RGB LED turns red after use [SOLVED]

veronica.hayes · June 6, 2017, 7:26pm

I am not sure if this is a hardware issue or a coding issue at the moment.
Basically, my code is supposed to take a temperature each time I press a button and the RGB LED is supposed to change color depending on the temperature recorded.
The program works fine, however after the 3 second delay, instead of all pins returning to low, the red pin will go to high for three seconds, then return to low.
I am currently using an Arduino UNO with a breadboard. I have pin 9 assigned to the red pin, pin 10 assigned to the green pin, and pin 11 assigned to the blue pin. Pin 2 is associated with my button and my temperature probe is assigned to analog pin 0. The whole thing is grounded and powered with 5V.
My program is included below.
Is this a hardware or software issue?

const int RED_PIN = 9;
const int GREEN_PIN = 10;
const int BLUE_PIN = 11;
int DISPLAY_TIME = 3000;

const int temperaturePin = 0;
const int button1Pin = 2; 
void setup()
{
 pinMode(RED_PIN, OUTPUT);
 pinMode(GREEN_PIN, OUTPUT);
 pinMode(BLUE_PIN, OUTPUT);
}


void loop()
{
  colorCode();
  pinMode(button1Pin, INPUT);
  Serial.begin(9600);
  pinMode(RED_PIN, OUTPUT);
  pinMode(GREEN_PIN, OUTPUT);
  pinMode(BLUE_PIN, OUTPUT);
}

void colorCode()
{
 int button1State;
  button1State = digitalRead(button1Pin);

if(button1State == HIGH)
 return (analogRead(temperaturePin) * 0.004882814);
  
  float voltage, degreesC, degreesF, degreesK;
  voltage = (analogRead(temperaturePin) * 0.004882814);
  degreesC = (voltage - 0.5) * 100.0;
  degreesF = degreesC * (9.0/5.0) + 32.0;
  degreesK = degreesC + 273.15;
  
  Serial.print("volt: ");
  Serial.print(voltage);
  Serial.print("  deg C: ");
  Serial.print(degreesC);
  Serial.print("  deg F: ");
  Serial.print(degreesF);
  Serial.print(" deg K: ");
  Serial.println(degreesK);
  
if(degreesF <= 70 & degreesF >= 60 )
{ 
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, HIGH);
  digitalWrite(GREEN_PIN, HIGH);
  delay(3000);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
}
else if(degreesF > 70 & degreesF <= 73)
  {
     digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, HIGH);
  digitalWrite(GREEN_PIN, LOW);
  delay(3000);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW); 
  }
else if(degreesF > 73 & degreesF <= 76)
  {
   digitalWrite(RED_PIN, HIGH);
  digitalWrite(BLUE_PIN, HIGH);
  digitalWrite(GREEN_PIN, LOW);
  delay(3000);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
  }
else if(degreesF > 76 & degreesF <= 79);
{
    digitalWrite(RED_PIN, HIGH);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
  delay(3000);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
}
}

Both the schematic and the Fritzing are now attached.

Solution:
The issue was that the code was defaulting the final 'else if' function as a default. Adding a default 'else' program solved the problem.

const int RED_PIN = 9;
const int GREEN_PIN = 10;
const int BLUE_PIN = 11;

const int temperaturePin = 0;
const int button1Pin = 2; 
void setup()
{
 pinMode(RED_PIN, OUTPUT);
 pinMode(GREEN_PIN, OUTPUT);
 pinMode(BLUE_PIN, OUTPUT);
   pinMode(button1Pin, INPUT);
  Serial.begin(9600);
  pinMode(RED_PIN, OUTPUT);
  pinMode(GREEN_PIN, OUTPUT);
  pinMode(BLUE_PIN, OUTPUT);
}

void loop()
{
  colorCode();
}

void colorCode()
{
 int button1State;
  button1State = digitalRead(button1Pin);

if(button1State == HIGH)
 (analogRead(temperaturePin) * 0.004882814);
  
  float voltage, degreesC, degreesF, degreesK;
  voltage = (analogRead(temperaturePin) * 0.004882814);
  degreesC = (voltage - 0.5) * 100.0;
  degreesF = degreesC * (9.0/5.0) + 32.0;
  degreesK = degreesC + 273.15;
  
  Serial.print("volt: ");
  Serial.print(voltage);
  Serial.print("  deg C: ");
  Serial.print(degreesC);
  Serial.print("  deg F: ");
  Serial.print(degreesF);
  Serial.print(" deg K: ");
  Serial.println(degreesK);
  
if(degreesF <= 70 & degreesF >= 60 )
{ 
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, HIGH);
  digitalWrite(GREEN_PIN, HIGH);
  delay(3000);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
}
else if(degreesF > 70 & degreesF <= 73)
  {
     digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, HIGH);
  digitalWrite(GREEN_PIN, LOW);
  delay(3000);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW); 
  }
else if(degreesF > 73 & degreesF <= 76)
  {
   digitalWrite(RED_PIN, HIGH);
  digitalWrite(BLUE_PIN, HIGH);
  digitalWrite(GREEN_PIN, LOW);
  delay(3000);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
  }
else if(degreesF > 76 & degreesF <= 79)
  {
    digitalWrite(RED_PIN, HIGH);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
  delay(3000);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
  }
else
{
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
}
}

PaulRB · June 6, 2017, 7:43pm

veronica.hayes:
The program works fine

Are you sure? That code you just posted, or did you modify it later. I can't see how that code lights any leds at all.

Please post a schematic. Hand-drawn is OK.

veronica.hayes · June 6, 2017, 8:58pm

Here is the schematic

IamFof · June 6, 2017, 9:25pm

Please don't use Fritzing to show your circuit.

Just post a hand drawn diagram.

veronica.hayes · June 7, 2017, 12:37pm

If not a return, what do you recommend I use? I copied and pasted that part from a sample circuit that came with my board actually....
I moved the other thing into setup, but it is giving me the same red light after its coded light.

veronica.hayes · June 7, 2017, 1:47pm

I thought the return was needed to output a line into the Serial Monitor because it was within an if statement, despite the fact that it was in a loop.
Basically, I am using that line to tell the program what to output on the serial monitor when I hit a button.
That has always worked. The issue comes with the following if....else if function, where given an output on the serial monitor, being temperature in degrees Fahrenheit, it should output a color given the temperature. This part works.(A switch case would in theory work here too, but this is my third code ever so I didn't want to try that quite yet.)
The issue is that when I run the function, it outputs the correct color before the delay but after the delay, instead of turning off immediately, the RGB turns red before turning off.

Now I guess what could be happening is one of two things;

the last portion of my else if function calls for red. Typically, the else if function will stop when it hits a true statement. Is something in my code preventing this from occurring, or am I just using this function wrong.
maybe it is doing a slow voltage switch because the red is a lower voltage compared to the other two? Not too sure on this one but my point is, is it an issue with my RGB pin itself?

veronica.hayes · June 7, 2017, 3:32pm

Delta_G:
To output to serial monitor use Serial.print

But if I do that, won't it take temperatures every few seconds as a continuous loop? I just want one read per button press....

Anyways, while doing a continuous read of the temperature (which is fairly consistent in the range yielding purple) the issue is still appearing. During the scan time, the purple light will correctly appear for 3 seconds, but before the next scan is taken, the light turns red for three seconds.
Maybe I just need to change the delay.

veronica.hayes · June 7, 2017, 3:44pm

Delta_G:
I think you need some basic C++ tutorials.

I know I do actually--this was me extending the tutorial I was doing.
Anyways, I solved it by adding an additional 'else' function.
No idea why it was happening.

const int RED_PIN = 9;
const int GREEN_PIN = 10;
const int BLUE_PIN = 11;

const int temperaturePin = 0;
const int button1Pin = 2; 
void setup()
{
 pinMode(RED_PIN, OUTPUT);
 pinMode(GREEN_PIN, OUTPUT);
 pinMode(BLUE_PIN, OUTPUT);
   pinMode(button1Pin, INPUT);
  Serial.begin(9600);
  pinMode(RED_PIN, OUTPUT);
  pinMode(GREEN_PIN, OUTPUT);
  pinMode(BLUE_PIN, OUTPUT);
}

void loop()
{
  colorCode();
}

void colorCode()
{
 int button1State;
  button1State = digitalRead(button1Pin);

if(button1State == HIGH)
 (analogRead(temperaturePin) * 0.004882814);
  
  float voltage, degreesC, degreesF, degreesK;
  voltage = (analogRead(temperaturePin) * 0.004882814);
  degreesC = (voltage - 0.5) * 100.0;
  degreesF = degreesC * (9.0/5.0) + 32.0;
  degreesK = degreesC + 273.15;
  
  Serial.print("volt: ");
  Serial.print(voltage);
  Serial.print("  deg C: ");
  Serial.print(degreesC);
  Serial.print("  deg F: ");
  Serial.print(degreesF);
  Serial.print(" deg K: ");
  Serial.println(degreesK);
  
if(degreesF <= 70 & degreesF >= 60 )
{ 
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, HIGH);
  digitalWrite(GREEN_PIN, HIGH);
  delay(3000);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
}
else if(degreesF > 70 & degreesF <= 73)
  {
     digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, HIGH);
  digitalWrite(GREEN_PIN, LOW);
  delay(3000);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW); 
  }
else if(degreesF > 73 & degreesF <= 76)
  {
   digitalWrite(RED_PIN, HIGH);
  digitalWrite(BLUE_PIN, HIGH);
  digitalWrite(GREEN_PIN, LOW);
  delay(3000);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
  }
else if(degreesF > 76 & degreesF <= 79)
  {
    digitalWrite(RED_PIN, HIGH);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
  delay(3000);
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
  }
else
{
  digitalWrite(RED_PIN, LOW);
  digitalWrite(BLUE_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
}
}

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RGB LED turns red after use [SOLVED]

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