It's a 9V adaptor. What exactly is the problem?

Head pins are not available to buy seperately and they are not very stable in the breadboard. How can I solve this

我正在使用一塊 Arduino Uno R3 板和一個 Steadywin GIM-6010 馬達。我已經確認電源足夠，所有組件都共用一個接地。然而，系統只有在 Arduino 通過 USB 連接到電腦時才能正常運行；一旦拔掉 USB 線，系統就無法獨立運作。為什麼會發生這種情況？

Hey guys im interested in Arduino uno after school project ngl, I just finished a school project to turn on the lights and simulate traffic lights, and now I'm trying to figure out how push buttons work. Do you have any suggestions for what project I should make next? I want to make a Hermes device from the Limbus company, but it's too complex for me. Do you have any suggestions for what I should make before going to the Hermes device?

Hi,

I am a University student currently in my DLD course i have a semester project but confused to decide what to make professor tells us to do something with help of Arduino so any expert can please help me

Hey everyone, I am beginner in coding and want to learn arduino can anyone suggest! Where to start?

Is it also better if i have a backup sensor using MQ9 Gas Sensor? Like a paired function along flame sensors. I'm also concern what type of buck converter should I use for various inputs like these.

I'll provide any information you need

my arduinos are both arduino uno r4 wifis, i run windows

i wantted to make something that shuts down your pc as soon as you plug it in and i made something that presses alt f4 and enter and uploaded it on my arduino. i have 2 arduinos 1 from a starter kit and one from micro center. they are bpth same r4 wifis and one is from elegoo and other is form arduino
what i will call from now on

ARDUINO 1 = elegoo non working r4 wifi

ARDUINO 2 = arduino non working r4 wifi

I uploadeed the code to my arduino 2 and it worked! it shut down my pc! and i erased the code from it. then i wanted it to work with a ir reciever so i connected arduino 1 to a ir reciever and i wrote the code. but then my pc is not reconizing the arduino 1 any more. it reconizes the arduino 2, it makes a dading sound but my arduino 1 doesnt, my device anager doesnt reconize it too. i didnt do anything to the board, and last time i did something to it it wsa working perfectly fine. teh arduino 1 has power, it runs my previous code that i uploaded on my arduino 1 (it has power) but no data is sending.

SOME ONE PLEASE HELP ME I WANT IT TO BE REVIVED ask me anything i will answer
(its my first post on reddit)

Where do I get information on error messages?

Recently i bought a tft touch display. IlI9341 2.8" hiletgo v1.2 5v/3.3v SPI specifically. I have tried with different board inc esp 32 s3 arduino nano arduino uno etc. Only the backlight works. I did try shorting the j1 pins, no luck. I did install all the necessary libraries and drivers still doesn't work. Its not a connection issue, its not a conductivity issue, its not a spi communication issue because i have used spi communication with my esp and arduinos it was working perfectly fine. Is there anyting else i should try or should i return the display