What I wanted to learn, and why it interested me: I've always wondered what to do if I run out of pins on a single Arduino. Turns out I can use two Arduinos. This tech brings me peace of mind.

Process and reflection: 

Although the process seemed initially straightforward, I ran into a lot of trouble this week. To start with, I completely forgot about the interference of tx/rx pins with uploading code, which led to much consternation before I asked for help. The initial coding didn't go much better either. For some reason, running two delays independently in the two Arduinos might have conflicted with each other, causing the light to flash. Also, not having ".show()" in the loop caused issues such as the light turning off, which was completely unexpected. I had to review my old code to see what could be the problem. However, using HSV was pretty straightforward and took some light googling.

As compared to my last domain-specific skill building, I believe this one was harder for me to accomplish. Both weeks were pretty rough in terms of workload and club commitments, and I wish I could've done a bit more, such as transmitting two inputs. I also wonder if I can connect 5V to the other Arduino's Vin directly, saving the 5V pin for the breadboard.

/*

 * Simple serial transmit counter

 */

const int POTPIN = A3;

int potVal;

void setup() {

  Serial.begin(9600);

  pinMode(POTPIN, INPUT);

}

void loop() {

  potVal = analogRead(POTPIN);

  Serial.println(potVal);

  delay(10);

}

/*

   Simple serial receiver

   Changes LED color based on received input.

*/

#include <Servo.h>

#include <Adafruit_NeoPixel.h>

#define PIN            8 // Digital pin the NeoPixel data line is connected to

#define NUM_LEDS       1 // The number of NeoPixels in your strip or ring

const int LEDPIN = 13;

Adafruit_NeoPixel strip = Adafruit_NeoPixel(NUM_LEDS, PIN, NEO_GRB + NEO_KHZ800);

int lightPos = 0;

void setup() {

  pinMode(LEDPIN, OUTPUT);

  strip.begin();

  strip.setBrightness(50);

  strip.show();

  Serial.begin(9600);

}

void loop() {

  strip.show();

  // when there is serial data waiting to be read

  if (Serial.available()) {

    lightPos = map(Serial.parseInt(), 0, 1023, 0, 65535);

    Serial.println(lightPos);

    delay(10);

  }

  strip.setPixelColor(0, strip.ColorHSV(lightPos, 255, 255));  

}