yuhan21

Nov 28, 20225 min read

Blog Entry 3: Arduino Programming

Updated: Dec 3, 2022

Hello everyone! Welcome to my third blog entry! In this blog entry, I will be documenting my experience in Arduino Programming, where I experimented with input and output devices to facilitate different purposes. A blog overview is provided below:

There are 4 tasks that will be explained in this blog:

1) Input devices:

a. Interface a potentiometer analog input to maker UNO board and measure/show its signal in serial monitor Arduino IDE.

b. Interface a LDR to maker UNO board and measure/show its signal in serial monitor Arduino IDE

2) Output devices:

a. Interface 3 LEDs (Red, Yellow, Green) to maker UNO board and program it to perform something (fade or flash etc)

b. Include the pushbutton on the MakerUno board to start/stop part 2.a. above

3) For each of the tasks, I will describe:

1. The program/code that I have used and explanation of the code. The code is in writable format (not an image).

2. The sources/references that I used to write the code/program.

3. The problems I encountered and how I fixed them.

4. The evidence that the code/program worked in the form of video of the executed program/code.

4) I will describe:

My Learning reflection on the overall Arduino programming activities.

Input devices: Interface a potentiometer analog input to maker UNO board and measure/show its signal in serial monitor Arduino IDE.

1. Below are the code/program I have used and the explanation of the code.

Code/program in writeable format

Explanation of the code

int sensorPin = A0;

int ledPin = 13;

int sensorValue = 0;

void setup ()

{

pinMode (ledPin, OUTPUT);

}

void loop ()

{

sensorValue = analogRead (sensorPin);

digitalWrite (ledPin, HIGH);

delay (sensorValue);

digitalWrite (ledPin, LOW);

delay (sensorValue);

}

The sensorPin is initialized to be A0. The ledPin is initialized to be PIN 13. The sensorValue is initialised to be 0.

Under the void setup section,

pinMode (ledPin, OUTPUT) establishes PIN 13 as an output.

Under the void loop section lies the main code.

analogRead () was used to read the value of PIN A0.
The digitalWrite () command allows PIN 13 to turn ON or OFF depending on whether the signal sent is HIGH or LOW.
The delay (sensorValue) command allows the LED frequency to be changed as the knob of the potentiometer is turned.

2. Below are the hyperlink to the sources/references that I used to write the code/program.

https://splms.polite.edu.sg/d2l/le/enhancedSequenceViewer/172726?url=https%3A%2F%2Fb988e89b-eb2c-401a-999a-94b943da0008.sequences.api.brightspace.com%2F172726%2Factivity%2F5400368%3FfilterOnDatesAndDepth%3D1

(from ESP Brightspace)

3. Below are the problems I have encountered and how I fixed them.

Initially, my setup did not work out and I was very distressed, until I realised that I had placed the black wire on the positive terminal on the breadboard instead of the negative terminal.

Also, my LED did not light up during my first try. After asking for help from peers, I reaslied that the positive and negative terminals of my LED were swapped.

However, after swapping them, my LED was really dim. To try to solve this problem, I experimented with different resistors, and even using the resistor with the lowest resistance did not result in my led being brighter. However, after I redid the setup from scratch and with a different LED, it worked.

4. Below is the short video as the evidence that the code/program works.

Input devices: Interface a LDR to maker UNO board and measure/show its signal in serial monitor Arduino IDE:

1. Below are the code/program I have used and the explanation of the code.

Code/program in writeable format

Explanation of the code

int LDR = A0;

int ledPin = 13;

int LDRvalue = 0;

void setup ()

{

pinMode (ledPin, OUTPUT);

}

void loop ()

{

LDRvalue = analogRead (LDR);

if (LDRvalue > 950)

digitalWrite (ledPin, HIGH);

else

digitalWrite (ledPin, LOW);

}

PIN 13 is established as the LED pin and A0 is established as the LDR pin.

The LDRvalue is initialised to be 0.

Under the void setup section,

pinMode (ledPin, OUTPUT) establishes PIN 13 as the output.

Under the void loop section lies the main code.

analogRead (LDR) reads the value of the LDR pin.
When LDRvalue>950, the digitalWrite () command writes the LED to be turned ON. Otherwise, the LED will be turned OFF.

2. Below are the hyperlink to the sources/references that I used to write the code/program.

(from ESP Brightspace)

3. Below are the problems I have encountered and how I fixed them.

During my first attempt, I had forgotten to prove that when the LDR receives lesser light, L13 on the Arduino board will light up.

Hence, after analysing the code, I realised that LDRvalue > 600 is too low a value as the lighting in my environment gives a LDRvalue of around 900 and above, causing L13 on the arduino board to light up all the time, even when I did not cover the sensor. Hence, I made adjustments to the code and changed the LDRvalue to be > 950 instead. This then allowed L13 to not light up under normal lighting conditions and light up when i cover the sensor to decrease the light the LDR senses.

4. Below is the short video as the evidence that the code/program works.

Output devices: Interface 3 LEDs (Red, Yellow, Green) to maker UNO board and program it to perform something (fade or flash etc)

1. Below are the code/program I have used and the explanation of the code.

Code/program in writeable format

Explanation of the code

int animationSpeed = 0;

void setup ()

{

pinMode (13, OUTPUT);

pinMode (12, OUTPUT);

pinMode (11, OUTPUT);

}

void loop ()

{

animationSpeed = 400;

digitalWrite (13, HIGH);