Luke's Cricket Chirper

What I wanted to learn, and why it interested me: I wanted to learn how to output custom sounds through my computer. I thought this would be interesting because I could play funny sounds at my friends.

Process and reflection: 

I started off by promoting ChatGPT on the resources and code I would need to put together this cricket chirper. I downloaded the .mp3 file to my microSD card and uploaded the code to the Arduino Uno. When I first set up my circuit, the chirping sound worked pretty quickly; however, I had to add the button component for the technical training. I spent a lot of time trying to get that to work, only to realize I had mixed up my ground and power strips on my breadboard. Zach's magical presence also helped get the thing to work. To progress the interaction, I soldered a latching switch, so that the sound would be continuous as long as the latching switch was held. Finally, I switched the initial button out with the latching switch I soldered extension wires to, which worked quite well. However, troubleshooting with the electrical circuit stuff proved to be difficult, and I found the most consistent method to get it to work was pressing the reset button. 

I definitely re-learned how tough troubleshooting hardware problems is and on top of that, how helpful ChatGPT can be with that (surprisingly, it is not helpful at all.) I guess this makes a pretty compelling case on why I need to really get a firm understanding of how to do Physical Computing.

/*

    60-223 Intro to Physical Computing, fall 2025

    Domain-specific Skill Building exercise: Luke's Cricket Chirper

    The program waits for a button press and plays an audio track on the DFPlayer Mini .mp3 reader. The button is wired so when a circuit to ground is completed, the Arduino detects a LOW signal. Each time the button is pressed, the Arduino sends a command to the DFPlayer to play the first audio file on the SD card (0001.mp3). A short delay prevents multiple triggers from one press.

    Pin mapping:

    Arduino pin | role  | details

    ------------------------------

    2             input   latching button

    10            output  attached to dfminiplayer read 

    11            input attached to dfminiplayer transfer

    Released to the public domain by the author, January 2024

    Robert Zacharias, rzachari@andrew.cmu.edu

*/

//sourced 100% from CHATGPT on September 29th, 2025

#include <SoftwareSerial.h>

#include <DFRobotDFPlayerMini.h>

SoftwareSerial mySerial(10, 11); // TX (10), RX (11)

DFRobotDFPlayerMini myDFPlayer;

const int buttonPin = 2;

void setup() {

 pinMode(buttonPin, INPUT_PULLUP); // button to GND when pressed

 mySerial.begin(9600);

 Serial.begin(9600);

 if (!myDFPlayer.begin(mySerial)) {

   Serial.println("DFPlayer not detected!");

   while (true);

 }

 myDFPlayer.volume(15); // set volume (0–30)

 Serial.println("System ready. Press button to play cricket sound.");

}

void loop() {

 if (digitalRead(buttonPin) == LOW) { // button pressed

   myDFPlayer.play(1); // play "0001.mp3"

   delay(1000);        // debounce + prevent retrigger

 }

}