Questions tagged [analogread]
A standard Arduino function for detecting the voltage on an analog pin via ADC.
279
questions
0
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1answer
27 views
Why does the reading on the ESP32 read max, when the reading on UNO read accurately?
I have a 'Capacitive Soil Moisture Sensor' hooked up to my Uno.
Very simple code. AnalogRead(MoistureSensorPin);
This will return a differing value that I can work with.
When applying the same code ...
0
votes
1answer
38 views
When does the ADC take the reading?
I'm experimenting with the "2 pin capacitance meter" and trying to make it more accurate. Currently I've made the Arduino read 62.5 ns intervals but this means the time for the ADC to read is taking ...
0
votes
1answer
44 views
ADC register always returning high
Regardless of whatever voltage at A0, the software is always returning high (1023)
volatile unsigned char* ADmux = (unsigned char*) 0x7C;
volatile unsigned char* ADCSRa = (unsigned char*) 0x7A;
...
1
vote
1answer
67 views
Measuring 12 V via voltage divider: choosing the right resistors
I want to measure a 9 V battery via one of the analog input ports of my Arduino Nano. From all the schemes of this great answer, I choose the simplest one, the voltage divider. Assuming the maximum ...
0
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1answer
49 views
Variable sets to 32767 - MATLAB Arduino
I am running out of ideas of what may be causing this problem, and I would appreciate some help identifying anything I am overlooking.
Quick Problem Summary
A variable gets set to 32767 quite often ...
2
votes
2answers
76 views
Noise on piezo analog read due to Arduino power supply
I am making a device that measures temperature and vibrations and records the values onto an SD card. It will be a standalone device.
The hardware used:
- Arduino Uno
- PCF8523 RTC clock
- MAX3186 + ...
0
votes
1answer
42 views
Specific ports on Teensy 3.6 not reading correct bit resolution using ADC library?
I have a basic circuit, where I'm reading analog values from 14 infrared receivers.
I set the bit resolution to 16 but specific ports are returning 10 bit values (from 0 - 1024) instead of 16 bit ...
2
votes
2answers
291 views
ignoring potentiometer value variations
I've got a 50k potentiometer connected to an Arduino Uno. The user should adjust the hue of an Adafruit NeoPixelStrip.
I've got the following code inside the loop function:
int hue = analogRead(...
-1
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1answer
21 views
Sound sensor's output stucks to high values when I include a delay in the loop function
I use Waveshare's Sound Sensor module.
I use this simple code to test the module:
As you can see, the problem is that when I have a delay in the program, once the analogRead is bigger than 10 (by ...
0
votes
1answer
36 views
Mapping values from analog input giving unexpected values?
Mega 2560
I am reading in values from 3 pots then mapping them to values between 0 - 255
#define REDPIN 7
#define GREENPIN 8
#define BLUEPIN 9
int red_pot = A0; // analog pin used to connect ...
0
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0answers
47 views
Temperature varations using ADS1115 and voltage divider to read 12v
I have an issue with reading battery voltages of three 12 volt batteries using an ESP-01 and an ADS1115. I have been graphing the measurements and the all of the graphs have a temperature component ...
0
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1answer
71 views
Noisy analogRead
I'm trying to read voltage using Arduino, here's the code:
float r1 = 99700;
float r2 = 10004;
float adc, voltage;
unsigned long analog;
void setup() {
Serial.begin(9600);
analogReference(...
0
votes
0answers
32 views
Strange cyclic errors in analogRead on Nano
I am trying to build an emergency shutdown of a gas valve based on the output of a smoke detector.
It basically measures the voltage on the buzzer of the smoke detector, and if high enough, changes ...
0
votes
1answer
30 views
Playing Audio from SD - Get VU, or audio waveform
I am using the library SimpleSDAudio to play a song from my SD card to an op-amp later in the circuit. I would like to take a sample from the audio pin (possibly with a Analog read) to power some ...
0
votes
1answer
35 views
Not getting any output from ECG sensor AD8232
I am trying for the beginning to run a simple Arduino code in order to test the functionality of the ECG sensor. What I am getting on the output are some random values around 600 or around 200.
I ...
0
votes
2answers
53 views
Buzzer interfere with thermistor reading
This is how i wired the thermistor and buzzer:
simulate this circuit – Schematic created using CircuitLab
And the code:
#define RT0 10000
#define B 3977
#define R 10000
float RT, VR, ln, TX, ...
0
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0answers
27 views
ESP32 PH probe analogRead Value Alternating
i got an ESP32 WROOM32-OLED with a PH-Probe hooked up to it (PIN39).
When i short the probe interfcace to get a PH07 reading (connecting the middle of the probe interface to ground) i get really ...
0
votes
1answer
22 views
Increasing range of a DC-offset signal (software)
I am trying to read a signal with a DC offset of 511 (as seen by the ADC). The signal's tiny with regards to the offset, and I'm feeding it to a library that does a Fourier transform on it. It comes ...
0
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0answers
49 views
Can HC-05 Continuously Stream data and read data at the same time?
I am trying to have my Arduino Stream an Analog Signal using Bluetooth Module (HC-05) while being able to read commands from another Micro-controller using the same Bluetooth Module.
Currently, I am ...
1
vote
2answers
55 views
Why do all analog pins measure the same value?
I measure 2 analog pins: A4 and A5. The A5 pin is connected to another Arduino's digital out (through a 10k resistor) which has a simple program: 5ms on and 100ms off. The A4 pin is not connected ...
0
votes
1answer
40 views
Using case statement with IR emitter reciever
I am trying to use two "infrared obstacle avoidance modules" to work with the following sketch. From all my research, I believe, a case statement is my best option because, (I understand) the sketch ...
0
votes
2answers
30 views
Calculate statistic in EEPROM
I've search on how to do statistic calculation in EEPROM, but non related.
The data that I stored in EEPROM is body temperature.
Currently I stored the data using float.
Below is my code for data ...
0
votes
1answer
88 views
analogRead Function AC Voltage Reading Capabilities
Usually when you sense AC voltage, you get a sinusoidal waveform. However, for AC voltage sources, Arduino analogRead ( ) only presents positive voltage values. So what's basically happening? Is it ...
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1answer
59 views
AC Voltage Sensing using Arduino Uno
Is it possible to sense AC Voltage using analog input for Arduino Uno or can it only read DC?
I mean I've tried connecting an AC voltage source to analog and I'm reading some numbers. However, I don'...
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1answer
96 views
analogRead() output oscillates even though the pin is grounded
I'm using Arduino Micro to read from 5 flex sensors and display the corresponding angles to the Serial monitor. I am currently having quite some problems with the oscillating values I am getting from ...
0
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1answer
66 views
Help combining digital and analog code in arduino programming
So I'm making a device that does 3 things,
Measures frequency of an audio signal through a microphone
Checks whether there is a weight placed on a pressure pad (my pressure sensor works through the ...
1
vote
1answer
29 views
Electret microphone board strange offset using Arduino
I'm experimenting with an electret microphone, specifically this one. I put it on my scope and I see what I expect - a really small voltage, typically under 20mV, that varies appropriately with sound....
0
votes
2answers
192 views
Value read is not changing while rotating pot in arduino?
I am trying to read voltage using analogRead in Arduino Uno from a voltage divider circuit consisting of 1k resistor and 10k pot. The Pot used is bourns 3296. The values obtained only range from 1011 ...
0
votes
2answers
61 views
How to drive Arduino UNO as a counter triggered by 555 timer's output (astable mode)
I have an Arduino Uno and a 555 timer configured to astable mode.
What I'm trying to do is to program my Arduino to increase a "counter" variable (counter++) everytime it gets triggered by 555 timer'...
0
votes
1answer
75 views
How to convert digital signal to analog value
I have spwm output from arduino, and when i read on analogread it shows only 1023 and 0, because it is digital signal.
Is there any way to convert these spwm value into analog value reading
0
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0answers
21 views
Why UDP does not work after analogRead() on esp8266-12N module? [duplicate]
Consider my loop() in Arduino be:
void loop(){
for(int i = 0; i<100; i++){
Value[i] = analogRead(A0);
delayMicroseconds(62);
}
//delay(2) //when I use this line esp8266 works properly
...
0
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1answer
61 views
Analog reading with noise - Arduino Uno VS ESP12e
I was testing analog output from a microphone (Max9814) with an Arduino Uno, which came with nice results. The output provided by the microphone is converted into sound and is loud and clear.
Setup: (...
2
votes
1answer
135 views
Ardunio Mega/ATmega2560: Using Port F or K for both analog inputs and digital outputs
On an ATmega2560, can ports have some pins used for analog inputs but others as digtial i/o? Specifically, I only need to use 3-5 analog inputs but have many digital inputs. I would like to use the ...
2
votes
0answers
246 views
Measuring Amplitude/Frequency of sound
I need to read an analog signal at about 500-1000Hz for at least 5 seconds.
I've a battery powered microphone wired into an analog and ground pin on my arduino and am trying to measure the frequency ...
0
votes
1answer
95 views
making power harmonics analyser which will measure the amplitudes of the fundamental and its multiples (like 50hz, 100hz, 150hz,200 hz,…) there are)
i have been intendng to make a power frequency harmonics analyser which will measure the amplitudes of the fundamental and its multiples (like 50hz, 100hz, 150hz,200 hz,...) there are examples for ...
0
votes
1answer
92 views
Measure small capacitances with ATtiny85 (Digispark board)
I have successfully run the code provided here on an Arduino Nano. If nothing is connected, it will output a very small capacitance (~ 1 pF).
Then I tried to migrate the code to the ATtiny85 (using ...
0
votes
2answers
160 views
What data type are the analog pin labels (A0, A1, etc)?
Arduino Mega
I would like to have an array containing analog pin labels something like...
int analog_pins[] = {A0, A1, A2, A3};
int num_analog_pins = sizeof(analog_pins) / sizeof(analog_pins[0]);
...
1
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1answer
50 views
How to read analog pins from a second Arduino
I've run out of analog pins on Arduino Uno and don't have time to order new parts. I've heard you can connect two Arduinos and I have access to another UNO. If I did that, could I read the analog pins ...
0
votes
2answers
91 views
Arduino analogRead fluctuates from sensor unless USB connected
I have an Arduino connected to a 4-20 mA sensor through a current to voltage converter. When connected to the power supply the sensor reading fluctuates, as soon as I also connect it to a USB port it ...
0
votes
1answer
45 views
Can I read using an analog pin on an arduino Mega whether or not there is a high (5v) voltage on a wire from another board's digital pin?
I am making a peer-to-peer network of initiating devices and a common hub, which controls most of the hardware. It sends a number over Serial to Mega's Serial1 (Mega's Serial is used for communicating ...
0
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2answers
129 views
Would a 100KΩ resistor connected to ground pull an open analog line down to 0
I have a project that has a photoresistor wired into a voltage divider and connected through a 3.5mm “stereo mini plug”. When nothing is in the mini plug, the analog line is an open circuit, and ...
0
votes
1answer
32 views
How to map integer values and round to a count of tens/thousands?
I'm mapping a potentiometer from 0-1023 to 1000-120000 (1 sec to 2 minutes) for a timer, like:
maxDelay = map (pot2, 0, 1023, 1000, 120000);
Both variables are integers. Now I would like to convert/...
0
votes
1answer
260 views
How to re-construct audio from series of analog integer input?
I'm trying to learn how to stream audio from the A0 pin of an ESP8266 NodeMCU board via UDP socket connection over to another windows computer that uses pyaudio to play it. At the moment, all I get ...
1
vote
2answers
298 views
AnalogRead value constant for a varying voltage (for LED brightness variation)
Having the 11~ pin on OUTPUT mode that delivers a varying voltage (from 0 to 5 : 0 to 255).
and the A0 pin on INPUT mode to read the voltage, I find that the value read by A0 being either 0 or 1016 ...
0
votes
1answer
207 views
Analog output gives a close range of values
I try to get a good range of values from VMA309 sound sensor.
However, when I connect it properly it gives me a range of values +/-5 like below. The documentation says it should give numbers ...
0
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2answers
2k views
Reading Multiple Analog Input Pins
I am having a bit of trouble trying to read multiple Analog Input Pins (A0 and A3, in this instance). I am using a Pololu A-Star 32U4 LV Robot Controller (https://www.pololu.com/product/3116), and am ...
0
votes
1answer
91 views
Cannot get esp8266 - 12 wifi module to always read analogRead incoming voltage accurately
So I have and arduino uno that is firing an output on pin 8. This code is not in this file just to be clear. From there Im taking that output and using it to fire pin 0 on the wifi module. Im using ...
0
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0answers
37 views
Differing behaviour from Arduino Nano when plugged into laptop vs power source
Well here's a weird one. I'm monitoring a mic on an analog pin of an Arduino Nano and using the variation in voltage to control and LED.
When plugged in to my Laptop (USB 3, 500ma available, the ...
0
votes
1answer
101 views
Reading analog value while generating PWM signal
I'm trying to generate dim two LED strips simultaneously by generating two PWM signals based on potentionmeter value. The pot sets how bright each of the LED strips will be. To drive this I'm using ...
0
votes
1answer
312 views
Unstable analog sensor readout
I have the Arduino Uno (non-original replica) board, general SPI lcd, and GUVA-S12SD analog UV sensor module.
The board (powered via USB) reads the data from the analog pin 0, converts it to voltage (...
