Questions tagged [analogread]
A standard Arduino function for measuring the voltage on an analog pin via ADC.
349 questions
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Arduino DUE - I Have enabled A14, will this break anything?
I developed a quick custom PCB using the ATSAM3X8EA-AU as I wanted to use Arduino to program it as an Arduino DUE, I kept most of the schematic the same, however I used pin A14 pin 52 as an analog ...
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Pop-Up Headlight Management
I have a 90s car with pop-up headlights but I don't have the original headlight module. So I am trying to make one myself.
The idea is simple
1- I have a Master switch that keeps headlights UP ...
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177
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Arduino seems to be reading incorrect analog I/O. Am I doing something wrong?
I am using an ATTiny88 to measure temperature using a 470 ohm thermistor attached to port A3 on the Arduino.
The thermistor is attached in series with an 1870 ohm resistor connected to Vcc. At room ...
2
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120
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Non-blocking analogRead for Arduino Nano 33 BLE sense
I need an alternative to analogRead() that doesn't block the processor. I've managed to find a lot of solutions for this for other boards, but not something that's compatible with nrf5240 like the one ...
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Arduino Uno, does a lower Aref voltage work well for measuring current? without increasing ADC integral non-linearity
I want to measure current using a Arduino Uno and use a very low resistance of 0.1Ohm or lower for the shunt resistor to measure the current(to reduce power waste and heat generation),
as a result ...
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ESP32 Shows Incorrect Input Voltage From Analog Pin
I have an esp32 WROOM-32 connected to a MQ9 gas sensor to GPIO35. Both are powered separately. measuring the output from the sensor directly using a multi-meter shows a constant reading of 0.145 V but ...
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How does actually arduino measure voltage?
I am not interested into the AnalogRead() part, but rather on how he converts 5 or 2 V into a number between 0 and 1023. How does it practically do it to convert the voltage level into a number or ...
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How to turn LEDs based on voltage readings?
I am trying to turn LEDs in an LED bridge based on the voltage reading from a power source. when the Voltage is zero nothing is ON and then the LEDs gradually turn ON as increase the voltage connected ...
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181
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Inconsistent results when reading input looking for spike patterns
I'm writing a library that will interface with a control unit on a refrigerator compressor pump (QDZH35G). One of the features of the control unit is that it can detect what problems it's encountering ...
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Why does analogRead(A0) deliver different Values when called in a library file vs calling it in the sketch directly
I wanted to write a library representing a sensor to later on have an array of sensors.
I generated a file MoistureSensor.h:
#ifndef MoistureSensor_h
#define MoistureSensor_h
#include <Arduino.h&...
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Issues using mini microphone module off AliExpress
I have been trying to get a mini microphone module with an inbuilt microphone module I got from AliExpress to my Arduino to confirm if it is working. It was a four pin microphone with pins labeled V, ...
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Copy Uno Analog Input Configuration To ESP32
I started a project using the arduino uno and as a challenge I'm attempting to make it work with the esp32 but I've run into a roadblock. I may not describe it in proper terms, but I noticed that the ...
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Analogue input spikes
i have a project where i read two analogue inputs from two sensors and a pro Mini. I have some spikes in my readings that are present when i'm powering the system using a powerbank step-up module. ...
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50% duty cycle PWM signal with calculated frequency
#include <PWM.h>
int led = 9;
void setup()
{
InitTimersSafe();
Serial.begin(115200);
Serial.println();
variable_freq();
pinMode(A0,INPUT);
}
void variable_freq()
{
while(true)
{
...
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1
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Using 1.1Vf to read stable battery voltage and sensor voltage
After several tries, i was successful with reading stable battery voltage using internal voltage reference of 1.1v, now the issue i face is that i cannot read stable sensor voltage, could you please ...
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Reading constant battery voltage and using the obtained value in sensor formula
there i am working on a project in which my system is connected to 3.7v~4.2V lithium battery, I have to read constant battery voltage irrespective of the current battery voltage and to do that I am ...
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1
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Carbon dioxide sensor MG 811
I am using MG811 carbon dioxide sensor with ESP8266 module. CO2 values is being read inside closed room. The value comes around 400 ppm. Using CO2 generator does not make increase in reading. Checked ...
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1
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600VDC measurement with Arduino (voltage divider)
I need to detect quick (~200ms) voltage drop, so I am thinking of making an oscilloscope with Arduino. Problem is - can I reliably read 600V DC voltage and what resistor values should I choose for ...
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How to work with a pulled high input pin where it needs to read a value from an analog sensor?
I have a small ESP32 module, that has some in-built features, like a TFT, and has few available pins for general use.
It has some input only pins (GPIO36 to 39) that are used by buttons soldered in ...
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Code not checking for updated sensor values after connecting to firebase?
I am using a project with an MQ138 sensor and want to push the real time sensor reads to firebase. Currently, the wifi/firebase part and sensor part work fine separately. The code connects to wifi and ...
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Arduino Mega, 6 push buttons for each analog input (A0-A9) - closing one results in reading by other
On day to day basis I'm more of a high level programmer, with little electronics knowledge, apologies in advance if I lack some nomenclature or basics. I communicate with my Arduino Mega via firmata, ...
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IF statement to run even if the requirement isn't met anymore
I have built a flasher for the headlamps on my race car. Whilst it works when I hold the switch down, if I release the switch and the circuit is closed my IF statements requirements are no longer met ...
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Arduino Uno Analog pot values are not smooth
I have tired Arduino smoothing example but mine analog value are not staying constant even when I don't rotate the potentiometer. I am mapping the values from 0 -> 1024 to 0-> 100. I have tried ...
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Measured voltage higher than AREF
What happen when a voltage measured by analogRead() is higher than AREF voltage?
Example: AREF = 2.5V AO = 3.2V
What is the maximum voltage ?
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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 ...
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Why do I get different times when using analogRead() inside while loop?
I have the following code which checks the latency of another board.
int triggerPin = 13;
int dataPin = 9;
int ejectorPin = A0;
unsigned long t_start = 0;
unsigned long t_end = 0;
...
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1
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1
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341
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NodeMCU dev board shows 13 for ADC when grounded - why?
I have a NodeMCU 1.0 ESP-12E development board. Trying to hook up a LM35 to measure temperature. For that I need to use the analog pin A0. However it seems my sensor is out by about 4C. I traced ...
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432
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Analog UV sensor displaying incorrect values in serial monitor (GUVA-S12SD)
Using Arduino Uno and a GUVA-S12SD sensor (https://www.adafruit.com/product/1918).
Here's my circuit. 5V into sensor+, GND into sensor-, A0 to sensor out.
Here's my code:
void setup()
{
Serial....
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1
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2
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206
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LCD TFT 2.4"" changes the values of analog read of Arduino Mega
I have a Arduino Mega with LCD TFT 2.4"" with reading 5v signal on A8 pin (Arduino mega pin) from a raspberry pi (just to test). They are grounded together. When the Arduino is without the ...
1
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0
answers
311
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I'm getting really unstable analog values with my B103348 joystick
I'm trying to make my B103348 joystick control a DC motor but I'm getting very unstable values from it specifically when the y axis is at 0. This is what my Serial monitor shows...
0,
21,
21,
21,
0,
...
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consecutive analogRead()
Has anyone noticed that if calling analogRead() in a consecutive way that the value drops by a bit as opposed to just doing a single read?
And is this to be expected?
I am using a Seeeduino XIAO.
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Arduino Multiplexer Input voltage per pin not decoupled
I am very new to electronics (software engineer background).
I want to send an analog signal (5V) to one/many input wires. The input wires are connected to a 16 channel mutiplexer.
My arduino then ...
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1
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How to reduce AnalogRead noise?
Currently trying to read off values from a photodiode through analogread. It's constantly so noisy and I thought it might be something wrong with my low-pass filter, but I decided to just connect a 1....
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Analog read not working while using WiFi
I have an ESP32, the current program running on it uses WiFi but, if I use WiFi and Analog read at the same time, Analog read does not work.
Why does this happen and what's the way around it?
Hardware ...
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Can I test if something is connected to analog pin?
In my sketch I have a potentiometer connected to A0. The value of the pot is used to adjust the speed of a connected item.
I have set the speed to have a default value, but doing analogRead() on a ...
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0
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Pyfirmata util.Iterator causes serial communications issues with more than one Arduino
I'm using two Arduino Megas in a project to read data from a bunch of analog sensors and then output PWMs on digital pins according to their value. These analog signals are also being plotted on a ...
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Problem with floating of AnalogRead
For a university Lab course i have to realize a UPS unit with a internal LiPo battery . The unit uses as battery charger a buck converter
I have only a problem with the battery charger (buck converter)...
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81
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Math on analog read wrong result
I'm trying to execute a math of analog read but I get some weird result.. I searched about int and floats but didn't understand..
My code is :
#include <SevSeg.h>
SevSeg sevSeg;
int bitsChange ...
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3
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952
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Inaccurate voltage readings on an esp32 as opposed to multimeter
I am working on detecting the amplitude of a signal coming from a guitar pickup. I am using an esp32 and an LM386 module for amplifying the signal.
I get quite stable readings with a multimeter, but ...
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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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Is defining a function improves speed rather computing average for each analog input separately
My Arduino controller reads data coming from four different sensors. After the data is read, I individually compute four input average values. I understood that I am having the same lines of code ...
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Why AnalogRead shows value (395) when its on HIGH State ? why not shows 1023 when its high State
I Took a output from ESP8266 and Connected it with Arduino Nano Analog input A0
i use BLYNK app to on/off D0 pin in ESP8266 , and i connected ESP8266 D0 pin with Arduino Nano A0 analogPin.
when ...
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0
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ESP32 reading analog 2.4Ghz
Is there a possibility to analog read on the 2.4Ghz band to just read how much activity is in the presence of your device? Not parsing the messages but just listening to how strong of a signal you are ...
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SEN0114 moisture sensor low max reading?
I am using the following SEN0114 moisture sensor with an ESP32: https://datasheetspdf.com/datasheet/SEN0114.html
How come when submerged in water I only get a reading of ~2500? Should this not read ~...
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443
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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 ...
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Arduino measuring high-voltage electric fence
I would like to know if someone has experience with measuring high voltages using an Arduino.
I know you can use resistors to lower the voltage, however.
I want to be able to measure the pulses of an ...
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Time signal. Determine the presence of pulses and their duration [closed]
I want to detect the exact time signal from an FM radio station. The signal is transmitted in the form of 5 short pulses and one long one. My task is to determine the presence of a pulse in the audio ...
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Attiny : Is it possible to analog read on PB1?
I'm trying to read an analog input on the Attiny85 physical pin 6 (PB1, PWM), but analogRead(PB1) always returns 1023. Is it even possible to use analogRead on this pin?
I'm fairly new to this so ...
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0
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65
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Phantom reading
my project is to control led diode and dc motor, test shield buttons, and check system run time.
Testing buttons and run time i have done.
Deal is with led and dc motor control.
I'm getting phantom ...
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How to read an analog value on ESP32-CAM with the SD card reader enabled?
I use an ESP32-Cam module for a project for which I need both the SD card and the cam. According to this page, the only pins that are not in use by either the camera or the SD card reader are GPIO0, ...
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