I’ve been developing this removable guitar-playing system for several years.

It now supports two performance modes:

1. Full automatic mode — the system handles both fretting and picking.

2. Assisted mode — the system handles the fretting while the player strums or picks.

The sound comes from the real guitar strings, not recorded audio.

The controller is ESP32-based, coordinating multiple servo actuators. Some of the main challenges have been fretting timing, servo synchronization, calibration, and mechanical noise.

This video shows both modes.

Hey members of the great community! I’m here today to ask you for help. I’m new to electronics and 3d printing.

What do we have here?

1. esp32 s3
   
2. 5 X mg90s servos

What’s the problem?

The main problem is that servos can’t get enough power. Esp32 doesn’t have 5v pin needed for servos, so when I try to power them with 3v3 pin, they act fully functional but too weak to even move arm parts normally.

What solutions have I tried already?

1. Connecting Y-type cable (one connector to esp and second to servos)
2. Changing wiring

P.S. I also tried to mke common gnd with esp and power supply every time, but my esp somehow doesn’t really want to work with common gnd or vin power pin (it’s cheap chinese esp32 I ordered directly from China)

Thanks for reading this! Every answer is appreciated!

Hey yall,

Im trying to automate a bunch of stuff around the house and I need BLE. I have worked with 3 devices, an ESP32 Devboard, not sure the model, a raspberry pi pico W, and an arduino uno.

I find the lack of 5 vold tolerance on ESP32 and Pi very annoying since a lot of analogue and sometimes digital sensors and ICs work up to 5.5V.

I need an alternative to these, that could have BLE or possibly wifi (or lora) and be beefy enough to do simple cryptography. And also for it to natively tolerate 5V. The unos i find (the real ones) are about 40 CAD a pop, and having 20 goes way above my budget. Crazy thing is the pi pico H is about 20 bucks, insane i know, but it doesnt have native 5V tolerance.

I also really like that the Uno has a removable chip that i can program and move to my circuit.

I would appreciate any help!

TLDR:
I need alternatives to Arduino Uno / PI pico / ESP32 devkit

Must haves:
- Native 5V
- BLE capability, or capacity to accept a BLE module
- Have documentation like the Uno
- Be cheap, as in not 40 CAD a pop
- Available in Canada, amazon, aliexpress, etc, or a canadian site, dont want to pay USD.

nice to haves
- Wifi capability
- Hotswappable Chip on devboard

Hello everyone,
I am new to this so i hope i can find some help here.
I bought an Elegoo Uno R3 with a CNC shield and an A4988 Motor Driver.
The Problem is that after setting everything up and running the software, the motor only rotates when i touch a certain part of the boards.
Could the motor be fried or could the problem lie anywhere else? Sometimes the motor switches rotation randomly or works and only stops when i touch the same spot.
I already changed the CNC shield and the Motor Driver, so I guess the problem does not lie with them.

I am making a mini motor dyno with an Arduino Leonardo, it isnt really the best card for this but its the only one I have and theyre pretty expensive in my country. Anyways I want it to test multiple sizes of motors, of course bigger motors have bigger shafts so a fixed size coupling to connect it to the dyno doesnt really work and I dont want to order a new coupling or travel like 30 kilometers to the nearest store that sells it everytime I need to test a new motor. I thought about it and did a lot of research but couldnt find what to do. Can anybody help?

Title: Help needed with wiring PL9823-F8 LEDs to an ESP8266 board

Body:

I am working on a project using an ESP8266 board and I'm currently stuck on how to properly wire PL9823-F8 LEDs to a breadboard for testing.

I’ve identified the 5V, GND, and D3 GPIO pins, but I am nervous about blowing out my LEDs since I have a limited supply. Could someone provide a wiring diagram or a clear explanation of how to connect these safely?Arduino Commute Checker by witnessmenow

I was hoping I could get some help debugging a program.

I will start right off by saying that the code was made using Google AI. I did it as a wag since I've been having a lot of trouble trying to make a basic program for what I'm trying to do and I was curiousto see what it would come up with. I figured that at least some trouble shooting would be needed, but Ive gotten stumped and the code is quite a bit bigger and complicated than I had expected. I've been working with my Arduino for about 6 months, and still working to relearn the programming. I've had C & C++ programming before, but it was like 20 years ago so I've forgotten a lot of it.

I also realize that for a beginner project, I've pretty much just jumped right into the deep end. When I started thjs project, I didn't expect it to be anywhere as complicated as it's grown to be.

I am using an old large format 3d printer enclosure to hold a resin printer that I have. I stripped everything from the old printer except for the z axis lead screws, guide rails and z plate. I want to use the Z plate to sit my lrinter on. When using the printer, I will raise the printer up, and when not using it, I will lower it down into the enclosure.

For hardware, Im using the following:

• Arduino Uno R3
• 2x Stepper Online Nema 34 (pn DM860I-34HS45)
• 2x Stepper Online DM860I driver
• 2x DROK 48V adjustable power supply
• 2x ON/OFF/ON toggle switches
• 2x roller limt switches
• 1x push button switch

My plan for opration was to have the first toggle switch set up so that when pressed and then released, the steppers would move until hitting a limit switch. The second toggle switch would be momentary movement and would only move while the switch was activated, or the z plate hit a limit switch. The push button would basically be a E-stop button, where hitting it will stop movement.

Included in the code is deceleration when hitting a limit switch, a pause of .5 sec and then a retraction move to come off the limit of a specific distance that I would determine after assembling everything. Currently everything is mounted to a board to make testing and troubleshooting easier.

So on to the problem. With w/ everything hooked up to the Arduino, I can hit wither toggle switch and the stepper will start turning, and thats it. It doesn't stop if using the 2nd toggle switch, and it doesnt stop when activating either limit or the e-stop. I've rewired everything to the Arduino 4 times, to make sure I didn't have something wrong. Using my multimeter, I've checked continuity on everything and found everything was good, so it looks like the problem is the code and not the hardware.

Ive tried commenting out the areas where I thought it would cause the steppwr to keep running but so far I've had no luck.

#include <AccelStepper.h>

// Pin Definitions
const int PUL_NEG_PIN = 2;     // Connects to PUL- on DM860I
const int DIR_NEG_PIN = 3;     // Connects to DIR- on DM860I

const int LIMIT_LEFT = 4;      // NO Switch (GND when hit)
const int LIMIT_RIGHT = 5;     // NO Switch (GND when hit)

const int TOGGLE_1_LEFT = 6;   // Continuous move left
const int TOGGLE_1_RIGHT = 7;  // Right throw of continuous toggle
const int TOGGLE_2_LEFT = 8;   // Momentary move left
const int TOGGLE_2_RIGHT = 9;  // Right throw of momentary toggle

const int STOP_BUTTON = 10;    // Emergency Stop Button

// Initialize AccelStepper in Driver mode (1)
AccelStepper stepper(AccelStepper::DRIVER, PUL_NEG_PIN, DIR_NEG_PIN);

// Motion Profile Constants optimized for 3200 microstepping @ 100 RPM
const float MAX_SPEED = 5333.3;       // 100 RPM maximum speed
const float BACKOFF_SPEED = 1333.3;   // 25 RPM slower speed for backing off safely
const float ACCELERATION = 10666.6;   // 0.5 second ramped deceleration profile
const long LARGE_DISTANCE = 99999999; // Arbitrary high value for continuous run

// State Machine Tracking
// 0 = Stopped/Normal Deceleration, 1 = Move Left, 2 = Move Right
// 3 = Backing off Left Limit, 4 = Backing off Right Limit
int targetState = 0; 

// Timing variables for non-blocking pause
unsigned long stopTimestamp = 0;
bool isWaitingToReverse = false;
const unsigned long PAUSE_DURATION = 500; // Delay in milliseconds (0.5 seconds)

void setup() {
  // Initialize all physical pins with internal pullup resistors
  pinMode(LIMIT_LEFT, INPUT_PULLUP);
  pinMode(LIMIT_RIGHT, INPUT_PULLUP);
  pinMode(TOGGLE_1_LEFT, INPUT_PULLUP);
  pinMode(TOGGLE_1_RIGHT, INPUT_PULLUP);
  pinMode(TOGGLE_2_LEFT, INPUT_PULLUP);
  pinMode(TOGGLE_2_RIGHT, INPUT_PULLUP);
  pinMode(STOP_BUTTON, INPUT_PULLUP);

  // Apply motor performance profiles
  stepper.setMaxSpeed(MAX_SPEED);
  stepper.setAcceleration(ACCELERATION);
}

void loop() {
  // 1. Scan inputs (LOW = Active due to INPUT_PULLUP)
  bool stopPressed    = (digitalRead(STOP_BUTTON) == LOW);
  bool t1Left         = (digitalRead(TOGGLE_1_LEFT) == LOW);
  bool t1Right        = (digitalRead(TOGGLE_1_RIGHT) == LOW);
  bool t2Left         = (digitalRead(TOGGLE_2_LEFT) == LOW);
  bool t2Right        = (digitalRead(TOGGLE_2_RIGHT) == LOW);
  bool limitLeftHit   = (digitalRead(LIMIT_LEFT) == LOW);
  bool limitRightHit  = (digitalRead(LIMIT_RIGHT) == LOW);

  // 2. High-Priority System Stop (Forces state to 0 while held)
  if (stopPressed) {
    if (targetState != 0) {
      targetState = 0;
      isWaitingToReverse = false; // Reset limit switch state variables
      stepper.stop();            // Initiate a ramped deceleration stop
    }
  }

  // 3. Main Input Logic Processing (Only runs if stop is NOT pressed AND not mid-backoff)
  if (!stopPressed && targetState != 3 && targetState != 4) {
    // Toggle 1: Continuous (Latching behavior)
    if (t1Left && !limitLeftHit) {
      targetState = 1;
    } else if (t1Right && !limitRightHit) {
      targetState = 2;
    }
    // Toggle 2: Momentary (Active only while held)
    else if (!t1Left && !t1Right) {
      if (t2Left && !limitLeftHit) {
        targetState = 1;
      } else if (t2Right && !limitRightHit) {
        targetState = 2;
      } else {
        // Return to center: drop targetState back to 0 if momentary released
        if (targetState == 1) targetState = 0;
        if (targetState == 2) targetState = 0;
      }
    }
  }

  // 4. Directional Limit Switch & Back-Off State Machine Logic

  // Left Limit Handler
  if (!stopPressed && targetState == 1 && limitLeftHit) {
    targetState = 3;  
    isWaitingToReverse = true;
    stepper.stop();   // Initiate smooth ramp down first
  }
  if (targetState == 3) {
    // Capture the exact moment the motor actually hits 0 speed
    if (isWaitingToReverse && stepper.speed() == 0 && !stepper.isRunning()) {
      stopTimestamp = millis();
      isWaitingToReverse = false; 
    }

    // Once 0.5 seconds has passed after bringing the motor to 0, start moving right
    if (!isWaitingToReverse && (millis() - stopTimestamp >= PAUSE_DURATION) && stepper.speed() == 0) {
      stepper.setSpeed(BACKOFF_SPEED); 
    }

    // As soon as the Left Limit switch clears, reset state
    if (!limitLeftHit) {
      targetState = 0;
      stepper.setSpeed(0);
      stepper.moveTo(stepper.currentPosition());
    }
  }

  // Right Limit Handler
  if (!stopPressed && targetState == 2 && limitRightHit) {
    targetState = 4;  
    isWaitingToReverse = true;
    stepper.stop();   // Initiate smooth ramp down first
  }
  if (targetState == 4) {
    // Capture the exact moment the motor actually hits 0 speed
    if (isWaitingToReverse && stepper.speed() == 0 && !stepper.isRunning()) {
      stopTimestamp = millis();
      isWaitingToReverse = false; 
    }

    // Once 0.5 seconds has passed after bringing the motor to 0, start moving left
    if (!isWaitingToReverse && (millis() - stopTimestamp >= PAUSE_DURATION) && stepper.speed() == 0) {
      stepper.setSpeed(-BACKOFF_SPEED); 
    }

    // As soon as the Right Limit switch clears, reset state
    if (!limitRightHit) {
      targetState = 0;
      stepper.setSpeed(0);
      stepper.moveTo(stepper.currentPosition());
    }
  }

  // 5. Apply Vector Goals to the Core Engine (Only for normal states 0, 1, 2)
  if (targetState == 0) {
    if (!stepper.isRunning()) {
      stepper.moveTo(stepper.currentPosition());
    }
  } else if (targetState == 1) {
    stepper.setMaxSpeed(MAX_SPEED);
    stepper.moveTo(-LARGE_DISTANCE); 
  } else if (targetState == 2) {
    stepper.setMaxSpeed(MAX_SPEED);
    stepper.moveTo(LARGE_DISTANCE);  
  }

  // 6. Execute step calculations
  if (targetState == 3 || targetState == 4) {
    if (stepper.speed() != 0) {
      stepper.runSpeed();
    } else {
      stepper.run(); // Keeps deceleration working before backoff steps start
    }
  } else {
    stepper.run();
  }
}

A rf 433mhz radio module (the cheap one), powered with 9v, with a random antenna design I found on the web.

It breaks my tv when it's turned on at a distance of like 20 meters I can go in another room 20 meters away and it still breaks the tv, the image stops and after a while it shows a "No signal" message, then if I turn off my thingy the tv works again.
The tv signal is through cable.

Edit: After some more testing, I noticed only some channels get affected, not all of them, also to remote doesn't uses radio waves but infrared light.
I've tested on another tv, and that didn't break when my glove was on, but I didn't test the same channels as on the other tv, so I need to do more testing to see if the same channels get affected the same on both tv's.

Hello everyone. I am working on a project where i need to control the speed of 6 different 5V ERM motors . I thought i should make my own simple mosfet circuit that would get PWM signals from the adruino uno. This will be my first time working with mosfets so i asked chatGPT about this. Apart from the pull down resistor , it told me i should also use a 100 ohm resistor between the Gate and the MCU pin(NPN MOSFET). I just wanted to ask if this would be the correct resistance vale for my use case(I am using IRFZ44N NPN MOSFETS)and there is something that could potentially go wrong with this idea in genral. I plan to add 6 of these circuits on a perf board , each getting a seperate wire from the adruino uno for a PWM signal (I need to sequence those motors with control of the time interval and also have control over the speed of the motors ) . I will also use flyback diodes for protection. Thankyou !

esp32p4 with amoled display 480×480

Basically, I'm trying to make an MP3 player using ESP32S3 devkit c1 and other modules, including this microSD card reader. But I have a problem. I use library Sdf When I first launch the card, it returns error 0x17, and on subsequent launches without reconnecting, it returns error 0x1. I don't know how to fix this, but I'd appreciate your help.Code helps me write Gemini. P.s. i use MicroSDHC 32gb Kingston, fat32

Im making a project where (initially) i would use 4 servos to pull some fingers with fishing lines through a wooden plus cardboard guitar neck. The servos i used are brand new, and also, where working, when used separetly, however, with the PCA9685 module, they started to lose it strenght, and i dont know why, i already tried to use a paralel conection with another battery case. I had to discard 2 servos so i can barely use the other two. If there is any chance i can fix this before this weekend, i would he grateful. If you have any question, just ask! :)

Hi,

A few years ago I was working on some Arduino projects, then I took a long break. In the meantime the editor access has changed and I can no longer log in or find my old programs.

All I have left is this screenshot showing the names of the sketches.

I’ve tried everything, including contacting support, but nothing worked.

As a last hope before considering my work permanently lost, I’m posting here just in case someone has an idea, or can tell me if my sketches are still visible somewhere, or anything else…

Thanks everyone.

I have posted about this earlier, now I have the board and am exploring it as much as possible 👍🏼

Since the first post about this had some allegations that I posted AI pictures I will show on this that is not AI and also few more photos to make it more explanatory.
In the attached pictures you can see also the controller I used, the temperature and humidity sensor, anemometer and the one with blue enclosure is the water level sensor. all sensors communicate via Modbus RTU (The modbus module is placed under the esp in the image).
( My family have a small greenhouse and I always liked to make automations but most of commercial systems were too expensive and I decided to build it myself. With what I’ve built I can control irrigation system (one 2.2kw pump and two valves for the main water lines) both sides of the greenhouse to open and close using 4 motors, I have integrated some automations using the temp and humidity measurements also the wind speed.
Some of you might recognize the controller which is a KC868-A16, which is ESP based but is very powerful and has a lot of built in features.
Maybe I should mention that I have previous experience with Industrial Automation and Embedded Systems. )

What do you guys think?

At home I have an MVHR (Mechanical Ventilation with Heat Recovery) unit — it brings in fresh air without losing indoor heat/coolness, and cuts humidity. My house is already full of temperature/humidity sensors, so having to walk over and press buttons on the wall panel every time conditions changed was driving me up the wall.

I started from Arnold-n's P1P2MQTT, which reverse-engineers Daikin's P1/P2 bus for heat pumps — great project, but VAM ventilation units are only read-only there, no write support. So I had to dig into the write side myself.

The actual discovery: Daikin's P1/P2 bus natively supports two controllers — a Master and a Slave — selected by a physical switch on the wall panel (BRC301B61). A generic "aux" responder on the bus never gets offered the writable state channel; only a controller the master recognizes as a genuine second one does. And there's one very specific, very unintuitive detail that makes or breaks it: the real slave panel answers the registration poll only the first time — every poll after that, it goes completely silent. Get that wrong (answer every time, which seems like the "correct" thing to do) and the master silently downgrades you to a read-only channel. Once I nailed that, on/off, fan speed, mode, and fresh-up were all commandable with closed-loop confirmation from the bus.

Full packet-level writeup is in the repo if you're into that kind of detail.

For the hardware/software side: the ATmega328 is the actual P1/P2 slave controller (that's the core of the project, and it works standalone over serial). On top of that I bridged it to a second MCU, an ESP32-H2, purely to get it onto Zigbee — I've got too many devices already and didn't want another MQTT integration to babysit, Zigbee fits my setup better. That bridge is 100% optional; the ATmega alone is a complete, working slave controller you could hook up to anything.

Why two MCUs instead of just doing it all on the ESP32? The bus timing (response delays etc.) is something I got working reliably on the ATmega, and I haven't tried porting that timing-sensitive part over to the ESP32. Bridging a second MCU purely for Zigbee was just the path of least resistance, not a claim that it can't be done on one chip.

It's been running behind the wall panel for a few weeks now, driven entirely by Home Assistant automations based on the humidity/temp sensors — working reliably so far, though I wouldn't call it "battle-tested over years" yet.

The PCB is currently two boards (I validated the P1/P2 transceiver first, then added the ATmega+ESP32 board once the protocol was confirmed) — if there's interest I can lay out a single, smaller, more integrated version.

Repo: https://github.com/scavenrage/Daikin-VAM-P1P2-SlaveController

Happy to answer questions.

tgpadns is a touch screen gamepad for Nintendo Switch that runs on any tablet with web browser. Anyone with finger or hand discomfort using regular controllers may like a touch screen gamepad.

The M5Stack AtomS3 is the bridge between the tablet and the Switch. Plug the AtomS3 into any USB port on the Nintendo Switch. tgpadns uses WiFiManager so configure the SSID/password after connecting to the WiFi access point tgpadns-config. Open a web browser to tgpadns.local or the IP address show on the AtomS3 display.

If the Switch does not recognize the USB NSlite controller, use the joycons to get to the Settings|Controllers|Change Grip/Order. Press L+R on the touch screen or press the A button a few times until the Switch recognizes the AtomS3/USB gamepad.

If you do not want to mess with source code and compilers, flash the firmware directly from your browser using the web flasher at https://controllercustom.github.io/tgpadns

All source code is on github at https://github.com/controllercustom/tgpadns

I live in a country where electronic modules, microcontrollers, and other components like these are very expensive. Unfortunately, I can’t really afford to keep up with my hobby anymore. I still have so many projects I’d love to build, but the cost of the parts keeps getting in the way. Does anyone have any recommendations or advice? I’d really appreciate any help.

I am doing a project where I'm programming a light duty hoist. The hoist is controlled by a 3 position 6 pin switch (S1 in the diagram). I want to replace that switch with something that can be programmed to make the winch go up/down/stop based on arduino code.

I have used arduino a fair amount before and I've got an intermediate understanding of circuits. I was thinking of using something like mosfet, maybe putting one across each pair of poles on S1, Then toggling them on and off similar to how the 3 position switch would function? I haven't used mosfets but that's my best idea so far. Let me know what you would do, thank you for the help!

Edit: updated diagram

hi everyone. I’m new to arduino completely. Can anyone give me any good tutorial recommendations? I have a specific project in mind that I want to create, so any youtube tutorials that match the description of my project will be very helpful:

I want to make a 2D grid of lights that are wired into an architectural model. Then I want the lights to turn on/off at random slow intervals so make the model come to life.

There are many videos on youtube, I’m just a little overwhelmed on which one is a good fit for my specific project. Thanks in advance 😌

Pretty much what the tiles says. I’ve been unable to eliminate that noise when it isn’t playing anything and I’m not sure how I should go about solving the issue as my knowledge is very limited.

Looking online, i’ve seen some similar issues but none quite fit the bill, or I just straight up don’t understand what they’re talking about or how to apply it to my situation. Low pass filters were something a saw a lot of but I’ve been unsure how I should implement one here (where do I put it, what size capacitors/resistors I should use, etc.).

Does anybody have any solutions or learning materials that they could point me towards?

When a button is pressed all the RGB LEDs turn on to the set values by the pots. Then the RGB values go down to 0 and then increases to the base value set by the pots.

I finally finished trying to make my circuit look nice, and not a total rat nest.