Digital Dice

In the last project, we learned how to use 74HC595 to light up the LED Segment Display. Of course, we can expand on this basis to make it more interesting.

Here, we will add a button to the previous project to make a digital dice. When the button is pressed, the 7 segment display will randomly show 1-6.

Schematic

Wiring

Code

When the program starts running, every time you press the button, the digital tube will randomly display a number from 1 to 6.

How it works?

SEGCODE = [0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f]

First, define a hexadecimal array to represent the number from 0 to 9 displayed by the 7 segment display.

if (digitalRead(button)==HIGH){
    dice = random(1,7);
}

When the value of the button is HIGH, i.e. the key has been pressed, the random() function is called to generate a random number from 1 to 6 to be stored in the variable dice.

• random

The following table shows the codes corresponding to these numbers.

Glyph Code

Numbers	Binary Code	Hex Code
0	00111111	0x3f
1	00000110	0x06
2	01011011	0x5b
3	01001111	0x4f
4	01100110	0x66
5	01101101	0x6d
6	01111101	0x7d
7	00000111	0x07
8	01111111	0x7f
9	01101111	0x6f

dice = random(1,7) the random function generates pseudo-random numbers from 1 to 6(Exclude 7).

digitalWrite(STcp,LOW); //ground ST_CP and hold low for as long as you are transmitting
shiftOut(DS,SHcp,MSBFIRST,datArray[dice]);
digitalWrite(STcp,HIGH); //pull the ST_CPST_CP to save the data
delay(100); //wait for a second

Display the corresponding number on the 7 segment display via shiftOut() function.