[sk] Korg Volca Sync Out + Arduino

Korg Volca synthesizers have two 3.5 mm jacks to sync with other musical instruments. One jack is used to receive the sync signal and the other to send the sync signal. In this video, we will examine the Sync Out signal. We will do two experiments. In the first we will use only LEDs and in the second experiment we will use Arduino.
00:00 Intro
00:23 Sync Out
00:54 Experiment with LED
02:20 Experiment with Arduino
The first experiment is simple. We will use a Korg Volca synthesizer, an audio cable with 3.5 mm jacks, a socket, connecting wires and an LED with a resistor. The Sync Out signal has the shape of 5 V pulses with a length of 15 ms. Pulses are transmitted with a resolution of 2 PPQN (pulses per quarter note). That is, two pulses are sent during one quarter note. Because there is such an integrated circuit inside the synthesizer, we can connect an LED with a resistor to the Sync Out output and watch the LED start flashing. Let's put it all together and look at what the signal visualized by the LED will look like. Now I turn on the synthesizer and the LED lights up immediately. And after a while it starts blinking evenly. The flashing speed depends on the set tempo. Did you notice anything interesting? As soon as I turned on the synthesizer, the first pulse lasted a few seconds, and then the signals followed, even though I didn't turn on the internal sequencer in the synthesizer.
Let's go to the second experiment. We will use the Arduino and its ability to respond on some pins to an external signal. We connect the electrical circuit very similarly to the previous case. And we load a program into Arduino that responds to the Sync Out signal by an interrupt. I will not provide details about the program, you can read them in the attached article and source code. You can find both hypertexts in the description below the video. Let's repeat the previous experiment and you will see that the Arduino responds to an external interrupt and displays the result on the connected LED. The only difference is that the LED is a little brighter. But only because, thanks to the Arduino, a slightly larger current flows through the LED. Let's repeat the experiment with other synthesizers and you will see that they all behave roughly the same, the only difference being the length of the first pulse, which depends on the initialization of the program in the microcontroller, which is located in each synthesizer.
Links:
www.arduinoslovakia.eu/blog/2...
github.com/RoboUlbricht/ardui...
Music:
Robo Ulbricht - Intro - / arduino-video-intro-02
Frédéric Chopin - Waltz in A minor, B. 150 - / frederic-chopin-waltz-...
Robo Ulbricht - Ostinato - / ostinato
Robo Ulbricht - Sign in the Sky - / sign-in-the-sky