Experimental & Learning Shield for Arduino UNO

1/*
2  Experimental Shield Displays "HELLO" - Arduino UNO - - - - L. Thomas - December 2023
3  
4*/
5//  The 7 lines below give names to the UNO pins 3, 8, 9, 10, 11, 12, and 13
6int GrnLED = 3;     // pin 3 is connected to the GREEN LED
7int RedLED = 13;    // pin 13 is connected to the RED LED
8int DataIn = 8;     // pin 8 is serial in data for the shift register
9int ClkIn = 9;      // pin 9 clocks in the data from pin 8
10int RegClk = 10;    // pin 10 clocks byte of data to the outputs
11int OutEnable = 11; // pin 11, when LOW, enables the output (HIGH disables)
12int Clear = 12;     // pin 12, when LOW, clears the shift register to all zeros
13//
14byte LtrH = 118;    // Value that will display an H
15byte LtrE = 121;    // Value that will display an E
16byte LtrL = 56;     // Value that will display an L
17byte LtrO = 63;     // Value that will display an O (or zero)
18//
19// The setup routine runs once during start-up or when RESET is pressed.
20// The setup commands are inside the pair of curly braces following "void setup()"
21void setup()
22{
23  pinMode(GrnLED, OUTPUT);     // This sets pin 3 as an output
24  pinMode(RedLED, OUTPUT);     // This sets pin 13 as an output
25  pinMode(DataIn, OUTPUT);     // This sets pin 8 as an output
26  pinMode(ClkIn, OUTPUT);      // This sets pin 9 as an output
27  pinMode(RegClk, OUTPUT);     // This sets pin 10 as an output
28  pinMode(OutEnable, OUTPUT);  // This sets pin 11 as an output
29  pinMode(Clear, OUTPUT);      // This sets pin 12 as an output
30//
31  digitalWrite(RedLED, LOW);    // This turns off the RED LED
32  digitalWrite(GrnLED, LOW);    // This turns off the GREEN LED
33  digitalWrite(DataIn, LOW);    // Make data pin a zero (LOW)
34  digitalWrite(ClkIn, LOW);     // Initialize the input clock to LOW status
35  digitalWrite(RegClk, LOW);    // Shift register clock initialized LOW
36  digitalWrite(OutEnable, LOW); // Shift register output is enabled
37  digitalWrite(Clear, HIGH);    // Initialize the CLEAR pin to HIGH (not cleared)
38}
39// Now that the setup has been done, the main loop is started
40// **** MAIN LOOP ***************************************************************
41void loop ()
42{
43  shiftOut(DataIn, ClkIn, LSBFIRST, LtrH);  //This loads an H into the shift register
44  DisplayON();                              //Display it
45  shiftOut(DataIn, ClkIn, LSBFIRST, LtrE);  //This loads an E into the shift register
46  DisplayON();                              //Display it
47  shiftOut(DataIn, ClkIn, LSBFIRST, LtrL);  //This loads an L into the shift register
48  DisplayON();                              //Display it
49  shiftOut(DataIn, ClkIn, LSBFIRST, LtrL);  //This loads an L into the shift register
50  DisplayON();                              //Display it
51  shiftOut(DataIn, ClkIn, LSBFIRST, LtrO);  //This loads an O into the shift register
52  DisplayON();                              //Display it
53  digitalWrite(GrnLED, LOW);                //Turn off the green LED
54  digitalWrite(RedLED, HIGH);               //Turn on the red LED
55  delay(2000);                              //Pause 2 seconds before repeating
56  digitalWrite(RedLED, LOW);                //Turn off the red LED
57  digitalWrite(GrnLED, HIGH);               //Turn on the green LED -- End of the Loop
58}
59void DisplayON()                            //This function activates the display
60{
61  digitalWrite(RegClk, HIGH);               //Clock the data to the output register
62  digitalWrite(RegClk, LOW);                //Put Clock signal back low
63  digitalWrite(OutEnable, LOW);             //Enable the outputs to drive the segments
64  delay(300);                               //Give some time to see the result
65  digitalWrite(OutEnable, HIGH);            //Disable the outputs (Turn off the display)
66  delay(40);                                //Leave it off briefly
67  digitalWrite(ClkIn, LOW);                 //Be sure clock is initialized to LOW status
68}