Published June 30, 2020

Visualized Hand Washing Timer

A Visualized Hand Washing Timer to ensure that you wash your hands long enough to achieve disinfection.

BeginnerFull instructions provided1 hour365

Things used in this project

Hardware components

Elegoo Arduino Nano V3+

Elegoo MAX7219 Module

Elegoo 9V Battery

Elegoo Ultrasonic Sensor

Slide Switch

Wire

Story

Stay home, stay creative. To swipe away boredom, encourage making, and bring ideas for more quality quarantine days, we made a series of new project tutorials involved with #Arduino & #3DPrinting, which are all low-cost solutions that respond to the COVID-19 pandemic.

This is the 3rd one: A Visualized Hand Washing Timer to ensure that you wash your hands long enough to achieve disinfection.

Please watch the video to find the step-by-step tutorial:

Download code, stl. and schematic here: https://bit.ly/3ar2uji

Code

Visualized Hand Washing Timer

#include "LedControl.h"
#include "SR04.h"


#define TRIG_PIN 11
#define ECHO_PIN 10


SR04 sr04 = SR04(ECHO_PIN, TRIG_PIN);
#define CARTIME 200
//DIN -9
//CS  -8
//CLk -7
LedControl lc = LedControl(9, 7, 8, 2);
byte Data2[] =
{ B00000000,
  B00000000,
  B00000000,
  B11111111,
  B00000000,
  B00000000,
  B00000000,
  B11111111,
};


byte tmp[8];
byte tmp2[8];
byte Data3[] =
{ B00000111,
  B00000111,
  B00000101,
  B11111111,
  B00000000,
  B00000000,
  B00000000,
  B11111111,
};


byte Data4[] =
{
  B00000000,
  B00000000,
  B00000000,
  B11111111,
  B11100000,
  B11100000,
  B10100000,
  B11111111,
};




int data[20][8] = {
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {0, 0, 0, 0, 0, 0, 0, 0},
  {1, 1, 1, 1, 1, 1, 1, 1}
};




void setup() {
  Serial.begin(9600);
  MAX7219_Init();
  lc.setIntensity(0, 1);
  lc.setIntensity(1, 1);
}


void loop() {


  if (sr04.Distance() <= 8 && sr04.Distance() >= 1) {
    while (data[3][1] != 1 && data[3][6] != 1) {
      int n;
      MAX7219_Display();
      MAX7219_Display_drop();
      delay(150);
      n = random(0, 2);
      if (n == 1)
        data[0][3] = 1;
      if (n == 0)
        data[0][4] = 1;
    }
    delay(150);
    lc.clearDisplay(0);
    lc.clearDisplay(1);
    MAX7219_Display_Car();
    MAX7219_Display_clear();
  }


}


void MAX7219_Display_clear() {
  for (int i = 0; i < 19; i++)
    for (int j = 0; j < 9; j++)
    {
      data[i][j] = 0;
    }
  for (int j = 0; j < 9; j++)
  {
    data[19][1] = 0;
  }
  MAX7219_Display();
}


void MAX7219_Display_Car()
{


  for (int j = 0; j < 8; j++)
  {
    lc.setRow(0, j, Data2[j]);
  }
  delay(CARTIME);


  memcpy(tmp, Data3, sizeof(Data3));
  for (int i = 0; i < 8; i++)
  {
    for (int j = 0; j < 8; j++)
    {
      lc.setRow(0, j, tmp[j]);
    }
    for (int i = 0; i < 8; i++)
    {
      lc.setRow(1, i, Data2[i]);
    }
    tmp[0] <<= 1;
    tmp[1] <<= 1;
    tmp[2] <<= 1;
    delay(CARTIME);
  }


  memcpy(tmp2, Data4, sizeof(Data4));
  for (int i = 0; i < 8; i++)
  {
    for (int j = 0; j < 8; j++)
    {
      lc.setRow(0, j, tmp2[j]);
    }
    tmp2[4] >>= 1;
    tmp2[5] >>= 1;
    tmp2[6] >>= 1;
    delay(CARTIME);
  }


  memcpy(tmp, Data3, sizeof(Data3));
  for (int i = 0; i < 8; i++)
  {
    for (int j = 0; j < 8; j++)
    {
      lc.setRow(1, j, tmp[j]);
    }
    for (int i = 0; i < 8; i++)
    {
      lc.setRow(0, i, Data2[i]);
    }
    tmp[0] <<= 1;
    tmp[1] <<= 1;
    tmp[2] <<= 1;
    delay(CARTIME);
  }


  memcpy(tmp2, Data4, sizeof(Data4));
  for (int i = 0; i < 8; i++)
  {
    for (int j = 0; j < 8; j++)
    {
      lc.setRow(1, j, tmp2[j]);
    }
    tmp2[4] >>= 1;
    tmp2[5] >>= 1;
    tmp2[6] >>= 1;
    delay(CARTIME);
  }
}
void MAX7219_Display_drop() {


  for (int i = 18; i > 0; i--) {


    for (int j = 0; j < 8; j++) {
      if (data[i][j] != 0 && data[i + 1][j] != 0 && data[i + 2][j] != 0) {
        if (j <= 3 && data[i + 1][j - 1] == 0) {
          Switch(&data[i][j], &data[i + 1][j - 1]);
        }
        if (j >= 4 && data[i + 1][j + 1] == 0) {
          Switch(&data[i][j], &data[i + 1][j + 1]);
        }
      }
      if (data[i][j] == 0 && data[i - 1][j] != 0) {
        Switch(&data[i][j], &data[i - 1][j]);
      }




    }
  }
}


void Switch(int *a, int *b) {
  *a ^= *b;
  *b ^= *a;
  *a ^= *b;
}
void MAX7219_Display()
{
  for (int j = 0; j < 8; j++)
  {
    lc.setRow(0, j, Int_array_to_byte(j));
  }


  for (int j = 8; j < 16; j++)
  {
    lc.setRow(1, j - 8, Int_array_to_byte(j));
  }
}
int Int_array_to_byte(int a)//
{
  int temp = 0;
  for (int i = 0; i < 8 ; i++)
  {
    int b = 1;
    for (int m = 0; m < (7 - i); m++) {


      b = b * 2;
    }
    temp = data[a + 3][i] * b + temp;


  }
  return temp;


}


void MAX7219_Init()
{
  for (int i = 0; i < 2; i++)
  {
    lc.shutdown(i, false);
    lc.setIntensity(i, 1);
    lc.clearDisplay(i);
  }
}

Credits

Elegoo Official

3 projects • 18 followers

Visualized Hand Washing Timer

Things used in this project

Hardware components

Story

Schematics