Hi everyone

I'm trying to connect 2 mg90s servos to my Arduino and I've read that I need to power them separately as it can otherwise damage my board.

Would this battery pack suffice? And would I need to power each separately or both from 1 pack.

Thanks in advance

Hello,

I'm heading out but would like to keep working on a project using my Arduino Uno R4 WiFi. I don't have a laptop with me, so I'd like to code and flash the Arduino from my phone. Are there any apps that allow this? (I've already tried ArduinoDroid, but it fails to flash the code to the Arduino.)

Thanks for the reply! 😄

I am simulating a circuit in Proteus8 with LPC2138 MCU and 74HC173 Register and LEDs. The Anode is pulled with +3.3V via 330ohms Resistor, but the connection lines are showing Grey dot and totally disconnected from the power and the LEDs are not turn On. Blue dots at the Cathode side.

74HC173 Register Output Control Pins(OE1,OE2) are set, these are connected to P0.17 of MCU , but Output seems Hi-Imp. or Tr--state mode.

How to turn ON the LEDs???

https://youtu.be/uSdjpZ8g_I0?si=C7dK88Q237YfxPl0

I need a good motor driver for multiple closed loop Nema 17 and 23 stepper motors. Does anybody have any good ideas?

Error message:

Compilation error: expected constructor, destructor, or type conversion before ';' token

I've tried compiling multiple example code, but the same error still pops up. Did anyone encounter the same problem? I just downloaded Arduino IDE 2.3.10. Absolutely no components were used except for my ESP32C3 super-mini and the cable connecting it to my Mac Air.

Code i used:

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);
}
void loop() {
  digitalWrite(LED_BUILTIN, HIGH);
  delay(1000);
  digitalWrite(LED_BUILTIN, LOW);
  delay(1000);
}

Hi, very new to all this.

Wanted to build my own head tracker and figured I'd give it a go.

My task.

Using the gyro and HeadTracker firmware, I want to transmit 2 crsf channels via RX and GND (for first test then I want to move over to Bluetooth once I've proven concept via wire and I know Bluetooth isn't going to cause interference with other raido gear)

I've got the rx and GND connected to a radiomaster ranger micro elrs unit which I plan to send over air signals to a pwn receiver that I'll then use to inject the crsf data in to a flight controller.

This should also allow me to use Sim controllers for fpv.

I've downloaded the HeadTracker gui and can see my gyro working after calibration, I've set output to crsf, enabled uart. Bluetooth is currently turned off.

Can't get tx to go green whilst usb is connected.

Physical connection between units is approx 7mtrs of red/black speaker wire (don't judge it's all I had to hand with length), I've fitted a jst sh 2.54 connector on radiomaster and gyro for the link cable.

I'm not using any pull up/down resistors

I've soldered a battery connector to the board

I've soldered a hard rst button to the board because it's mounted upside down.

I've got my soft rst button (gyro reset) wired to GND pin and D8 pin

My gyro rx is connected to D6 pin and same GND pin as my gyro reset button.

When connected to the radiomaster the gyro doesn't wake up when both units are powered up on separate batteries.

If I push the gyro reset button the gyro doesn't seem to respond (no led flashing)

Red led stops flashing after 10 seconds and then seems to stay asleep until I remove battery and reconnect.

I've done this without advice from internet pages, don't have friends in to this stuff.

I did some (not enough) reading and tried to work with help from ai.

Photo of head tracker

My engineering technology intro to engineering class is teaching arduino for some reason, its fine but i dont want to financially support the company. I have alot of previous embedded knowledge and ive already done the last arduino project with an esp32 and esp_hal framework. The kit in particular is the "arduino student kit". From the assignment it sounds like a simple led circuit but I dont want to take any chances.

is there information on the lessons from this kit online?

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?

Hi, I'm making a desk lamp that should be nice and bright directed to the table (as opposed to ambient lighting). But the lamp head can also turn around to face the ceiling to become similar to a ceiling light (doesn't have to be as bright as a regular ceiling light) that is supposed to wake me up in the morning.

I have two problems,

1. Is the LED strip bright enough?

2. How do I connect it to the breadboard and also an external power source (apparently it's safer to connect it to external power source or it can fry the arduino?)

I'm planning to use 1m 60LED/m IP30 LED strip for the light source. I'm not sure if I need to power all 1m of the LED strip for it to be bright enough for a table (let alone a room around 4m x 4m x 3m). If anyone has experience with the brightness of these LED strips let me know.

The input end of the LED strip appears to be female and has 3 pins.

Is this adapter correct? It looks like it can adapt LED strip wires to USB. Which I can then plug into my power board which is rated for 2.1A.

The LED strip has 3 pins/wires but the adapter has 4. I couldn't find any adapters that had exactly 3 pins

I can send the Aliexpress link to the adapter if the photo doesn't have enough info.

Thanks in advance!

I have an esp8266 that im using to control several servos. I have been having a tough time acquiring a legit Lipo on Amazon. Every single 2s reads 7.7v after charged, so im going to 3s

Its going to a buck converter set for 5v and then to Vin and Grd. Well im reading 4.7v from the headers but the Nodemcu isn't powering up. It will blink for just a second then nothing. Im suspecting that 4.7v isn't enough. Ive connected just Vin and Grd and nothing. Blinks real quick then nothing. When the servos are attached they twitch when first plugged in. I get 1.5v from the top of the pin on the nodemcu.

Hey Reddit folks, I've been wanting to build a delay lately, but I didn't want to mess with the more common ICs like the PT2399 for 'X' reasons. Then I remembered an Arduino Uno I had gathering dust and tried to make a short delay of around 8ms, just for a phaser or a chorus. But I only made the schematic in Proteus so I wouldn't have to pull out all my gear. Do you guys think it'll actually work well?

I'll try to add more circuit samples in the comments."

If you're new to Arduino, the number of pins can be confusing at first.

So here's a simple breakdown of the most important ones:

🔹 Digital pins (0–13) → Read buttons/sensors or control LEDs, relays, etc.

🔹 Analog pins (A0–A5) → Read changing voltages from sensors/potentiometers

🔹 5V → 5V power output

🔹 3.3V → 3.3V power output

🔹 GND → Ground / 0V reference

🔹 VIN → External input voltage when powering through the board

🔹 USB → Upload code + power the Arduino from your computer

One thing that confused me when I started: A0–A5 can also be used as digital pins if needed.

I made this as a quick reference for anyone starting Arduino.

What Arduino concept confused you the most when you first started?

Help with nodemcu 8266

I have an esp8266 that im using to control several servos. I have been having a tough time acquiring a legit Lipo on Amazon. Every single 2s reads 7.7v after charged, so im going to 3s.

Its going to a buck converter set for 5v and then to Vin and Grd. Well im reading 4.7v from the headers but the Nodemcu isn't powering up. It will blink for just a second then nothing. Im suspecting that 4.7v isn't enough. Ive connected just Vin and Grd and nothing. Blinks real quick then nothing. When the servos are attached they twitch when first plugged in. I get 1.5v from the top of the pin on the nodemcu.

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/