Questions tagged [digitalwrite]
Write a HIGH or a LOW value to a digital pin.
50 questions
2 votes
2 answers
863 views
How can I stop digital pins from floating at reboot?
I've got a LattePanda 3 Delta, which runs windows on its main processor and an Arduino sketch called StandardFirmata on its coprocessor. It's connected to a lock, which locks at HIGH and unlocks at ...
- 21
2 votes
2 answers
403 views
Can I use SPI-related pins as a Digital Output?
I am trying to use an esp32 (NodeMCU-32s) as a ringlight controller for my camera. All it should do is sense when an input pin goes low (the camera's output connects to ground when the shutter goes ...
- 21
0 votes
1 answer
471 views
LED doesn't completely turn off with digitalWrite(led, LOW);
When I was testing out a program I found a strange behavior of ESP8266. LEDs don't turn off completely in the first digitalWrite(led, LOW), just the brightness of the LED goes down, but it does turn ...
- 73
1 vote
1 answer
187 views
Fast digital IO
I have a device programmable via an 8 bit digital parallel bus. I would like an Arduino to translate from a parallel 4 bit output of an existing device to 8 bit by intentionally reducing the ...
- 121
1 vote
2 answers
118 views
How to increase pinout switching?
Consider this code: void loop() { digitalWrite(pinTest, HIGH); digitalWrite(pinTest, LOW); } On an Arduino Mega 2560, running 16MHz (=0.06us), I would expect the width of the pulse to be ...
- 195
0 votes
1 answer
214 views
How to control PWM and digital pins at the same time over ethernet in arduino
I am using Controllino Maxi. It has an Arduino Uno inside it. I am trying to control the PWM pin D0 and digital pin R0 via python code. Below is the code I have upload on arduino: Arduino Code: #...
- 183
0 votes
2 answers
464 views
Read Digital Input from Arduino Pin defined as OUTPUT
I'm working on a Home Automation Project. I can turn on-off ESP32 pin from Alexa and Google Assistant Successfully now. What I need help is with a way to read if the AC supply is ON/OFF on the Arduino ...
0 votes
1 answer
170 views
digitalWrite giving different output voltages between programs
I'm using an arduino uno R3 for lighting a few LEDs in response to coputer control. I've written two programs, the first to try an Object Oriented style, and the second to split up the code into more ...
- 3
2 votes
0 answers
204 views
Arduino Micro digital output pins floating / high Z
so i recently got an arduino micro for a project needing the control of two stepper motors with the A4988 driver. previously i was prototyping on an arduino uno and everything was working fine, but on ...
1 vote
2 answers
406 views
Why analogRead's value decreases when I decrease the value of resistor?(I use digitalWrite(high) to positive terminal of resistor)
Basically, my circuit contains only 1 resistor(like the basic LED circuit). I tried to know what is the actual voltage of digitalWrite(High). I don't understand why the value of analogRead does not ...
- 13
0 votes
1 answer
3k views
Random "Compilation error: Error: 13 INTERNAL: exit status 1". No clue how to resolve or even what causes this error
I am a beginner with Arduino. I have a program that is intentionally simple. The code refuses to compile, spitting out the error Compilation error: Error: 13 INTERNAL: exit status 1. I have gotten ...
- 111
0 votes
1 answer
122 views
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 ...
- 1,288
1 vote
0 answers
150 views
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 ...
2 votes
1 answer
443 views
analogRead() doesn't read more than 500Hz
I connected a wave generator to the analog pins to read the frequencies of the waves generated. I used different frequencies of sine waves with a minimum of 0V and maximum of 5V. Whenever the voltage ...
- 121
-2 votes
1 answer
160 views
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 ...
- 127