Change variable value at loop

Using Arduino Programming Questions
#1

Hello, I'm building a project using arduino, ws2812b led strips and hc05 bluetooth. The idea is to control the leds with different modes depending on the data received from a mobile phone.

I have two modes and a global variable that defines which mode is running, for example:

bool music = false;

void setup(){
   //setup
}

void loop() {
   someStuff();
   if(music){
      handleMusic();
   }else{
      if (miBT.available()){ 
          String r = miBT.readString();
          if(r.charAt(0) == 'M'){
             music = true;
          }else{
             handleOtherModes(r);
          }
      }
   }
}

The problem is when I set music = true, the code not works, it seems that is not entering the loop. However, if I remove that line, the code works correctly and the other modes work fine. Also if I set music = true at its definition, the music mode runs correctly.

I don't know if I'm forgetting something about setting global variables in loop or something. The code is a pseudocode, because the original is pretty long.

Thanks in advice.

#2

You need to put ; (semicolon) after function call. change handleMusic() to handleMusic();

#3

Try

bool music = false;

void setup() {
  //setup
}

void loop() {
  someStuff();
  if (music) {
    handleMusic();
  }
  // always look for cmds
  if (miBT.available()) {
    String r = miBT.readString();
    if (r.charAt(0) == 'M') {
      music = true;
    } else {
      setOtherModes(r); // just set the mod here
    }
  }
}
#4

@facugu

Please don't edit your opening post after comments are made. Reply #1 now does not seem to make sense.

Rather post the fixed code in a new reply.

#5

@facugu

What are the commands that you send? Just single letters? Maybe you're receiving a line ending as well ('\r' and/or '\n').

What are the mysterious functions? Do they block?

Once you are in music mode, you will never be able to change; @drmpf provided a solution for that.

Please be aware that neopixel libraries disable interrupts while updating the the strip. There is a good chance that you will loose Bluetooth data if you send more than one character at a time.

#6

I'm sending letters and a number, for example, if I send M5 is music, if I send M1 ... M4 are other modes, if I send Bx the brightness is set to x.

The thing is that I used an existing project that controls M1 to M4 modes, using classes and functions with classes, and I wanted to add a music reactive project, so I mixed them.

When I change in the code the value of the "music" variable to true or false, all the modes work correctly. But when I try to change it at the loop, at else section, it doesn't enter the loop, or look like that.

I changed the code based on @drmpf solution, but I still have the same problem.

Edit. I can share the code if you want, but maybe is a bit messy.

#7

Edit. I can share the code if you want, but maybe is a bit messy.

That sounds like a good idea ;)

#8

Well, I actually have to refactor lot of things because I’ve been updating it. I attached the code files.

Nodes.h (9.78 KB)

mixed.ino (11.2 KB)

#9

A quick look at the mixed.ino shows you still have

  if (music) {
    ...
  } else {
    if (miBT.available()) {      // si hay informacion disponible desde modulo
  ...

So if music is true, miBT.available() does not get called. which may be some of you problem

#10

Yes, maybe I undone that change in some moment. However when I changed according to your solution it still worked incorrectly.

I think the problem is not there because I'm trying to go from "Other mode" to "Music mode" and not reversed.

Thanks!