Add custom character example

Added missing custom character example.

Author: karlsoderby

content/learn/04.electronics/03.lcd-displays/lcd-displays.md

@@ -1010,4 +1010,164 @@ void loop() {
 
   thisChar++;
 }
+```
+
+### Custom Character
+
+This example demonstrates how to add custom characters on an LCD  display. 
+
+Note that this example requires an additional potentiometer:
+- Outer pins connected to 5V and GND.
+- Inner pin (wiper) connected to A0.
+
+This potentiometer controls the `delayTime` variable.
+
+```arduino
+/*
+  LiquidCrystal Library - Custom Characters
+
+ Demonstrates how to add custom characters on an LCD  display.
+ The LiquidCrystal library works with all LCD displays that are
+ compatible with the  Hitachi HD44780 driver. There are many of
+ them out there, and you can usually tell them by the 16-pin interface.
+
+ This sketch prints "I <heart> Arduino!" and a little dancing man
+ to the LCD.
+
+  The circuit:
+ * LCD RS pin to digital pin 12
+ * LCD Enable pin to digital pin 11
+ * LCD D4 pin to digital pin 5
+ * LCD D5 pin to digital pin 4
+ * LCD D6 pin to digital pin 3
+ * LCD D7 pin to digital pin 2
+ * LCD R/W pin to ground
+ * 10K potentiometer:
+ * ends to +5V and ground
+ * wiper to LCD VO pin (pin 3)
+ * 10K poterntiometer on pin A0
+
+ created 21 Mar 2011
+ by Tom Igoe
+ modified 11 Nov 2013
+ by Scott Fitzgerald
+ modified 7 Nov 2016
+ by Arturo Guadalupi
+
+ Based on Adafruit's example at
+ https://github.com/adafruit/SPI_VFD/blob/master/examples/createChar/createChar.pde
+
+ This example code is in the public domain.
+ http://www.arduino.cc/en/Tutorial/LiquidCrystalCustomCharacter
+
+ Also useful:
+ http://icontexto.com/charactercreator/
+
+*/
+
+// include the library code:
+#include <LiquidCrystal.h>
+
+// initialize the library by associating any needed LCD interface pin
+// with the arduino pin number it is connected to
+const int rs = 12, en = 11, d4 = 5, d5 = 4, d6 = 3, d7 = 2;
+LiquidCrystal lcd(rs, en, d4, d5, d6, d7);
+
+// make some custom characters:
+byte heart[8] = {
+  0b00000,
+  0b01010,
+  0b11111,
+  0b11111,
+  0b11111,
+  0b01110,
+  0b00100,
+  0b00000
+};
+
+byte smiley[8] = {
+  0b00000,
+  0b00000,
+  0b01010,
+  0b00000,
+  0b00000,
+  0b10001,
+  0b01110,
+  0b00000
+};
+
+byte frownie[8] = {
+  0b00000,
+  0b00000,
+  0b01010,
+  0b00000,
+  0b00000,
+  0b00000,
+  0b01110,
+  0b10001
+};
+
+byte armsDown[8] = {
+  0b00100,
+  0b01010,
+  0b00100,
+  0b00100,
+  0b01110,
+  0b10101,
+  0b00100,
+  0b01010
+};
+
+byte armsUp[8] = {
+  0b00100,
+  0b01010,
+  0b00100,
+  0b10101,
+  0b01110,
+  0b00100,
+  0b00100,
+  0b01010
+};
+
+void setup() {
+  // initialize LCD and set up the number of columns and rows:
+  lcd.begin(16, 2);
+
+  // create a new character
+  lcd.createChar(0, heart);
+  // create a new character
+  lcd.createChar(1, smiley);
+  // create a new character
+  lcd.createChar(2, frownie);
+  // create a new character
+  lcd.createChar(3, armsDown);
+  // create a new character
+  lcd.createChar(4, armsUp);
+
+  // set the cursor to the top left
+  lcd.setCursor(0, 0);
+
+  // Print a message to the lcd.
+  lcd.print("I ");
+  lcd.write(byte(0)); // when calling lcd.write() '0' must be cast as a byte
+  lcd.print(" Arduino! ");
+  lcd.write((byte)1);
+
+}
+
+void loop() {
+  // read the potentiometer on A0:
+  int sensorReading = analogRead(A0);
+  // map the result to 200 - 1000:
+  int delayTime = map(sensorReading, 0, 1023, 200, 1000);
+  // set the cursor to the bottom row, 5th position:
+  lcd.setCursor(4, 1);
+  // draw the little man, arms down:
+  lcd.write(3);
+  delay(delayTime);
+  lcd.setCursor(4, 1);
+  // draw him arms up:
+  lcd.write(4);
+  delay(delayTime);
+}
 ```