Help with RGB Strip Code

Projects Programming
1

Hello,
I have written a code to control a set of RGB LEDs and I am looking for a way to clean up my code to be easier to read.
As you can see below, I have programmed my RGB strip to pulse along the entire strip, and when it goes along the previous led will be dimmer (until I get to -4 LED). This gives the effect of organic flow but can this be reduced into a string for ease if I want to expand the LEDs in flow.

I hope you can help guys. I will answer any questions

void Pulse(){
ledsUPPER[ledPos].setRGB(255, 0, 0); //set LED on and colour for Pos, this sets the main colour in both directions
if (dir == 0) { //If the LED is equal to Zero
if (ledPos > 0) ledsUPPER[ledPos-1].setRGB(150, 0, 0); //if forward LEDs are above 0, set 2nd one this colour
if (ledPos-1 > 0) ledsUPPER[ledPos-2].setRGB(75,0,0); //if forward LEDs-1 are above 0, set 3rd one this colour
if (ledPos-2 > 0) ledsUPPER[ledPos-3].setRGB(50, 0, 0); //if forward LEDs-2 are above 0, set 4th one this colour
if (ledPos-3 > 0) ledsUPPER[ledPos-4].setRGB(10,0,0); //if forward LEDs-3 are above 0, set 5th one this colour
}

2

but can this be reduced into a string

What do you mean by this? A string is a NULL terminated array of chars, so the question makes no sense.

3

Sorry, I meant array but I maybe wrong on that too. I'm really looking for a way of reducing the lines of code, which seem unnecessary.

4

I'm really looking for a way of reducing the lines of code, which seem unnecessary.

Look at the lines of code. Do you see any patterns? Like the if statement compares ledPos - i, where i is 0 to 4. Like the index is ledPos - i - 1, where i is 0 to 4.

If the values to assign to the LED at some position were in an array, you'd need one statement and a for loop.

5

forgive me, I'm new to this.

So do I need to create an array for ledPos? Also how would i take into account the luminosity of the led?

I appreciate the help

David

6

So do I need to create an array for ledPos?

No. You need an array for the red values to use in the call to Pulse(). You need an array for the green values. And, you need an array for the blue values.

7

Thanks Paul,

could you show me an example, and I can work on it from there

8

DavidMason:
Thanks Paul,

could you show me an example, and I can work on it from there

    byte reds[4] = { 150, 75, 50, 10 };
    byte grns[4] = { 0, 0, 0, 0 };
    byte blus[4] = { 0, 0, 0, 0 };

    for(byte i=0; i<4; i++)
    {
        if(ledPos - i > 0) ledsUPPER[ledPos -i - 1].setRGB(reds[i], grns[i], blus[i]); 
    }
9

Thank you Paul,

Much appreciated

David

10

Hi Mark,

I was wondering if you could explain how the line of code works below? I'm trying to understand the -1 and how it works, also why -i?

 if(ledPos - i > 0) ledsUPPER[ledPos -i - 1].setRGB(reds[i], grns[i], blus[i]);

Many thanks

11

I'm trying to understand the -1 and how it works, also why -i?

Create a table. List the values of i down the page. Across the page, have the headings ledPos - n, ledsUPPER[n], reds[n], blus[n], and grns[n]. For each cell, calculate the value of n based on the value of i. Then, write the value of the appropriate array in the cell.

For instance, when i is 0, ledPos - 0 is ledPos. When i is 1, the value being tested is ledPos - 1.

The ledsUPPER index values will be ledPos -1 and ledPos - 2.

The index values for reds, grns, and blus will be 0 and 1.

Compare the index values and/or array values at the index position to the code that you supplied.