Week 9 - Input Devices

Assignment

Group assignment:

Probe an input device(s)'s analog levels and digital signals Document your work on the group work page and reflect on your individual page what you learned

Individual assignment:

Measure something: add a sensor to a microcontroller board that you have designed and read it.

Summary

This week, I explored input devices, specifically a digital Hall sensor. The goal was to understand how the sensor detects magnetic fields and integrates with a microcontroller. I used a Hall sensor with three pins: VCC, GND, and SIG (digital output), interfacing it with my PCB board from electronic production week.

Connection

Hall Sensor Digital Pin (SIG) to D3 on Xiao RP2040
VCC to 3.3V
GND to GND

I monitored the sensor data through the Arduino Serial Monitor while testing it with a magnet to observe changes in the readings.

Codes

        
                #define LED_PIN D1  
                #define BUTTON_PIN D2  
                #define HALL_SENSOR_PIN A3  

                bool ledState = false;

                void setup() {
                    pinMode(LED_PIN, OUTPUT);
                    pinMode(BUTTON_PIN, INPUT_PULLUP);

                    Serial.begin(115200);
                    Serial.println("Setup complete");
                }

                void loop() {
                    int buttonState = digitalRead(BUTTON_PIN);
                    int hallValue = analogRead(HALL_SENSOR_PIN);  

                    Serial.print("Button State: ");
                    Serial.println(buttonState);
                    
                    Serial.print("Hall Sensor Value: ");
                    Serial.println(hallValue);

                    if (buttonState == HIGH) {  
                        Serial.println("Button Pressed - LED ON");
                        digitalWrite(LED_PIN, HIGH);
                        delay(4000);  
                        digitalWrite(LED_PIN, LOW); 
                        Serial.println("LED OFF");
                        delay(300);
                    }

                    delay(200);
                }

        
      

The Hall sensor output changed when a magnet was brought near and the effect was displayed on the Serial Monitor in Arduino.