot 1 to scale 
+the pitch such that high Cs play in tune as well.  Once you have things tracking well, you can 
+then use the Pitch Tune (Audio In) to tune 0V to some other note.  Note that as GRAINS resistors 
+warm up, the scaling will change and you will need to adjust the tracking again, at least until 
+they are fully warmed up.
+
+By default the note corresponding to 0V is C0, three octaves below middle C, that is MIDI note 24, 
+or 32.7 Hz.  You can customize the tuning for this Grains program but only UP.  This can be done 
+in two ways.  First, you can add pitch to the tuning with a CV value to Audio In.  Second, you 
+can transpose the pitch up by changing the TRANSPOSE\_OCTAVES and/or TRANSPOSE\_SEMITONES #defines 
+in the code to positive integers.  You can also change TRANSPOSE\_BITS: a "bit" is the minimum possible change Grains can do, equal to 1/17 of a semitone.
+
+
+## Grains Bug
+
+There is a bug in GRAINS that affects Pots (Dials) 1 and 2.  If you set the switch to "Man", 
+then the range of the Pot is correct.  But if you set the switch to "In 1" (or "In 2"), then 
+the range of the Dial is maximum (1.0 or 5V for our purposes) at about the 2 o'clock position 
+on the Dial.  Beyond that it stays at 1.0.
+
+## Configuration
+
+#### IN 1
+Pitch CV
+#### IN 2
+Decay (or Atonality) CV
+#### IN 3
+Atonality (or Decay)
+#### AUDIO IN (A)
+Pitch Tune
+#### AUDIO OUT
+Out
+#### DIGITAL OUT (D) 
+Trigger
+#### POT 1
+Pitch CV Scaling	[Set the switch to IN1]
+#### POT 2
+Decay (or Atonality)
+[If you're not using Decay/Atonality CV, set the switch to MAN]
+#### POT 3
+Gain
+