LiquidCrystal change custom char

[TobiasHewel]

Hi, I want to change a custom char, mid-way through a sketch. And the reason that I don't just use another char, is that I have to use all 8 chars, and I need them to change to a lot more than 8 states.
So far, I have made this:

#include <LiquidCrystal.h> 

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

byte customChar[8] = {
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b10101,
  0b00000
};

void setup() {
  lcd.createChar(0, customChar);
  lcd.begin(16, 2);
}

void loop() {
  lcd.write((uint8_t)0);
  customChar[8] = {
    0b00000,
    0b00000,
    0b00000,
    0b00000,
    0b00100,
    0b00000,
    0b10100,
    0b00000 
  };
  delay(3000);
}

But I get error:

C:\Users\admin\AppData\Local\Temp\arduino_modified_sketch_362623\sketch_jun26a.ino: In function 'void loop()':
sketch_jun26a:32:3: error: cannot convert '<brace-enclosed initializer list>' to 'byte {aka unsigned char}' in assignment
   };
   ^
exit status 1
cannot convert '<brace-enclosed initializer list>' to 'byte {aka unsigned char}' in assignment

I don't know how to fix this.

[UKHeliBob]

  customChar[8] =
  {
    0b00000,
    0b00000,
    0b00000,
    0b00000,
    0b00100,
    0b00000,
    0b10100,
    0b00000
  };

You cannot define all 8 elements of an array like this in a function, only when it is first declared

The easiest way to do what you want is to declare and define 2 arrays, each with the custom character definition and copy the required one to a third array that you use in the function

Something like this (untested)

#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

byte customChar_1[8] =
{
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b10101,
  0b00000
};

byte customChar_2[8] =
{
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b00100,
  0b00000,
  0b10100,
  0b00000
};

byte activeCustomChar[8];

void setup()
{
  memcpy(activeCustomChar, customChar_1, 8);
  lcd.createChar(0, activeCustomChar);
  lcd.begin(16, 2);
}

void loop()
{
  lcd.write((uint8_t)0);
  delay(3000);
}

Note that if a custom character is currently displayed on screen then changing its definition will change what is displayed even if it was previously printed with the previous definition

[anon73444976]

@TobiasHewel

customChar[8] = {

At this point, you have an array called "customChar", but it has only eight elements, so to assign anything to the ninth element is clearly A Bad Thing.

Just create a new array, and call createChar with it as a parameter.

[johnwasser]

To change the glyph (image) of Custom Character 0 you will have to call "lcd.createChar(0, newGlyph);" again.

#include <LiquidCrystal.h>

LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

byte Glyph0A[8] =
{
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b10101,
  0b00000
};

byte Glyph0B[8] =
{
  0b00000,
  0b00000,
  0b00000,
  0b00000,
  0b00100,
  0b00000,
  0b10100,
  0b00000
};

void setup()
{
  lcd.begin(16, 2);
  lcd.write((uint8_t)0);
}

void loop()
{
  lcd.createChar(0, Glyph0A);
  delay(3000);
  lcd.createChar(0, Glyph0B);
  delay(3000);
}

[groundFungus]

If you replace a custom character in mid sketch, the new character will replace all instances of the original character when the display is updated.