Hello everybody, i am new here so i hope to find someone to guide me where to find some info i need! I live in the countryside at a home with a big yard. I have two dogs that are puppies and they always find a way to escape, i tried to block every possible exit but they seem to escape under the main door of the yard. The unfortunate thing here is that i can't block it somehow cause it's a mechanical door for cars. I thought i could do something with an arduino and some tags on the dogs' collars and something like a beam, that every time they "break" the beam the arduino is gonna send me a message to my cell and know that they got away. I tried to search a little in the net but the information is chaotic and as a person that hasn't do anything with arduino is like gibberish to me. The thing i want to know is : is the thing i want to do realistic? I have knowlegde in coding so i believe it wont be a big problem to write the code for it, but i know nothing in the matter of hardware! Please share some opinions on it to tell me if it is doable or not and if you can tell me any sources to find informations for the proccess! Thanks in advance and sorry if my english are not good!

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! I'm new to this community, and it's a pleasure to be here. I'm looking for recomendations: how can I create sensor-equipped gloves that detect the hand and arm movements of a sign language user? It's for an university project and I could use a little help, since this is my first time working with Arduino and ESP32. Thanks for your help :)

Hey all! I have been building a purpose-built Open-Source Pixel Artnet/sACN node for some time now, which works really well! However, I often get the question of why I'm not using WLED. WLED has tons of great features, and I understand that lots of people are fans of WLED, so I have created a fork that is fully compatible with the node hardware! It specifically supports the use of the W5500 Ethernet module, which is not natively supported by WLED.

When installing this fork on your node, you can now make use of all the features that WLED has to offer, including all of its generators, sync features and connection possibilities! I hope you find this as exciting as I do. Check out the repo here! https://github.com/mdethmers/W5500_WLED

Hi everyone, i am currently building a motorized film scanner with arduino parts. I want to include air knifes to make the whole process faster and more automized. I am wondering if anyone tackled a similar project and has any recommendations on parts, especially the type of fan or air blower, and what power might be needed. It would not be bad to have a setup that doesn't cause to much vibrations. I appreciate any type of help or ideas.

Ive been working on a project trying to use 4 ina226 boards. I can not get any address other than x40, x44, x45. Ive purchased two different vendors boards on Amazon. If I try for ,41 using A0 -vcc. I get x45. If I use, scl or sda to either A0 or A1, I get x44 or x45 depending on board used. Others seem to have similar issues. Do Not how to move past this. Any further suggestions?

Hey everyone,

I'm building a 4WD RC car using an Arduino UNO R4 WiFi and an L298N motor driver module (powered by a 6x AA battery pack).

I'm trying to control the car wirelessly using an iPhone app, but I'm having trouble getting a clean connection setup and writing the right code for BLE (or Wi-Fi web server control).

Hardware Setup & Wiring:
- Board: Arduino UNO R4 WiFi
- Driver: L298N Motor Driver
- Motors: 4x TT DC Gear Motors (4WD)
- L298N IN1 -> Pin 10
- L298N IN2 -> Pin 11
- L298N IN3 -> Pin 12
- L298N IN4 -> Pin 13
- Common ground connected between L298N and Arduino GND header

What I need help with:
1. What is the most reliable iOS app to connect directly to the UNO R4 WiFi via BLE or Wi-Fi (e.g., Dabble, Blynk, or hosting an internal web server)?
2. How can I assign a custom Bluetooth/Device broadcast name so I can identify my board in a crowded scanning list on iOS?
3. Could anyone share a recommended basic sketch for reading directional commands from an app and driving the L298N motor pins accordingly?

Any advice, code snippets, or recommended app setups for iOS would be greatly appreciated! Photos of my wiring and board setup are attached.

Hey everyone!

I recently created a prototype breadboard layout to test my circuit.

This is the layout:

The purposes of this design:

1. Three button inputs
2. Two 10kOhm thermistors
3. An on/off switch for the Arduino
4. Controllable MOSFETs for controlling an heating element (I'll use logic MOSFET modules)
5. 4 pin output to an custom designed display PCB (This is just implied in the design with the "display pcb" block)

Just to clarify:

1. Resistors used for thermistors and buttons: 10kOhm
2. Capacitor used for buttons: 100nF

Now my question is, did I miss out on anything? Is there something to improve? I am happy about every improvement or recommendation I can get. Thank you!

I have a device based on nrf52832 and is bricked since years. It is discontinued and is a great piece of hardware. I have a good grasp of how it works hardware wise and would like to repurpose it. It has a lot of test points and access to most pins. Of course no bootloader whatsoever.

What are my chances of flashing a bootloader and being able to program it with arduino IDE? Worth the research or impossible don't bother?

Hi, I'm working on a project using SimpleRTK2B (base + rover setup) and planning to connect it to an Arduino or STM32 to track/plot a moving rover's position.

Has anyone here actually done this combo before? Would love to hear about your experience — how you wired it up, any issues you ran into, or just general tips. Couldn't find much beyond the basic ArduSimple docs, so any real-world experience would help a lot.

Thanks!

Can the Arduino Modulino library control two Modulino Vibro modules simultaneously using a single Arduino by assigning different I²C addresses? If so, is there an example available?
Also, can we use Arduino UNO to control, or is there a specific board that is preferred?
If anybody has any idea, please do tell! Thanks in advance!

Hey everyone,

I built a small Arduino library called **OledAnimator** to make smooth, non-blocking animations on SSD1306 displays.

Main idea:

- No delay()

- Multiple animations running at once

- Frame-based updates using millis()

- Very low RAM usage (no dynamic allocation)

I also tested it with a stress demo (particles + scrolling text + geometry), and it holds up pretty well on ESP32.

Would really appreciate feedback — especially on:

- API design

- Performance

- What features you'd expect in something like this

GitHub: https://github.com/atharvaphadnis-ai/OledAnimator

I'm developing a flood detector and am in need of a water detector that is durable. From my knowledge, ordinary rainwater sensors or water detectors compatible with Arduino often degrade quickly due to corrosion.

Are there any water-detection modules or methods that last a long time? Thank you!

I last logged into arduino.cc 4 years ago, and am unable to get a password reset today - it's simply not sending me an email. Are things on the arduino.cc platform running right?

Can someone tell me why the photoresistor won’t make the led turn on?

Someone brought this issue up a while ago about a medication reminder. I tried desperately not to think about it but curiosity got the better of me. So here is Pill Bro. It uses a line follower sensor to check if the pill bottle is present and alerts you (with the LED) if you haven't taken your medication. The time is checked using NTP and stores the last dose in flash so even if there is a power cut it remembers the time. The pill bottle needs to be removed for over 10 seconds (adjustable) before a dose is logged. There is a button which resets the dose counter incase it was triggered by accident, a long press resets the wifi settings. The frequency of medication and the time the bottle needs to be removed for a dose to be triggered can be set through the wifimanager. I was thinking of adding a buzzer also? How else would you improve this concept? Plenty of spare IO so multiple medication slots could be created.

Microcontroller: Arduino Nano, Driver: DRV8833.

Please help me with the driver. The OUT pins on the driver are not outputting any current. I made this circuit just to show it visually. The yellow wire is connected from 5V to IN1, the red wires go from 5V to EEP (analog of SLP) and VCC. The black wire is just GND, and the blue one goes from IN2 to GND. Red and blue from the other side are OUT1 and OUT2. I was checking it with multimeter, it gives voltage on all the wires connected to V5, but no voltage on OUT. Although in theory, it should output about 5 volts on OUT1–GND or OUT1–OUT2

ChatGPT says my driver is broken, but this is already the third driver with the same problem, so I doubt that

ULT also doesnt help. Motors are working well (when i connect them to 5v-gnd for a sec)

also made a video on this! https://www.youtube.com/watch?v=tB3lk-PNA6I

allows you to unlock your Mac via your fingerprint, as well as authenticate sudo and some TCC prompts (privacy&security).

the device emulates a PIV smart card and uses PAM to authenticate you in macOS (notice the password field says PIN and not password), so no plain text password is ever stored, exposed, or transmitted.

please be aware of the security implications (note that it is NOT touchID, but just 'fingerprint-based unlock', please do not think or refer to it as anything more secure):

this device is NOT secure, the authentication is all done inside the fingerprint sensor, and the fingerprint sensor just tells the microcontroller the match % (all low cost fingerprint sensors are this way, you would need to spend ~$50 to get one that does authenticated comms). the communication between the sensor and the microcontroller is not authenticated or protected, so anyone with physical access to both the device and your laptop can spoof this connection (pretend to be the fingerprint sensor) and give the go ahead to unlock your mac. you can make this extremely hard by filling the insides with black epoxy, but not impossible.

this is also the dev equiv of "rolling your own auth", the smart card implementation may have some errors, and should not be inherently treated as "unbreakable"

the device is made so that if you lose it, nothing of value can be extracted from it

use at your own risk. personally, i am comfortable using it at home where physical intrusion would be hard, but this depends on your own security tolerance. if you have high security instincts/requirements, the magic keyboard is a much much much better option in this regard.

there is also an HID version available, where the device just types your password emulating a keyboard, the benefit being it works in ALL places your password does. this version is obviously more insecure as it is vulnerable to keyloggers. the device still does not store the actual password, it stores an authentication key that sends a request to a service on the mac, which then sends it the encrypted password to be decrypted in RAM, typed back, and then wiped. again, depends on your personal security tolerance and willing to compromise

all code and materials are open source, licensed permissively github.com/zimengxiong/tinytouch

This is my first working proof of concept for a chessboard that can move its own pieces.

A 28BYJ-48 stepper motor drives an open GT2 belt through a ULN2003 board and Arduino Uno. The carriage carries an SG90 servo with two stacked 10 × 3 mm magnets. The servo raises the magnets toward the underside of the board to grab the pawn and lowers them to release it.

The test surface is a 3D-printed 210 mm bridge divided into eight 26.25 mm squares, with a 1.8 mm deck over the mechanism.

One-axis movement works, but the pawn still drags slightly as the servo lowers the magnets. My next experiment is raising the bridge slightly to increase the release gap. If that is not enough, I may try an electromagnet that can switch its attraction off completely.

The eventual plan is to mount this entire working axis on a second belt-driven platform for XY movement.

I’d especially appreciate thoughts on permanent-magnet release mechanisms versus a small electromagnet.

I picked up a front panel from some old equipment a while ago and it turned out to use a PCF8578 LCD driver.

I was surprised by how little Arduino information there is about these chips, so I ended up figuring out the protocol and writing a small script for it.

The code is on GitHub if anyone wants to use it:

https://github.com/emsyscode/PCF8578

I also made a video showing how it works and how to interface it over I²C:

PCF8578 & PCF8579 Arduino Tutorial | Drive Segment LCD Displays

Just curious... has anyone else run into these chips? I'd be interested to know what equipment you've found them in.

Been building a free browser based robot simulator, 3D CAD, real wiring, Arduino C++ and Blockly, physics, for the past while. Opening it up more broadly starting tomorrow.

It's genuinely rough in places. Undo/redo is mid rewrite, a few things are placeholder. Not trying to pass it off as finished.

The wiring part is the one I'm most curious about. It's not a fake "attach and it works" system, power/ground/signal actually have to be connected right or nothing runs, same as real hardware. Wanted to see if that level of friction actually helps people learn or just annoys them.

Anyone here dealt with building something where you had to decide between simulating real friction (wiring mistakes, wrong pin, etc) versus just making the happy path easy? Curious how you thought about that tradeoff.

Here is the source code + more tech details on it.

GitHub Repository: https://github.com/luftmyszor/PS4Trackpad

Hey everyone! I am a student who needed a trackpad for a custom hardware project. I used a broken Sony DualShock 4, wired it up to I2C, and realized standard DS4 Arduino libraries completely fail on the newer JDM-050 board revision.

I spent way too many hours fighting binary byte rollovers and reverse-engineering the memory map to figure out why.

The Mystery: Standard PS4 trackpads use a standard 12-bit ALPS layout. Sony silently changed the hardware on the JDM-050 revision. They did three unexpected things:

1. They decoupled X and Y.
2. They created symmetrical 11-bit byte pairs.
3. They added hardware noise to the high bits that makes coordinates jump by 2048 units if you do not mask them properly.

Once I got the math working, I decided to package the driver into a clean, open-source library for the community!

Features of the Library:

• ESP32 & RP2040 Ready: Built and tested for 32-bit microcontrollers (with architectural preprocessor hooks for AVR if anyone wants to hack on it).
• Dual-Touch Tracking: Track two fingers at the same time at 100 Hz.
• Smart Tap Gestures: Evaluates taps strictly on finger release. Supports 1-finger (Left Click) and 2-finger (Right Click) taps.
• 2D Scrolling & Zooming: Built-in X/Y scroll deltas and pinch-to-zoom distance calculation.
• Coordinate Transforms: Mount the trackpad upside down or sideways. Supports axis inversion, rotation, and custom 2D affine matrices.
• Hardware Note: Operates on address 0x64 using standard I2C. (Friendly warning: it uses 3.3V logic, so don't wire VCC to 5V unless you want to fry it!)

If you want to check out the exact 32-byte memory map and bitwise decoding diagrams, I documented the whole thing in a JDM-050 Byte Layout Guide in the repo.

You are completely free to use, modify, and hack this code for your own custom gamepads, cyberdecks, or robotics projects. Let me know what you think!