balance.ino

#include <HX711_ADC.h>
#include <EEPROM.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#define SCREEN_WIDTH 128 
#define SCREEN_HEIGHT 32 
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

const int HX711_dout = 4; //mcu > HX711 dout pin
const int HX711_sck = 5; //mcu > HX711 sck pin
HX711_ADC LoadCell(HX711_dout, HX711_sck);

int tpin = 3;
const int calVal_eepromAdress = 0;
long t;

void setup() {
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  display.clearDisplay();
  display.setTextSize(2);
  display.setTextColor(WHITE);
  display.setCursor(0, 8);
  display.println("  BALANCE");
  display.display();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0, 25); 
  display.println("EDISON SCIENCE CORNER");
  display.display();
  delay(4000);
  display.clearDisplay();
  Serial.begin(57600);
  delay(10);
  Serial.println();
  Serial.println("Starting...");
  pinMode(tpin, INPUT_PULLUP);
  LoadCell.begin();
  float calibrationValue; // calibration value (see example file "Calibration.ino")
  calibrationValue = 696.0; // uncomment this if you want to set the calibration value in the sketch
#if defined(ESP8266)|| defined(ESP32)
  //EEPROM.begin(512); // uncomment this if you use ESP8266/ESP32 and want to fetch the calibration value from eeprom
#endif
  EEPROM.get(calVal_eepromAdress, calibrationValue); // uncomment this if you want to fetch the calibration value from eeprom
  long stabilizingtime = 2000; // preciscion right after power-up can be improved by adding a few seconds of stabilizing time
  boolean _tare = true; //set this to false if you don't want tare to be performed in the next step
  LoadCell.start(stabilizingtime, _tare);
  if (LoadCell.getTareTimeoutFlag())
  {
    Serial.println("Timeout, check MCU>HX711 wiring and pin designations");
    while (1);
  }
  else
  {
    LoadCell.setCalFactor(calibrationValue); // set calibration value (float)
    Serial.println("Startup is complete");
  }
}
void loop() {
  static boolean newDataReady = 0;
  const int serialPrintInterval = 0; //increase value to slow down serial print activity
  // check for new data/start next conversion:
  if (LoadCell.update()) newDataReady = true;
  // get smoothed value from the dataset:
  if (newDataReady)
  {
    if (millis() > t + serialPrintInterval) {
      float i = LoadCell.getData();
      Serial.print("Load_cell output val: ");
      Serial.println(i);
      newDataReady = 0;
      t = millis();
       display.clearDisplay();
      display.setTextSize(3);
  display.setTextColor(WHITE);
  display.setCursor(10, 10);
  display.println(i);
  display.display();
  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(115,20);
  display.println("gm");
  display.display();
   delay(10);
      
  }
  
  if (digitalRead(tpin) == LOW) {
    LoadCell.tareNoDelay();
  }
  // check if last tare operation is complete:
  if (LoadCell.getTareStatus() == true) {
    display.clearDisplay();
    display.setTextSize(2);
    display.setTextColor(WHITE);
    display.setCursor(0, 0); 
    display.println("Tare        complete");
    display.display();
    delay(1000);
    display.clearDisplay();
  }
  }
}