#include <HX711.h>
#include <TM1637.h>

#define TACT_SW_PIN       2
#define TM1637_A_CLK_PIN  4
#define TM1637_A_DIO_PIN  5
#define TM1637_B_CLK_PIN  6
#define TM1637_B_DIO_PIN  7
#define TM1637_DIGIT      4
#define HX711_SCK_PIN     A0
#define HX711_DT_PIN      A1
#define HX711_OFFSET      2.381

TM1637 TM1, TM2;
HX711 scale;
volatile long tare = 0;

void callbackTactSw() {
  tare = scale.read() * HX711_OFFSET;
}

void setup() {
  TM1.begin(TM1637_A_CLK_PIN, TM1637_A_DIO_PIN, TM1637_DIGIT);
  TM1.displayClear();
  TM1.setBrightness(7);
  TM2.begin(TM1637_B_CLK_PIN, TM1637_B_DIO_PIN, TM1637_DIGIT);
  TM2.displayClear();
  TM2.setBrightness(7);
  scale.begin(HX711_DT_PIN, HX711_SCK_PIN);
  attachInterrupt(digitalPinToInterrupt(TACT_SW_PIN), callbackTactSw, FALLING);
}

void loop() {
  long weight = scale.read() * HX711_OFFSET;
  TM1.displayInt(weight);
  if ((weight - tare) < -1000) {
    TM2.displayFloat((weight - tare) / 100, 1);
  } else {
    TM2.displayInt(weight - tare);
  }
  delay(100);
}