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# System prepended metadata

title: OTTO DESIGN SCRATCHPAD

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# OTTO DESIGN SCRATCHPAD


## 


## LFO / MODULATION / SYNTH CONTROL

Synth button. Possibly several screens

Envelope button. Screens (possibly):
- Volume envelope
- Modulation envelope
- LFO xN 
- reusable elements (widgets)
- Screen change animation (dots?)
- pitch lfo target


## FM:
- Move out envelopes to env. screens
- Encoders:
    - Global: Algorithm
    - Operator: Ratio + Detune (shift)
    - Operator: Volume + Global: All modulators volume/FM amount (shift)
    - Global/Operator: Feedback
- Envelopes:
    - 4 ADSRs, all visible. Not-selected envelopes are 'minimized' to a line.
    - Shift changes a parameter for all envelopes. Perhaps split into only modulators or only carriers.

### Graphics
Very industrial-looking
- Algorithm is a dial or a line of numbers like an old clock where each digit moves independently.
- Ratio: animate the numerator and denominator separately, floats cast to ints, quad in-out.
    - Detune is a smaller line with a center marking
- Volume: Bar that fills up. Perhaps with squiggly effect? When shift is held, the fill fades away, leaving vaguely coloured lines for the modulators that you are controlling together.
- Feedback: Some thing that lights up and gets more squiggly

## I2C Protocol:
17 bytes? 1 Command byte, 16 databytes
Commands/Events:
 - midi: Data bytes are normal 3 midi data bytes.
 - set_led: 1 byte for LED ID, 3 bytes for colors
 - clear_all_leds: No data, used on boot, shutdown
 - Keypress/Keyrelease/encoderEvent: 
 - power_off: no data
 - battery_level: to be used with battery add-on
 - button_state (TODO)

- 1st byte: Command type (Button state, LED events, encoderturn, HW MIDI, USB MIDI, Power info)
    - Optionally subdivided into query/response

## LEDs
- Disabled keys are off
- Synth mode: 
    - All blue
    - keyboard leds light up midi post midi fx
- Drum mode: 
    - All green
    - Accent colors on black keys to show active channel
    - Colors on white keys to show current and triggered steps

 

