Typing on lcd like calculator

Projects General Guidance
1

Hello, I have been trying to make my lcd type like a calculator, when I type a number with my keypad it should start from the right and shift to the left everytime I press an operator or number.
The default is left to right.

I correctly shift num1 to go to the left when I keep adding numbers but the operator and num 2 overlap with num1.
Does anybody know how to do this? Thankyou!

if (currentVal == false) {
      num1 = num1 + keyPress;
      numLen1 = num1.length();
      lcdShift = 20 - numLen1;
      lcd.setCursor(lcdShift, 0);
      lcd.print(num1);
    } else {
      num2 = num2 + keyPress;
      numLen2 = num2.length();
      lcd.setCursor(lcdShift + 2, 0);
      lcd.print(num2);
      endOfOperation = true;
    }
  } else if ((keyPress == '+' || keyPress == '-' || keyPress == '*' || keyPress == '/' ) && currentVal == false && keyPress != NO_KEY)
  {
    if (currentVal == false) {
      currentVal = true;
      operatorr = keyPress;
      lcd.autoscroll();
      lcd.setCursor(lcdShift + 3, 0);
      lcd.print(operatorr);
2

Please post your best working or not working complete sketch,

It is hard to see how your logic works with no context.

a7

3

@adrianate

Did you check the set of instructions / functions the lcd libraries has to offer ?

In the datasheet of the lcd display, it does have a command to going from right to left. So I check the library and it does have a function ...
lcd.rightToLeft();

So you have to instruct the lcd the command lcd.rightToLeft(); after the command lcd.setCursor(15,0); ( location of the starting point ) than lcd.print('What Ever"); The default lcd mode is from Left to Right. So change to default if nessary.

4

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