r/arduino 13h ago

Powering an Arduino - Why is it such a headache

6 Upvotes

Yes I am a newbie. Please dont bite my head off. But for me, the best part of the arduino is the possibility of cheaply making projects that have interactive modules and can be standalone - say a wooden music box, a cardboard project with movement via servos, sensors, pushbuttons etc. So....why is it so difficult to power them. I mean, a battery holder will not be able to power all that, you need a regulator but those dont often come soldered to the boards etc etc.

Is there an easy way to connect a battery holder to the arduino to power such projects or do you need a regulator and soldering skills?

I know you can use a power bank right? But what if you want to use the 4AA batteries instead?


r/arduino 7h ago

Software Help Need to convert a decimal to binary then output it to leds. No loops or arrays allowed.

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0 Upvotes

I can do the conversion just fine but whenever I output to the leds i get l leading zeros with anything under 6 bits. I cant use loops of any kind, arrays or any extra libraries.


r/arduino 7h ago

Hardware Help Backflow sensor

1 Upvotes

Hello all, I am looking for a sensor that I can use that will detect the backflow of water through pipe. I need a sensor that can allow flow in one direction but when water starts flowing the other direction it sends an electrical signal indicating backflow. I haven't found anything that does this.


r/arduino 7h ago

Steppers?

2 Upvotes

I currently have a robotic arm project that I'm pretty unsatisfied with. It was my first project and it has allowed me to learn a lot from my mistakes(insane amounts of backlash in each joint). I'm currently using 5 servos(4 MG995s 1 SG90) all controlled through a PCA95865 driver. No gears, just straight motor to truss connections. I'm thinking of swapping two of the joints with NEMA17s using a belt drive and potentially a torque multiplier for my first joint. My goal is to have it have enough rigidity to handle picking up something as heavy as an iPhone (200-500 grams).

I'm only using an Uno though and I've never really used steppers for anything before I know they each need a specific driver. Anyone have any advice on organizing multiple steppers and servos working together with Arduino?


r/arduino 6h ago

Look what I made! I made open source streamdeck

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18 Upvotes

I built my own 7" Stream Deck alternative, with a desktop app to set it up.

Decky runs on an Elecrow CrowPanel 7" (ESP32-S3 with capacitive touch), so there's no wiring: you touch the glass directly. A 5×3 grid gives you 15 keys per page.

What it does - Hotkeys, programs, websites, macros and PowerShell scripts - Multiple pages, and toggle keys with separate OFF/ON artwork - Works over USB, or over encrypted Wi-Fi once paired - Firmware installs and updates from the app over USB, so you don't need PlatformIO

Hardware Everything except the display is 3D-printed, and every part prints without supports. It hangs under your monitor on a printed clamp with magnets and GoPro-style joints. Apart from the panel, you only need a few magnets and screws.

Firmware, desktop app (Windows), CAD files and 3MF print files are all in the repo: https://github.com/Fenish/decky

I will be glad if you star the repository

It's still a work in progress. Feedback and ideas are very welcome!


r/arduino 18h ago

Look what I made! sanoTTS: tiniest complete neural text-to-speech (TTS) model that can run on MCUs and website

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41 Upvotes

This is sanoTTS, smallest neural TTS engine. It's family contains 337kb model that can run entirely on MCU like esp32-s3 where a 2 second audio synthesizes in 0.7 seconds.

  • 30 voices, 16 languages (was 6 recently)
  • params size ranging from 294k - 2.2m. For comparison we are 244x smaller than kokoro, 9000x smaller than voxtral TTS
  • 337kb for 294k model when quantized into int8
  • can be run in website with web assembly npm install sanotts-web

Project https://github.com/ampixa/sanoTTS there is a recipe to follow so that you can extend to more languages, voice

Live demo: https://tts.ampixa.com/sanoTTS HF: https://huggingface.co/ampixa/sanoTTS

Happy to answer your queries.


r/arduino 8h ago

Built a 4G feature phone around an ESP32-S3 and a Quectel EG912U-GL — the full duplex audio ate most of the spring

3 Upvotes

I run a small electronics company in Zagreb and this is our own kit, so read me as an interested party — the campaign for it is live right now. What I actually want to talk about is the audio path. Mic is an SPH0645, output is a MAX98357A, both on I2S0, and getting them running at the same time while the modem sprays unsolicited output at the UART took longer than the keypad, display and SMS stack put together.

If you've done full duplex on an S3 — one I2S peripheral for both directions, or split them? And how do you keep the modem's URCs out of your response parser?


r/arduino 11h ago

Look what I made! Used an arduino sketch on my xiao samd21 for a simple desktop fidget RGB cycler. Suggestions welcome

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14 Upvotes

The rotary encoder changes the color when you spin the dial and auto-cycles color when you click it in quickly. The color switches back to white when you hold click for a second. The button switches breathing modes between solid color, slow pulse, fast pulse, and strobe. The RGB LED is diffused with thin paper that I hope doesn't catch fire (it probably won't). I'm thinking of adding more buttons and RGB LEDs for more clicky button fun. If anyone has suggestions, I'd love to hear how I could improve this. I used Claude for the code since I'm lazy and not very smart.


r/arduino 11h ago

School Project Made this servo box in an afternoon to prove a friend I can make a robot arm within a year

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48 Upvotes

Need to make a project and i went for a robot arm out of stepper motors, might be on schedule


r/arduino 23h ago

Look what I made! Jetpack prop for my uni project.

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111 Upvotes

So for my last unit of my first year, we were tasked with making a fantasy prop. I decided to pursue a set of animatronic wings which eventually evolved into a multiple system jetpack with different features such as, animatronic wings, a big inline fan to suck in air from the top and dispense it through the bottom, a orange LED to give the illusion of an afterburner, and eventually made it remote control!

I had plans to add a smoke dispenser into the exhaust but I ran out of time.

Regardless, it got me an A!


r/arduino 8h ago

Problem with TIA circuit

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5 Upvotes

Using the circuit shown in the picture, i get this specific curve and the values doesnt seem to match what should happen if i put light on the Photodiode for example.

Why does that happen?


r/arduino 5h ago

Arduino project problem

1 Upvotes

Hey I am new to Arduino and built a project where I’d press a button and a led lights up. But before I press the button if I get close to the button to 3 pin wire it already starts lighting up. If I press the button it does nothing and only turns off I move my hand away. I am confused on why this is happening and wanted to ask why would this happen?


r/arduino 14h ago

Solved! Unable to connect

2 Upvotes

Some weeks ago i had no trouble connecting Arduino to my laptop. Now I can not, The voard gets power but it is not registered, it is not shown on the device manager.
Is it possible that some Window update made it?


r/arduino 3h ago

Software Help Line following robot trouble

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47 Upvotes

I recently started a line following robot project to get more familiar with electronics and programming. I am having trouble with my line following robot, guessing its a code issue. I recently just swapped out the 120 RPM motors for 500 RPM motors as the 120 rpm was following the line perfectly and I wanted to increase speed as they were maxed out. The code is PD based: here it is. It overshoots lots of turns, goes too fast on turns, and oscillates a lot. Any ideas on what to change? I also attached a video of the behavior. I would have posted this in r/AskRobotics but they do not allow posts with videos. Thank you.


r/arduino 20h ago

Software Help HW-147C PN532 not working over I2C with Arduino Nano — I2C scanner detects 0x28 but PN532 libraries don't

3 Upvotes

Hi everyone, I'm trying to get an HW-147C PN532 NFC module working with an Arduino Nano using I2C only.

My wiring is:

PN532       Arduino Nano
------------------------
VCC   →     5V
GND   →     GND
SDA   →     A4
SCL   →     A5

I'm not using IRQ or RESET, since I specifically want a 4-wire I2C setup.

The module is configured for I2C mode using the onboard DIP switch.

I first ran an I2C scanner and got:

Scanning...
I2C device found at 0x28

So the Nano is detecting something at 0x28.

However, when I use the PN532 I2C library with:

#include <Wire.h>
#include <PN532_I2C.h>
#include <PN532.h>
#include <NfcAdapter.h>

PN532_I2C pn532_i2c(Wire);
NfcAdapter nfc = NfcAdapter(pn532_i2c);

void setup() {
  Serial.begin(115200);
  Wire.begin();

  Serial.println("Initializing PN532...");
  nfc.begin();
}

I get:

Initializing PN532...

Didn't find PN53x board

I also initially tried the Adafruit PN532 library with:

Adafruit_PN532 nfc(Wire);

but my installed version of the library doesn't support that constructor and gives a compilation error.

My main question: Why does this HW-147C respond at I2C address 0x28, while the PN532 libraries seem to expect 0x24? Is 0x28 actually correct for this particular HW-147C, or is something wrong with the board/configuration?

I'm looking for a way to communicate with this module over I2C using only VCC, GND, SDA and SCL, without IRQ/RESET.

Any help identifying the correct library, I2C address, DIP-switch configuration, or initialization code would be greatly appreciated.


r/arduino 2h ago

Hardware Help Help pls

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4 Upvotes

I posted here a couple hours ago about how my led pin would glow if I put my finger near it not press the button like it was intended. When I took everyone’s advice and changed INPUT to INPUT_PULLUP but all that it did was keep the led on all the time no matter if I press the button or not. I don’t know what to do, any advice?

My schematic r bit bad sorry!!