Trouble Shoot Code For “Left Button” is not Working on Arduino Mini Powered PCB

First Time Poster Here:

I have an Arduino Pro Mini mounted to a PCB. The PCB with Arduino Pro Mini powers 4 LED’s There are also two smaller PCB’s that have 1 LED on them. so it is connected like. --- --- . The LED’s blink in a specific pattern when each button is pressed. I can get the right side to work but not the left.

I have posted the code below:

const int btn_left = 3;
const int btn_right = 2;
const int LEDs_L = 11;
const int LEDs_R = 10;
const int LEDs_BL = 13;
const int LEDs_BR = 12;
int Flag_R=0;
int Flag_L=0;
int Flag_BR=0;
int Flag_BL=0;
int interval=125;
int intervalB=100;
int Delay=6000;
int ledStateR = HIGH;
int ledStateL = HIGH;
int ledStateBR = HIGH;
int ledStateBL = HIGH;

unsigned long current_millis;
unsigned long prev_millis_R;
unsigned long prev_millis_r;
unsigned long prev_millis_br;
unsigned long prev_millis_L;
unsigned long prev_millis_l;
unsigned long prev_millis_bl;

void setup()
// initialize the LED pins as an output:
pinMode(LEDs_L, OUTPUT);
pinMode(LEDs_R, OUTPUT);
pinMode(LEDs_BL, OUTPUT);
pinMode(LEDs_BR, OUTPUT);

// initialize the pushbutton pin as an input:
pinMode(btn_left, INPUT);
pinMode(btn_right, INPUT);

void loop()
current_millis= millis();
if ( Flag_R==0 && Flag_L==0 && Flag_BR==0 && Flag_BL==0 )
digitalWrite(LEDs_L, HIGH);
digitalWrite(LEDs_R, HIGH);
digitalWrite(LEDs_BL, HIGH);
digitalWrite(LEDs_BR, HIGH);
if ( digitalRead(btn_right) == HIGH)
{ Flag_R=1;
prev_millis_R= current_millis;
prev_millis_r= current_millis;
prev_millis_br= current_millis;
if (digitalRead(btn_left) == HIGH )
{ Flag_L=1;
prev_millis_L= current_millis;
prev_millis_l= current_millis;
prev_millis_bl= current_millis;

if (current_millis - prev_millis_R <= Delay && Flag_R==1)
if (current_millis - prev_millis_r >= interval)
prev_millis_r = current_millis;
if (ledStateR == LOW) {
ledStateR = HIGH;
} else {
ledStateR = LOW;
digitalWrite(LEDs_R, ledStateR);

if (current_millis - prev_millis_br >= intervalB)
prev_millis_br = current_millis;
if (ledStateBR == LOW) {
ledStateBR = HIGH;
} else {
ledStateBR = LOW;
digitalWrite(LEDs_BR, ledStateBR); }


if (current_millis - prev_millis_L <= Delay && Flag_L==1 )
if (current_millis - prev_millis_bl >= interval)
prev_millis_bl = current_millis;
if (ledStateL == LOW) {
ledStateL = HIGH;
} else {
ledStateL = LOW;
digitalWrite(LEDs_L, ledStateL);

if (current_millis - prev_millis_l >= intervalB)
prev_millis_l = current_millis;
if (ledStateBL == LOW) {
ledStateBL = HIGH;
} else {
ledStateBL = LOW;
digitalWrite(LEDs_BL, ledStateBL);



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Thank you.

What is the pattern you are trying to create? Is it just toggling on/off at the interval rate? Also what does BL and BR stand for with the LEDs? I'm guessing Blue Left and Blue Right?

Will the left and right sides only be active one at a time, or could both sides have patterns running together?

Can you please post a circuit diagram of you project, including power supply?
Can you please post an Exported image of your PCB pattern in jpg please?

Thanks.. Tom... :smiley: :+1: :coffee: :australia: