Need help with codes (continuity cable tester with lcd 16x2 i2C)

Projects Programming
16

Hi @TomGeorge
I play with the code, I got screen comes up but it stuck at "Cable Tester, Press Enc p/start" lcd.print. And when i remove lcd.print, i am stuck at lcd.print("Cable Tester"); on my display :slight_smile:
I just want to run this loop and test the wire automatically when i short 2 pins. Here's my new code using HD44780.

#include <Wire.h>
#include <LCD.h>
#include <LiquidCrystal_I2C.h>

#include <hd44780.h>
const uint8_t i2cAddr = 0x27;
const int rs=0, rw=1, en=2, db4=4, db5=5, db6=6, db7=7, bl=3;
typeof(POSITIVE) blpol=POSITIVE; // backlight polarity level
LiquidCrystal_I2C lcd(i2cAddr, en, rw, rs, db4, db5, db6, db7, bl, blpol);
//pins

#define sizeTest 4

int endA[sizeTest] = {4, 5, 6, 7}; //pins end A
int endB[sizeTest] = {8, 9, 10, 11}; //pins endB
int pSwitch = A0;
int pEncA = A1;
int pEncB = A2;


//results
int result[sizeTest];
int test[sizeTest];
int counter[sizeTest];
bool fail;

void setup() {

  Serial.begin(115200); //serial used for debugging only
  lcd.begin(16, 2);

  //setup pins
  for (int i = 0; i < sizeTest; i++) {
    pinMode(endA[i], OUTPUT);//set output pins (end A)
    pinMode(endB[i], INPUT_PULLUP);//set input pins (end B)
  }
  pinMode(pSwitch, INPUT_PULLUP);
  lcd.clear();
  lcd.print("Cable Tester");
  lcd.setCursor(0, 1);
  lcd.print("Press Enc p/ Start");
}

void loop() {
  //run the test
  if (!digitalRead(pSwitch)) {
    runTest_4x1();
    delay(200);
  }
}

void runTest_4x1() {

  // add space for null terminator
  char s[sizeTest+1] = "0000";

  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Testing 4 Pin");
  lcd.setCursor(0, 1);

  // re-initialize reqired variables
  fail = false;
  for (int i = 0; i < sizeTest; i++){
    result[i] = -1;
    test[i] = -1;
    counter[i] = -1;
  }

  for (int i = 0; i < sizeTest; i++) {
    counter[i] = 0;
    for (int j = 0; j < 4; j++) {
      digitalWrite(endA[i], LOW); //set all outputs to LOW
    }
    for (int j = 0; j < sizeTest; j++) { //check for crossed / open circuits vs closed, good, circuits
      digitalWrite(endA[j], HIGH); //scan across the inputs in turn
      test[i] = digitalRead(endB[i]); //read the output
      if (test[i] == 1 && j != i) { //crossed or open circuit
        counter[i]++;
        result[i] = 8 + j;
      }
      else if (test[i] == 1 && j == i && result[i] < 8 ) { //Good, closed circuit
        result[i] = 0;
      }
      digitalWrite(endA[j], LOW);
      //debugging
      /*
        Serial.print("test input core  ");
        Serial.print(i);
        Serial.print(" with output core  ");
        Serial.print(j);
        Serial.print(" test =");
        Serial.print(test[i]);
        Serial.print(" counter =");
        Serial.println(counter[i]);
      */
    }
    Serial.print("Core ");
    Serial.print(i);
    Serial.print(" result = ");
    if (result[i] == 0) {
      Serial.println(" 1");
      s[i] = '1';
    }
    else if (counter[i] == 3) {
      Serial.println(" O");
      s[i] = '0';
      fail = true;
    }
    else {
      Serial.println(" X");
      s[i] = 'X';
      fail = true;
    }
  }
  lcd.print(s);
  lcd.setCursor(0, 2);

  if (fail) {
    Serial.println("DEFECT");
    lcd.print("DEFECT");
  }
  else {
    Serial.println("CABLE OK");
    lcd.print("CABLE OK");
  }
  Serial.println();
  lcd.setCursor(0, 2);
  lcd.print("Press Enc P/ Start");
}

Thanks