Mad Synth #3 How to read your keyboard with a microcontroller?

Addictive Synthesis episode three

In this rushed fourth installment of the synth series I'll try to show you how to read what
keys are being pressed in a musical keyboard (using only a scavenged keybed). Sorry for the
long wait and low energy but things will finally improve next month. See you then :)

DDS: en.wikipedia.org/wiki/Direct_digital_synthesis
Desmos: desmos.com/calculator
Harmonics wiki: en.wikipedia.org/wiki/Harmonic
keyboard how-to: instructables.com/Figuring-out-a-Key-Matrix-Scan-Matrix/
keyboard schem: openmusiclabs.com/learning/digital/input-matrix-scanning/index.html

Soundtrack: White Bat Audio - Arcadia

00:00 Introduction of the task ahead
01:04 The many topologies to achieve it
04:37 My circuit design
06:50 Load Resistance
10:00 Choosing the right OpAmp
11:11 My mistake while coding
13:57 ESP32 GPIO's and registers
14:35 What lies ahead
15:57 input FSM
16:44 Ending?
17:46 Removed features and next steps