Week 4 – Marquee Letter PCB Fab

Over the last week I took my PCB design from Eagle to Bantam Tools for PCB milling.

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I ended up having to mill the board twice. My first attempt had a short that I wasn’t able to locate. Milling on my second attempt went much better!

Next I moved on to SMD soldering with solder paste and heat gun.

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To program my board I ended up using an SOIC8 test clip I ordered from Amazon that fit nicely into the programming jig we made in class.

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Since my board includes a piezo buzzer my intention was for it to generate sound in response to registering a touch from the capacitive sensor. Taking inspiration from Rick and Morty the buzzer plays “Human Music” when touched.

Here is my Arduino sketch:

/*
  Marquee Assigment
  by Brandon Roots
  
  Homemade Hardware
  ITP Spring 2022
*/

#include <CapacitiveSensor.h>

CapacitiveSensor   cs_4_3 = CapacitiveSensor(3,4); 
const int buzzer = 2; //buzzer to ATTINY85 pin 2
long touchCounter = 0;

// the setup function runs once when you press reset or power the board
void setup() {
  // initialize digital pin LED_BUILTIN as an output.
  pinMode(0, OUTPUT);
  cs_4_3.set_CS_AutocaL_Millis(0xFFFFFFFF);     // turn off autocalibrate on channel 1 - just as an example
}

// the loop function runs over and over again forever
void loop() {

  long total1 =  cs_4_3.capacitiveSensor(30);

  if(total1 > 100){
    if(touchCounter == 0){
      touchCounter = millis();
    }
    digitalWrite(0, HIGH);   // turn the LED on (HIGH is the voltage level)
    humanMusic();
  }
  else {
    //digitalWrite(0, LOW);    // turn the LED off by making the voltage LOW
    pulseLight();
    noTone(buzzer);     // Stop sound...
    if(touchCounter > 0){
      touchCounter = 0;
    }
  }              
}

void humanMusic(){
  int tempo = 120;
  int millisTempo = 60000/tempo;
  int beat = millis() - touchCounter;

  if(beat%(millisTempo*4) < (millisTempo * 0.25)){
    tone(buzzer, 523); // Send signal... (523,  587, 523)
  }
  else if(beat%(millisTempo*4) > (millisTempo * 1) && beat%(millisTempo*4) < (millisTempo * 1.25)){
    tone(buzzer, 587); // Send signal... (523,  587, 523)
  }
  else if(beat%(millisTempo*4) > (millisTempo * 2) && beat%(millisTempo*4) < (millisTempo * 2.25)){
    tone(buzzer, 523); // Send signal... (523,  587, 523)
  }
  else{
    noTone(buzzer);
  } 
}

void pulseLight(){
  int brightness = millis()%2000;
  int mappedBrightness = 0;
  if(brightness < 1000){
    mappedBrightness = int(map(brightness, 0, 1000, 1, 50));
  } else {
    mappedBrightness = int(map(brightness, 1000, 2000, 50, 1));
  }
  analogWrite(0, mappedBrightness);
}