Week 9:Input Devices

This week describes my understanding of how to use Input Devices. It also includes how to generate an analog output (PWM) using pin 9, how to use an oscilloscope and multimeter for analysis, and how to integrate different sesnor with the microcontroller.

Interpret a Signal

We generate an analog output (PWM) using pin 9. A LED is connected to see the signal effect, and the oscilloscope and multimeter are used for analysis.

                void setup() {
                pinMode(9, OUTPUT);
                }

                void loop() {
                for (int u = 0; u < 255; u++){
                    analogWrite(9, u);
                    delay(50);
                }
                }
            

Video Demonstration

For Group Assignment Refer here

Joystick Module

The Joystick Module consists of two potentiometers, each controlling an axis (X and Y).

Reading Joystick Module

Connect the joystick to Arduino: A0 and A1 for analog readings, pin 2 for the button.

                    int x_Pin = A0;
                    int y_Pin = A1;
                    int button_Pin = 2;

                    void setup(){
                        Serial.begin(9600);
                        pinMode(button_Pin, INPUT_PULLUP);
                   }

                    void loop(){
                        Serial.print("X: "); Serial.print(analogRead(x_Pin));
                        erial.print("\tY: "); Serial.print(analogRead(y_Pin));
                        Serial.print("\tButton: "); Serial.println(digitalRead(button_Pin));
                    delay(100);
                    }
                

Joystick Axis Values

Axis X	Axis Y
Up	1023	527
Down	0	527
Right	512	1023
Left	512	0
Center	512	527

Video Demonstration

Temperature Sensor LM35

The LM35 is an analog temperature sensor with an output range of 0V to 1.5V.

                float temp = 0.0;
                int temp_Pin = 0;

                void setup(){
                    Serial.begin(9600);
                }
                void loop(){
                    temp = analogRead(temp_Pin);
                    Serial.print("temperature: ");
                    Serial.println(temp);
                    delay(100);
                }
            

Converting to Celsius

float temp_C = (5.0 * temp * 100.0) / 1024.0;

Ultrasonic Sensor HC-SR04

The HC-SR04 sensor calculates distance using ultrasonic waves.

            const int Trig = 2;
            const int Echo = 3;
            float tim = 0.0;
            float dist = 0.0;

            void setup(){
                Serial.begin(9600);
                pinMode(Trig, OUTPUT);
                pinMode(Echo, INPUT);
                digitalWrite(Trig, LOW);
            }

            void loop(){
                digitalWrite(Trig, HIGH);
                delayMicroseconds(10);
                digitalWrite(Trig, LOW);
                tim = pulseIn(Echo, HIGH);
                dist = tim / 59.0;
                Serial.print("Distance: ");
                Serial.print(dist);
                Serial.println(" cm");
                delay(100);
            }
        
        

Learning Summary

• Learned about the basics of Arduino and its components.
• Understood about the Xiao - Seeed Studio Esp32C3
• Learned how to use the LiquidCrystal library to control an LCD screen.
• Implemented a simple timer using the LCD screen.

Download the Files

waveform_analysis

That’s all for now!