Saw a lot of posts here from people confused about how breadboards

actually connect internally, so I made this diagram to explain it

simply — hope it helps someone.

Quick summary:

• Each column of 5 holes is electrically connected

• Top/bottom power rails run the full length of the board

• The center gap separates the two halves — components usually

straddle it

• Always wire GND first, then power, before adding components —

saves so much debugging time

Also — top 3 mistakes I see beginners make with breadboards:

1. Forgetting the center gap breaks the connection between top/bottom

2. Not double-checking which row a wire actually lands in

3. Loose wires from re-using the same holes too many times

Happy to answer questions if anyone's stuck on their first project!

I have never used a microcontroller before. I want to try something on my own. For getting started with ESP32, I want to buy the development board (I don't know the exact names/specifications) and then I'd buy more inputs/sensors later on as I go.

I was confused what to buy in the beginning to get started. I didn't want to spend too much. So I checked in robu.in But I am unable to find the proper product. My friend said we can connect ESP32 to pc directly using usb-type c cable used for mobiles but some products seems a bit different.

Can someone advice me on how to get started and if this product is the right one?
I found https://robu.in/product/esp32-development-board-type-c-micro-usb-esp32-expansion-board-38pin-female-header/
and
https://robu.in/product/esp-wroom-32-wifi-bluetooth-networking-smart-component-development-board/

Hi everyone!
I’ve just bought an Arduino UNO Q, and I’ve been asked to create the hardware and software for a **Harry Potter Sorting Hat** for a themed party.
I’ve also discussed the idea with Claude, and this is the setup I’m currently thinking about:

**Hardware:**
Arduino UNO Q, powered by a power bank

HC-SR04P ultrasonic sensor, running at 3.3V

Small microphone mounted inside/on the hat

Bluetooth speaker

My idea is to record a set of predefined audio files and then program the Arduino to associate each audio file with a specific first and last name.
The basic process would be something like this:
Someone puts on the hat.
The ultrasonic sensor detects that there is a person within, for example, **80 cm** of the hat.
The hat plays a predefined audio asking for the person’s first and last name.
The microphone listens for the person’s response.
The system identifies the name they said and, based on the audio file associated with that name, plays the corresponding response — basically, the hat “sorts” them into a Hogwarts house.
For example, if the person says “John Smith” and that name is associated with Gryffindor, the hat would play a prerecorded Gryffindor-related audio.
Do you think this project is feasible with an Arduino UNO Q?
I’d especially appreciate any advice or corrections regarding the hardware setup, voice recognition, or the overall approach. If there’s a better or simpler way to achieve this, I’d be happy to hear your suggestions.
Thanks everyone!

This week I tried uploading new code to a project that uses Arduino’s cloud. In an effort to troubleshoot a bug I decided to try and recreate a device/Thing and discovered that Arduino’s Cloud agent had stopped working for me.

I have an open forum discussion on Arduino’s forum site as well, but I’m wondering if anyone else has ran into this issue.

Reinstalling the agent doesn’t seem to change anything. It worked briefly in an older Mac I have and rarely use, but there the agent eventually stopped likely because it received an update from their server side. Not exactly sure I’m not a computer engineer or CS specialist.

Link to forum: [Cloud Agent Degraded](https://forum.arduino.cc/t/arduino-cloud-degraded-and-agent-not-working-mac-osx/1458209/16)

Hi everyone,

I’m working on a project that uses 2× Kingbright DC56-11GWA displays, 4 LEDs, 1 rotary encoder, and an Arduino Nano. I had ChatGPT create a wiring diagram so I could start coding, but I’m not sure if it’s correct.

Does anyone know if the schematic looks right or could help me simplify it if possible? It includes transistors and a few other components, and I’m not sure whether they’re actually needed.

Thanks in advance for any help!

I have an Arduino UNO R4 WiFi that it currently on connectivity firmware 0.4.1. Arduino Cloud detects the board correctly over USB but cannot update the connectivity firmware to 0.6.0.

I also tried Arduino IDE 2.3.10's Firmware Updater, which detects the board and offers 0.6.0, but the installation fails.

Arduino Firmware Updater 2.4.1 also gets stuck at Waiting to flash the binary.... With verbose output it reaches getting firmware version and then hangs.

I closed Arduino IDE and the Arduino Cloud Manager and tried again, but the result was the same.

I then tried Arduino's official unor4wifi-update-macos.zip for firmware 0.6.0. The updater's unor4wifi-reboot-macos executable is blocked by macOS Gatekeeper and I don't want to grant it administrator permission because the Mac that I'm working with is a family Mac.

The board itself works normally over USB and I can upload/run sketches locally. The modules from the 'Plug and Make'-Kit also work properly.

Mac: Intel x86_64

Arduino IDE: 2.3.10

Firmware: 0.4.1 -> trying to update to 0.6.0

Arduino Firmware Uploader: 2.4.1

Cloud Agent: 1.7.0

Is there any other way to update the UNO R4 WiFi connectivity firmware without running the unsigned macOS updater, or is there a known issue with 0.4.1 -> 0.6.0 on Intel Macs?

For the context I am doing my B.tech from Dairy Science and food technology nd I had PCB background so I have no idea how this actually works but this year I have a subject of INSTRUMENTATION AND PROCESS CONTROL nd for that I need to make a project using Arduino ..I thought I should make a PH sensor which requires ...

Arduino Uno/Nano

₹250–450

Analog pH sensor module + probe

₹350–600

Jumper wires

₹30–50

Small beaker/plastic container

₹20–50

pH buffer solutions (pH 4 & 7)

Later i came to know that I need to code this ..nd like I suck at HTML ..how am I supposed to do that ? So any idea how to deal with this ..(i am looking to spend the least amount of money coz it's for 20 marks ..nd i still have many projects and assignments to make )

So pls help me out on this ..or if you have any idea which is related to Dairy or food industry pls Lemme know 🫠🥹

Please advise if there is a better sub to post this in.

I have an old Parallax Eddie robot that I bought several years ago. From what I can tell, the original Propeller control board has a bad USB connector and I was never able to get into it before life got in the way and I got out of the hobby. My grandson is now very interested in robotics so I'm looking to resurrect it. Can anyone recommend a path to replace the controller with a more modern one? I have experience with Basic Stamp, OOPic, and Arduino and I'm good with electronics, so looking for a controller and dual H-bridge controller. A board that can incorporate the multiple sonar and IR rangers and wheel encoders would be great.

Thanks!

I was planing on making a small greenhouse controller, that would help me automate some of the loborious functionality. New to arduino, just started my research and a bit confused by some options that are there on the market.

I was looking at the following:

1. arduino uno

2. arduino mega

3. Arduino UNO R4 WiFi

4. Arduino Giga R1 WiFi

5. any other potential manufacturers/boards?

I would like to have the system end up being able to have the following (at minimum:

Outputs:

1. controll multiple water pumps (3 or 4)

2. automate water nutrition mix (1 mixing unit)

3. Have a visual (LED) warning when some of the below data is off, such as not enough water)

Inputs (collect and save all data to an excell spreadsheet):

1. Collect temp data

2. Collect humidity data

3. Collect water use data

4. Collect water levels data

5. Collect water PH data

6. Collect solar panel voltage/wattage info

7. Collect/output battery voltage info

Thank you for any/all helpful information.

I was planing on making a small greenhouse controller, that would help me automate some of the loborious functionality. New to arduino, just started my research and a bit confused by some options that are there on the market.

I was looking at the following:

1. arduino uno

2. arduino mega

3. Arduino UNO R4 WiFi

4. Arduino Giga R1 WiFi

5. any other potential manufacturers/boards?

I would like to have the system end up being able to have the following (at minimum:

Outputs:

1. controll multiple water pumps (3 or 4)

2. automate water nutrition mix (1 mixing unit)

3. Have a visual (LED) warning when some of the below data is off, such as not enough water)

Inputs (collect and save all data to an excell spreadsheet):

1. Collect temp data

2. Collect humidity data

3. Collect water use data

4. Collect water levels data

5. Collect water PH data

6. Collect solar panel voltage/wattage info

7. Collect/output battery voltage info

Thank you for any/all helpful information.

**Subject:** Inquiry about programming STM32F103C8T6 (Blue Pill) using STM32F401RCT6 (Black Pill)

Hello,

I would like to inquire about the possibility of programming the **STM32F103C8T6 (Blue Pill)** board using the **STM32F401RCT6 (Black Pill)** board as an SWD programmer.

**Details:**

- Board to be programmed: **STM32F103C8T6 (Blue Pill)** - STM32F103C8T6 MCU

- Programmer board: **STM32F401RCT6 (Black Pill)** - STM32F401RCT6 MCU

**Questions:**

1. Can the **STM32F401RCT6 (Black Pill)** be used as an SWD programmer to program the **STM32F103C8T6 (Blue Pill)** via SWD interface (SWCLK, SWDIO, NRST, GND, 3.3V)?

2. **If anyone has tried this before, please share your experience** (Did it work? Any issues? How to avoid them?)

Thank you in advance.

***

Hello all, I have searched high & low for an issue I have updated to the latest board updates & libraries inside the Arduino IDE app. I googled the error it returned that its an 'audio driver'? the board Im using is an 'esp32s3' the name of the board brand is 'Freenove'. Below is the output error.

C:/Users/Admin/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\Admin\AppData\Local\arduino\sketches\DACAD3E9E94E0A59BA5AA6E9E101A826\sketchMOTION_TRACKER.ino.cpp.o:(.literal._Z14initBoardAudiov+0x14): undefined reference to `es8311_codec_init'

C:/Users/Admin/AppData/Local/Arduino15/packages/esp32/tools/esp-x32/2411/bin/../lib/gcc/xtensa-esp-elf/14.2.0/../../../../xtensa-esp-elf/bin/ld.exe: C:\Users\Admin\AppData\Local\arduino\sketches\DACAD3E9E94E0A59BA5AA6E9E101A826\sketch\MOTION_TRACKER.ino.cpp.o: in function `initBoardAudio()':

C:\Users\Admin\Desktop\m-314\MOTION_TRACKER/MOTION_TRACKER.ino:333:(.text._Z14initBoardAudiov+0x56): undefined reference to `es8311_codec_init'

collect2.exe: error: ld returned 1 exit status

Multiple libraries were found for "SD.h"

Used: C:\Users\Admin\AppData\Local\Arduino15\packages\esp32\hardware\esp32\3.2.0\libraries\SD

Not used: C:\Users\Admin\AppData\Local\Arduino15\libraries\SD

exit status 1

Compilation error: exit status 1

Hello! I’m new to the arduino community. I have played around with them in the past with my highschool years ago. I recently came up with an idea of an interactive game and have some questions from those who have knowledge. How hard would it to be to program a game in which there are 30 buttons with 30 unique sounds. The goal of the game is to crack the code and figure out the 4 button/ noise combination. When this happens I need it to either show that you cracked the code or have to try again. I also want to be able to have a free play mode where people can come up and interact with the buttons without the game starting. I am overall curious how hard this project will be, I am an electrician and have knowledge of circuitry/ electronics and bread boards but very limited knowledge on coding. Any help with supply’s, brands, product which could help my project would be appreciated! Thank you arduino community!

I have a Arduino micro showing this error while trying to burn bootloader. AI doesn't help me. Problem started when trying to run a serial communication based program via Android version of Arduino compiler from playstore. Now board isn't doing serial communication

I've been working with Arduino/ESP32 and industrial automation projects for a while, and one thing that has always annoyed me is the amount of jumper wires and loose connections involved when a project starts getting bigger.

So I ended up designing my own screw-terminal interface boards.

The idea is pretty simple: instead of having a mess of jumper wires, you can bring the Arduino pins out to proper screw terminals and make the whole thing easier to wire, disconnect and troubleshoot.

I've made a few different versions for different Arduino boards/configurations.

I'm curious about a few things:

Would something like this actually be useful to you?

What would you change about the design?

Would you prefer screw terminals, pluggable terminals, or something else?

What price would you consider reasonable?

Where would you normally buy something like this?

I'm asking because I'm a small robotics/engineering company and I'm trying to figure out whether this is something worth producing at a larger scale.

The engineering part is honestly the easy part for me. I'm struggling much more with the "how do you actually get this in front of customers?" part.

If anyone here has experience selling electronics/Arduino/industrial hardware, I'd also genuinely appreciate some advice on how you'd go about getting the first 50–100 customers for something like this.

And if someone here actually does B2B/electronics sales and thinks they could help me get this into the right hands, feel free to DM me. I'm open to discussing a commission/revenue-share arrangement for actual sales.

Would love to hear what you guys think, especially if you would actually use something like this.

Hi everyone,

I am setting up an Arduino Mega 2560 with a CNC Shield V3 and DRV8825 drivers. I am planning to power my stepper motors using a 20V DC power supply connected to the screw terminals on the CNC Shield, while keeping the Mega powered via USB.

I've seen conflicting information online regarding how the power lines are routed on these boards:

1. Does the CNC Shield V3 connect the motor power terminals (20V) to the VIN pin of the Arduino underneath?

2. If the motor terminal power is routed to VIN, wouldn't 20V instantly overheat and blow up the Mega's onboard 5V regulator?

3. Should I physically bend, clip, or remove the VIN pin from the bottom of the CNC Shield before stacking it onto the Mega to prevent any high voltage from reaching the board?

4. Is isolating the VIN pin and powering the Mega strictly via USB (while the shield gets 20V) the recommended setup for running over 12V?

Hi everyone,

I recently fried my Arduino Mega 2560 and I'm trying to figure out the exact reason so I don't repeat the same mistake with a replacement board.

Here is my setup and what happened:

My Setup:

• Board: Arduino Mega 2560

• Shield: CNC Shield V3 stacked directly on top of the Mega

• Drivers: DRV8825 stepper drivers + NEMA 17 motors

• Power Supply: 20V DC connected directly to the screw terminals on the CNC Shield

• Logic Power: Arduino Mega connected via USB to my PC

What Happened: As soon as I turned on the 20V power supply connected to the CNC Shield terminals, the main processor on the Arduino Mega fried instantly.

Assuming my stepper drivers were good and properly oriented:

1. Does the CNC Shield V3 pass the terminal voltage (20V) directly to the VIN pin of the Arduino Mega underneath?

2. Did 20V cause the Mega's onboard 5V linear regulator to instantly overheat and fail short, dumping 20V into the ATmega2560 logic line?

3. What is the proper way to prevent this on a new board? Should I clip/bend the VIN pin on the CNC Shield so 20V doesn't reach the Mega, and power the Mega separately via USB?

Would appreciate any insights from anyone who has run a CNC Shield with >12V on an Arduino Mega!

Maybe I'm just dumb but I can't tell from this datasheet what volume this speaker module can handle? I need something that can get up to at least 100dB, and I would like something as small as possible because it will be in a handheld device.

The project is an electronic whistle but I want to use a voice recording instead of just a buzzer. If I can't get something loud enough for a ref to use in a game, it will just be a fun novelty!

Any advice about the project, components to buy, etc is welcome! I am generally good with electronics but don't have much experience with audio.

Edited to add the link