## Arduino Program to Display 3, 6 and 9 in an SSD by 7490 and 4511 (Part 9 of 9)

by realfinetime  |  in Seven Segment Display at  12:28

Arduino program to display "3", "6" and "9" in the seven segment display is given below. Complete the circuit and upload the following program to your arduino board.

```int INPUT_A = 13;
int R01_and_R02 = 12;
int LE = 10;

int i=0;

// the setup routine runs once when you press reset:
void setup() {
// initialize the digital pin as an output.
pinMode(INPUT_A, OUTPUT);
pinMode(R01_and_R02, OUTPUT);
pinMode(LE, OUTPUT);
}

// the loop routine runs over and over again forever:
void loop() {
digitalWrite(R01_and_R02, HIGH);
digitalWrite(LE, LOW);
digitalWrite(R01_and_R02, LOW);
for(i=0;i<3;i++)
{
digitalWrite(INPUT_A, HIGH);
digitalWrite(INPUT_A, LOW);
}
digitalWrite(LE, HIGH);

delay(1000);

digitalWrite(R01_and_R02, HIGH);
digitalWrite(LE, LOW);
digitalWrite(R01_and_R02, LOW);
for(i=0;i<6;i++)
{
digitalWrite(INPUT_A, HIGH);
digitalWrite(INPUT_A, LOW);
}
digitalWrite(LE, HIGH);

delay(1000);

digitalWrite(R01_and_R02, HIGH);
digitalWrite(LE, LOW);
digitalWrite(R01_and_R02, LOW);
for(i=0;i<9;i++)
{
digitalWrite(INPUT_A, HIGH);
digitalWrite(INPUT_A, LOW);
}
digitalWrite(LE, HIGH);
delay(1000);
}
```

Output will be 3, 6 and 9 displayed in the seven segment display.

Algorithm of program is given below.

Make LE of 4511 LOW, so that any change in input (D0 - D3) of 4511 will make changes in the output (Qa - Qg) of 4511 and hence in the seven segment display.

Send HIGH to R0(1) and R0(2) of 7490 to reset 7490. This is to display "0" in the seven segment display.

Send LOW to R0(1) and R0(2) to convert 7490 from reset mode to count mode.

Send three HIGH to LOW transitions to INPUT A of 7490 using an "i" loop. This will display "3" in the seven segment display.

Make LE of 4511 HIGH, so that further changes in input (D0 - D3) of 4511 will not change the output (Qa - Qg) of 4511. That is, number displayed will not change in further HIGH to LOW transitions of clock input (INPUT A of 7490).

Delay for 1 second.

Make LE of 4511 LOW, so that any change in input (D0 - D3) of 4511 will make changes in the output (Qa - Qg) of 4511 and hence in the seven segment display.

Send HIGH to R0(1) and R0(2) of 7490 to reset 7490. This is to display "0" in the seven segment display.

Send LOW to R0(1) and R0(2) to convert 7490 from reset mode to count mode.

Send six HIGH to LOW transitions to INPUT A of 7490 using an "i" loop. This will display "6" in the seven segment display.

Make LE of 4511 HIGH, so that further changes in input (D0 - D3) of 4511 will not change the output (Qa - Qg) of 4511. That is, number displayed will not change in further HIGH to LOW transitions of clock input (INPUT A of 7490).

Delay for 1 second.

Make LE of 4511 LOW, so that any change in input (D0 - D3) of 4511 will make changes in the output (Qa - Qg) of 4511 and hence in the seven segment display.

Send HIGH to R0(1) and R0(2) of 7490 to reset 7490. This is to display "0" in the seven segment display.

Send LOW to R0(1) and R0(2) to convert 7490 from reset mode to count mode.

Send nine HIGH to LOW transitions to INPUT A of 7490 using an "i" loop. This will display "9" in the seven segment display.

Make LE of 4511 HIGH, so that further changes in input (D0 - D3) of 4511 will not change the output (Qa - Qg) of 4511. That is, number displayed will not change in further HIGH to LOW transitions of clock input (INPUT A of 7490).

Delay for 1 second.