Basic RGB code LOGIC

Using Arduino Programming Questions
1

Please explain what this logic does to fade out the color... the math of it...


for(int i = 0; i < 255; i += 1) // fades out red bring green full when i=255
2

That logic does nothing to fade anything.

It is part of a for loop, which you should learn all about:

By some strange twist of fate, that site uses dimming an LED in one of the examples.

a7

3

If one of the legs of the RGBLED is on a PWM pin, and the value of "i" is applied to that pin, that color (or all colors if the pin is on the common pin) would "fade" in or out.

This diagram shows the PWM duty cycle lengthens as "i" increases, keeping the color "ON" longer

Here is an example (find the "fade" function):

4

break down the logic behind this code snippet that aims to create a fading effect from red to green:

for (int i = 0; i < 255; i += 1) {
    redValue -= 1;
    greenValue += 1;
    analogWrite(RED, redValue);
    analogWrite(GREEN, greenValue);
    delay(delayTime);
}
  1. Initialization:
  • We start with redValue set to 255 (full intensity red) and greenValue set to 0 (no green).
  • The loop variable i ranges from 0 to 254 (255 iterations).
  1. Fading Red to Green:
  • As i increases, we decrement redValue by 1 and increment greenValue by 1.
  • This gradual reduction in redValue and increase in greenValue results in a smooth transition from red to green.
  • The analogWrite() function is used to control the intensity of the red and green LEDs (assuming an RGB LED setup).
  • The delay(delayTime) ensures a gradual fade over time.
  1. Math Behind the Fading:
  • Initially, redValue is 255, and greenValue is 0.
  • As i increases, redValue decreases, and greenValue increases proportionally.
  • When i reaches 255, redValue becomes 0 (no red) and greenValue becomes 255 (full green).

In summary, this loop gradually decreases the red component while increasing the green component, resulting in a fade-out effect from red to green. The math involves linearly adjusting the intensity values to achieve the desired transition.

6

No posted one and my post was relocated my staff :face_with_monocle:

7

Yes. Sorry.

Are you adding RGBLED or WS2812B to your kit car?

8

I’m adding Mega 2560 should me in mail tomorrow right now I’m working on the code and different libraries I’ve retired my Galileo gen 2 :face_with_raised_eyebrow:

9

mis spell be in the mail.

10

I appreciate your explanation. Will this explain why I see the led changing in a range of colors? The decremental change in one color value and the simultaneous increase in another color value results in the LED color changing by blending color values as the first value goes to 0 and the second reaches its highest value 255?

11

Gpt chat does code also check it out. :slightly_smiling_face:

12

No, it does not.

13

It can write poetry. It can to.:slightly_smiling_face:

14

Your code seems to be controlling two motors (Channel A and Channel B) to move in different directions. Let’s break it down:

  1. In the setup() function:
  • You’ve set up the pins for Channel A (pins 12 and 9) and Channel B (pins 13 and 8).
  • Channel A controls one motor, and Channel B controls another.
  1. In the loop() function:
  • You’re alternating between forward and backward motion for both motors.
  • Here’s a summary of what happens:
    • Motor B moves backward at half speed.
    • Motor A moves forward at full speed.
    • After a delay of 500 milliseconds:
      • The brakes are engaged for both motors.
    • Motor B moves forward at full speed.
    • Motor A moves backward at full speed.
    • After another delay of 500 milliseconds:
      • The brakes are engaged again.

However, there are a couple of issues in your code:

  • You’re using analogWrite on pins 11 and 3, but these pins are not defined in your setup.
  • You’re missing the pinMode setup for pins 11 and 3.

To move forward in one direction, you can simplify your code. Assuming you want both motors to move forward, you can do something like this:

void setup() {
  pinMode(12, OUTPUT); // Motor A
  pinMode(13, OUTPUT); // Motor B
}

void loop() {
  digitalWrite(12, HIGH); // Motor A forward
  digitalWrite(13, HIGH); // Motor B forward
  delay(1000); // Move forward for 1 second
  digitalWrite(12, LOW); // Stop Motor A
  digitalWrite(13, LOW); // Stop Motor B
  delay(1000); // Pause for 1 second
}

Feel free to adjust the delay times and motor speeds according to your requirements

15

You can leave the ChatGPT out of it. It can't write code... or analyze it.

It also neglected to enable the channels.

16

:slightly_smiling_face: Motor with Motor Shield Rev3 Mega 2560 for tracked drone car.

Ok I have it working now I removed the part of the sketch I didn’t need was trying to see if others that use the shield for their projects and was trying to understand what’s going on with the code. Ok I have one movement a tracked robot an I’m adding the Mega 2560 so I can put in a lot can functions. It takes six individual movement sketches to be joined into code to have complete maneuverability of the tracked robot. It has to spin to the left and right that’s yaw/ move forward and backwards break left and right. At the same time was trying to learn how your chat rooms work. I’ve never used it before and wonted to create a simple topic. My wifi board is on its way so I will have my serial plotter working.
Does this look ok?
RV3 Farward

void setup() {

//Setup Channel B
pinMode(13, OUTPUT); //Initiates Motor Channel B pin CW Direction

//Setup Channel A
pinMode(12, OUTPUT); //Initiates Motor Channel A pin CCW Direction

}

void loop(){

//Motor B forward @ half speed
digitalWrite(13, HIGH); //Establishes forward direction of Drone Channel B

analogWrite(11, 255); //Spins the motor on Channel A at full speed

//Motor A forward @ full speed
digitalWrite(12, LOW); //Establishes forward direction of Drone Channel A

analogWrite(3, 255); //Spins the motor on Channel A at full speed

}

17

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