Questions tagged [pins]
"Pins" are like gateways between the Arduino code running on the chip and the components attached to Arduino. It can refer either to the physical connectors on the board, or it can refer to the pins defined in the code.
467
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If Arduino digital pins can be used as power supply pins then why do we need VCC pins? [closed]
If Arduino digital pins can be used as power supply pins then why do we need VCC pins?
VCC pins work the same as digital outputs , don't they? So why do we still need VCC pins to
power components
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Duinotech ATTINY85 Pinout
I'm sure this is a super nooby question but,
what is the pinout of the Digispark ATTINY85 Development Board
The board looks like this:
Now the reason why I'm asking this question, when I do ...
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1
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I'm using nRF2401 and in my transmitter and receiver the Rx is not blinking and Tx is blinking; why does Rx not blink?
I did a search on the meaning of RX and TX and it seems TX means sending data and RX means receiving data.
So when my transmitter is turned off, my receiver looks like this and it works with a battery:...
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2
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1
answer
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What components can be connected to pins 0/1 (RX/TX) without preventing uploading of code?
For a robot project I am using an Arduino Uno, and am running out of pins. The simplest solution would be to use digital pins 0/1. I know this means that I won't be able to use Serial communication (...
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3
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1
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Why am I reading only zeroes from PORTB?
I am using a custom Arduino Nano compatible board with an Atmel 328P. I am externally changing the values applied to several pins on PORTB. I expect to be able to read the values of these pins (low ...
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2
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1
answer
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Safe to solder a slide switch to unused GPIO pins?
I have a Digispark Rev.3 Kickstarter with ATTiny85 (see pinout below) and a three pin slide switch (see example below). I want to use the slide switch to control a task running on the Digispark, with ...
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3
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2
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How to toggle a pin (LED) simply
I am not a programmer but rather a hardware guy. In the good old machine code days, you could 'read' the status of the port and flip it.. admittedly a much simpler processor. Is it not possible to do ...
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How do I instruct the L293D to operate a motor at full speed when using 3.3V GPIO pins?
If the L293D enable and input pins expect [up to] 5V inputs; what is the best way to deliver full power to the output pins when using an ESP32 or any other microcontroller which uses 3.3V GPIO pins?
I'...
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How to use ESP-01 GPIOs for input?
I'm trying to use one of ESP-01 GPIOs as an input, however, I'm always reading 1 and nothing attached to these pins.
Basically, I'm trying to detect high voltage from another sensor like a touch ...
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1
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Can pin mode damage Arduino with connected electronics?
I am not that experienced with electronics, so this might be a silly question. But I dont know. Assume that I have connected some electronic circuit (transistors, leds, anything else) to the Arduino ...
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Can I use AREF to supply a circuit, when in internal mode? (Nano)
When analogReference(INTERNAL) is set (1.1V), can I use the AREF pin to supply a circuit? E.g. like this:
AREF —— R1 —— button switch —— A4 —— R2 —— GND
where A4 is configured as analog input (...
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Why are the pin numbers of the diagrams and of the code different?
If I search Google for "arduino nano pin numbers", all results show that the pin number of D2 is 5. But that did not work. I searched for some sample codes, and they were 3 for D3 and 5 for ...
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Problem Using pins A4 and A5 for input and output I2C
Hardare used:
Arduino nano ( old Bootloader )
Oled Monochrome Display ( 4 pins, 128 x 32 )
MPU 6050
Both display and MPU use A4 and A5 as I2C communication protocol, They interfere, as the MPU is used ...
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1
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Arduino UNO won't move servo
I have a simple MG996 servo motor and I am trying to make it move with my Arduino Uno. I tried different ways of wiring but nothing seems to work as fully expected.
For the wiring I followed this ...
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2
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Input vs input_pullup
I'm a beginner in Arduino and can't understand some things. How does input pin in Arduino work? I want to set one of the pins as input. When should I use input and when input_pullup? What are the ...
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Safe to power LED strip via ESP32 GPIO
I want to rewire a battery powered LED strip (as shown in the picture below) to power via an ESP32's GPIO pin. I have a ESP32 NodeMCU Development Board, powered via USB.
The LED strip has specified 3,...
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0
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Can I support all these sensors? Will I have enough pins?
So i'm new to arduino and i'm working on a project that will require 3 modules/sensors.
I wanted to know, can all of the following modules work with the arduino mega 2560 that comes with this
touch ...
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4
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1
answer
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Custom LED toggling function: one out of three LEDs misbehave
I connected three LEDs to an Arduino Uno and wrote a simple LED class. I toggle all the leds the main loop, but for some reason one led (connected to pin7) always misbehaves, skips one toggle or stays ...
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Select pin to connect RF receiver
I use the RCSwitch library receive signals with a RF receiver. I really need to change the pin the receiver is connected to on my Arduino Uno.
What should I change in my sketch?
What pins can I ...
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1
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Accessing Physical Pins in Arduino Due from Arduino IDE
It is possible to access the Physical Pin 93, Pin PC11 on ATSAM3X8E in Arduino Due from the Arduino IDE?
I am programming a Barebone ATSAM3X8E, and it do not seems to be allocated by Arduino Due nor ...
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1
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Wirelessly (but fast) transfer STEP and DIR output from Arduino to stepper driver
Very short version:
Looking for a way to wirelessly get STEP and DIR signals (only those two signals) from an Arduino to a DRV8825 stepper driver about a meter away:
Arduino -> STEP and DIR IO pins ...
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How to connect an Output to a Pullup Input of another arduino
:tldr; Could problems occur if one connects a HIGH Output of one arduino to a PULLUP_INPUT of another while using differed power sources?
Hi I'm building some devices for a LARP Dungeon (think Escape ...
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4
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Can internal and external pull up/pull down resisters be used together?
What happens if a sketch uses code like pinMode(18,INPUT_PULLDOWN) to configure internal pull-down (or pull-up) resistors, but is used in a circuit where external resistors are also present?
Are there ...
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Check pin capabilities at compile time
Are there board-independent functions to check pin capabilities at compile time? I.e.
Can the pin be used as output, as in digitalWrite()?
Does the pin support PWM, as in analogWrite()?
Does the pin ...
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0
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How to avoid two arduino components using the same digital PIN [duplicate]
I'm trying to build an Arduino project where it involves a TFT and an ethernet W5500 component.
Here's the project I want to build to learn Arduino. However I wanted to change the board that already ...
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0
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Can I create an hemi-cycle raising signal with one pin and the other hemi-cycle signal with another pin?
I am new to Arduino, I would like to know if someone could help me to create this type of signal with the Arduino Uno. Many thanks!!
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Touch sensor trouble
I need help I use Touch Sensor(T)v.0 and it always receives a signal not matter I touched it or not.
Here is the code.
#define TOUCH_PIN 7
int touchVal = 0;
void setup() {
Serial.begin(115200);
...
2
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1
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Can't Turn Off Internal I2C Pull-Ups on ESP32
I've designed a custom ESP32 board around the WROVER-IE module. To keep power low, I'm using a GPIO-controlled high-side FET to turn off unused peripherals when in deep sleep mode.
The issue: I've ...
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I have five pushbuttons that refer to a specific pin number. I need an efficient code to set the variable for the pin with state 1. What can I use?
There are 5 push buttons each which correspond to a certain pin let us use 1 to 5 for an example. I want to set a variable, ActiveButton which will be set equal to the the only pin in the one state.
...
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Directly synthesising an OOK modulated LF signal using a CSV file
I'm looking to transmit some data (CSV files) from a measurement instrument underground to a receiver on the surface. I've learned that in order to penetrate the limestone, low frequencies have to be ...
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0
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Trouble with laser sensor
I have trouble with my laser sensor it doesn't work properly. When I connect all pins its doesn't work, when I remove GND and connect just the signal pin and VCC it works but the laser light is dim(I ...
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Does setting a value always mean setting a Arduino pin?
One thing that always confused me was why we use int or other commands to set the variables to have pin numbers as if those commands were always restricted to pin numbers only. For example
int ledPin =...
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2
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Portenta pinouts for ADC
I wanted to have your comments about one of my questions.
I am currently working on the sketch for the Arduino Portenta H7. However, due to my poor electrical background, I would like to ask your ...
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What is the pinout of the Arduino MKR motor carrier when using external power supply, not the Li-Po battery
I see there is a blue terminal connector an the tags below the PCB Vin, 5V, 3,3V and GND, but I am unsure where should I supply voltage to power up the board.
Also, in the product page it says the ...
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2
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Switch on the piezo emitter for a short time
I need a short beep for every minute of change. I wrote a separate function. The signal duration should be 50 ms, the rest of the time the emitter connected to the A1 contact should be silent.
A ...
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3
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Short circuiting GND and power pins
I have created an arduino shield and i want to measure the voltage between the GND pin and 5V pins, to see if i see a voltage difference between the two points, in order to test if my pcb is fine.
My ...
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Cant find Sdl and Sca pins in lcd display
My project is of non contact temperature sensor.I am using RG1602A lcd display and mlx90164 temperature sensor.
But the problem is, there's no sdl , sca pins in my lcd display.
Is there any way, to ...
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1
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D1 mini esp8266 error: esptool.FatalError: Failed to connect to ESP8266: Timed out waiting for packet header
I am pretty sure this device worked yesterday. I tried to short GPIO0 to ground (flash), nothing.
I have a second ESP that uploads fine, but this one does not.
Is their another way to get this ...
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3
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How to power Arduino Uno from L298N motor driver's 5v terminal?
I am trying to setup L298N motor driver controller with my Arduino. Different online schematics about how to connect them are mostly similar - but they differ in powering the Arduino from the drive ...
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Using same GPIO pins to control multiple stepper drives
I have an Arduino Mega 2560 and I want to control four 23-frame steppers same speed/direction for a conveyor application. I want these to be synchronized exactly as possible for smooth operation.
Can ...
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0
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ESP-01 and HC-SR04 problems booting up
I have a problem in a project that I am working, basically I need to use a ESP-01 to receive the measurements from a HC-SR04 and send it to another ESP-01 (which I won't cover here).
Basically my ESP ...
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1
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What pins to use on a Teensy to get data from multiple peripherals?
I'm using a Teensy to keep records on the location, speed, altitude, and direction of a weather balloon I'm hoping to launch. I have an Adafruit LSM9DS1 and a Ublox NEO-M8N with compass (HMC5833L) so ...
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Use a simple LED with no digital pins to spare
Problem: I've made a circuit consisting of an 8x8 led matrix, which uses all of the digital pins on the Arduino UNO board, and I want to add an LED too it.
I tried looking around the internet but so ...
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Conflicting pins between the PCM library and speaker and the NRF24L01
The PCM library uses pin 11 and the NRF24L01 also uses pin 11. I am using an Arduino nano, and don't know if there is any way to change the pins of either the speaker or the transceiver.
https://...
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Is it possible to configure uboot without the "Yun Serial Terminal" sketch by using the hardware serial on pins 0 and 1 instead?
Trying to rescue a Yun with the 1.5.3 image.
It's not possible to upload the required "Yun Serial Terminal" sketch because the device hangs at U-Boot (hence the rescue attempt).
Using putty ...
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1
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Do the I/O pins on Arduino read current or voltage?
So I've recently started Arduino and I just had a question about the digitalRead() function.
Does the IO Pins read Voltage or Current?
The reason I'm asking is because of the attached circuit.
So IO ...
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2
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Unable to use analog pins as digital inputs
I want to use the analog pin A7 as a digital input pin. As stated in the Arduino docs the analog pins can be configured in the same way like any other digital pin.
However, when trying to configure an ...
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Onboard led HIGH and LOW seems reversed
On an ESP32 board I am trying this simple code to control the onboard led.
But if I set it to HIGH, led is OFF, if I set it to LOW, led is ON (fully bright).
What could cause this ?
The board has one ...
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0
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3 pin ethernet module?
So basically I'm working on a project that uses an Atmega328 like on the Arduino Uno. I need to receive both DMX (with max485) and E131 (Not both at the same time, I'll decide which with a boolean in ...
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0
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How can I use Arduino Analog Uno pins as Digital pins? [duplicate]
How can I use Arduino Uno Analog Pins as Digital pins, So that I can Attach more components like sensors to the Arduino? My 13 pins are preoccupied and I want more.
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