Arduino - Simulate multiple, out of sync, Incandescent bulb like flashing

Mark: Good work!

There are lots of ways to get the LEDs to be out of sync. You might want to look over the "random" number generating functions (found here). Using these along with "millis" should give you a fairly decent range of values to work with.

You may have seen this Arduino Lesson on the forum. It's all about blinking LEDs with PWM. Code is included.

I wanted three flashing lights on a bridge that were not in sync.

I described the desired results that I wanted and let ChatGPT generate the Arduino Sketch.

================== Input to ChatGPT =====================

create an Arduino sketch
comment THREE FLASHING LIGHTS ver 1.0
comment Lights not to be in sync
comment David Nissen  Nov 6,2023
comment This sketch generated by ChatGPT

three outputs on pins 8, 10, 12, lt1, lt2, lt3
all outputs to have a 50 percent dute cycle
the period for lt1 to be 2.00 sec
the period for lt2 to be 1.93 sec
the period for lt3 to be 1.84 sec

==================== Output from ChatGPT =================

Here's an Arduino sketch that implements the three flashing lights as per your requirements:

// THREE FLASHING LIGHTS ver 1.0
// Lights not in sync
// David Nissen Nov 6, 2023
// This sketch generated by ChatGPT

// Define the pins for the three lights
const int lt1Pin = 8;
const int lt2Pin = 10;
const int lt3Pin = 12;

// Define the periods for each light in milliseconds
const unsigned long lt1Period = 2000;  // 2.00 seconds
const unsigned long lt2Period = 1930;  // 1.93 seconds
const unsigned long lt3Period = 1840;  // 1.84 seconds

// Variables to keep track of the last state change time for each light
unsigned long lt1LastChangeTime = 0;
unsigned long lt2LastChangeTime = 0;
unsigned long lt3LastChangeTime = 0;

// Variables to keep track of the current state of each light
int lt1State = LOW;
int lt2State = LOW;
int lt3State = LOW;

void setup() {
  // Initialize the pins as outputs
  pinMode(lt1Pin, OUTPUT);
  pinMode(lt2Pin, OUTPUT);
  pinMode(lt3Pin, OUTPUT);
}

void loop() {
  // Get the current time
  unsigned long currentTime = millis();

  // Check if it's time to change the state of lt1
  if (currentTime - lt1LastChangeTime >= lt1Period / 2) {
    lt1State = !lt1State;  // Toggle the state
    digitalWrite(lt1Pin, lt1State);  // Update the LED
    lt1LastChangeTime = currentTime;  // Update the last change time
  }

  // Check if it's time to change the state of lt2
  if (currentTime - lt2LastChangeTime >= lt2Period / 2) {
    lt2State = !lt2State;  // Toggle the state
    digitalWrite(lt2Pin, lt2State);  // Update the LED
    lt2LastChangeTime = currentTime;  // Update the last change time
  }

  // Check if it's time to change the state of lt3
  if (currentTime - lt3LastChangeTime >= lt3Period / 2) {
    lt3State = !lt3State;  // Toggle the state
    digitalWrite(lt3Pin, lt3State);  // Update the LED
    lt3LastChangeTime = currentTime;  // Update the last change time
  }
}

This sketch will make three LEDs connected to pins 8, 10, and 12 flash with a 50% duty cycle, and their periods will be as specified. The lights are not in sync, as requested.

================ Load the Sketch into the Arduino IDE ============

Verify and then upload

========================== Result =======================

@MED posted:

I wanted to use multiple LEDs to simulate water level warning lights around Lionel swing bridge . . .

Thanks for posting.  Could you post a video of your prototype?  I would love to see your code in action.

Bob

That's pretty slick, I wonder if I could describe an application and have it code it for a Microchip PIC processor?   It would save me a lot of time.

gunrunnerjohn:

I am working on another project using ChatGPT to generate Arduino code. I have posted this on another thread.

https://ogrforum.com/...ch-for-train-control

I have also tested ChatGPT writing Python code with good results. I think it would be worthwhile for you to try writing code for a Microchip PIC processor.

I had previously done a project with the out of sync flashing lights and spent many hours writing and debugging code. The example posted here from beginning to end including testing took about one half hour.

It's certainly an interesting idea.

@RRDOC Three videos. First just a couple seconds after power on. Second about 25 seconds after the first completed. Third about 50 seconds after end of second video.

@MED posted:

@RRDOC Three videos. First just a couple seconds after power on. Second about 25 seconds after the first completed. Third about 50 seconds after end of second video.

bridges: the lights around the bridge do not flash the “fender” lights are a steady red. The lights on top of a bridge “range lights” Flash.

the fender is the center part around the bridge that protects it from boat traffic, also the side fenders on the or near the shoreline are marked as well solid red only. Center of channel hanging off the center of the bridge if too low for boat traffic will also be red. When the bridge swings open the center channel light will now be over the fender and a green light over red will show. On a lift span the light will show green when the bridge is fully raised and locked in the open position.

@MED

That is a great effect.  The effort to do the ramp up/ramp down and randomization really pays off.  Nice work!

Bob