Questions tagged [adc]
Analog Digital converter
122
questions
0
votes
1answer
36 views
Measuring Battery level with ADC already in use
I have NodeMCU v3 with ESP8266 and I am running small project where I am measuring the input from IR phototransistor via ADC pin (A0) and everything is working flawlessly.
But now I want to transfer ...
0
votes
1answer
28 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 ...
0
votes
0answers
23 views
Communication between arduino nano and MCP3424 over I2c pt. 2
I'm am completing a project of mine that uses an MCP3424 i2c 18bit ADC and an arduino nano to measure temperature with an NTC thermistor but am having trouble with the arduino wire library. This is my ...
0
votes
1answer
38 views
Arduino vs 12bit ADC
12bit ADC will give us about 1.2mV per step:
5 / 4096 = 0.00122
But if we give Arduino a 1.2V voltage reference we get 1.1mV per step:
1.2 / 1024 = 0.00117
Does that means Arduino can be more ...
0
votes
1answer
35 views
AD7476 adc and SPI
I'm trying to understand if I can use the AD7476 with Arduino and SPI:
datasheet
My rough idea is that I should put CS low, then read two bytes using SPI.transfer() twice, and then bring CS high ...
0
votes
2answers
47 views
Measuring current directly with Arduino
Is it safe to measure current like this as long as measured voltage drop don't exceed 5V? I'm asking this because in almost all current sense circuits they used an opamp in their design.
Do I need a ...
0
votes
2answers
76 views
Arduino 10bit ADC is not accurate?
I'm reading the voltage with voltage divider:
simulate this circuit – Schematic created using CircuitLab
| Arduino is connected to both USB and a 9V adapter.
float r1 = 100000;
float r2 = ...
0
votes
1answer
54 views
ADS1115, ACS712 and ESP8266
I have an ACS712 (5v sensor), an ADS1115 (5 or 3.3v) and an ESP8266 board (3.3v).
I know I can't directly use the ACS with the ESP without a voltage divider on the analog pin. So I figured I could ...
0
votes
1answer
51 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
1answer
57 views
How do I convert this program to assembly from c++
I am trying to implement a program in assembly code for an Arduino UNO. A potentiometer is used on an ADC pin for variable time (t). LED1 flashes for t seconds, then stays on for t seconds, then goes ...
0
votes
1answer
50 views
Using Arduino to Record analog signals with SPI ADC + Sampling Rate Issue
I am using Arduino UNO to Read 8-channel, 24-bits resolution Analog signals using ADS1299 Analog-fornt-end. ADS1299 use SPI interface to talk with Arduino. Currently, I can record the analog signal ...
0
votes
0answers
52 views
Attiny ADC at voltages less than 5v
So, this is peculiar. I am using an ATTINY84 chip as an i2c ADC converter (there are reasons why I'm using this rather than a dedicated chip, but that's not really relevant), and I've noticed that I ...
1
vote
2answers
47 views
Sampling stereo audio at greater than 40 Hertz using arduino
I am working on a project to make a speaker with reactive lighting. I need to be able to sample stereo audio at a decent rate for songs. The audioRead () function can do about 8 kHz and I have heard ...
0
votes
0answers
33 views
Combining ADC IRQ with SPI peripherals results in SPI not working
I'm working on a pet project that requires ADC, SD card (SPI interface, SdFat library) and a display in the future (also SPI).
I have put together a piece of code that initializes ADC at the highest ...
1
vote
1answer
88 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 ...
-1
votes
1answer
25 views
Controller freezes
I am using atmega 2560 as main(master) controller and other 5 salve 2 atmega 8 and 3 atmega 328p, there is two device with analogue output connected to main controller atmega 2560 through ads1115 ...
1
vote
1answer
26 views
How does use an arduino like a A/D converter for convert 3 analogue signal from 3 poteciometer to a raspberry?
I am developing a control system in my raspberry, but i have the problem that it doesn't have any analogue port, so if i use an arduino to convert de signal from analogue to digital and after send ...
0
votes
2answers
40 views
the code and the actual output didn't match
i want to make the stuff, which the output is written from the analogread, but when the A3 == HIGH, the output pin 9 is used, but when the A3 == LOW, the output pin 10 is used, and when i simulate it ...
0
votes
2answers
79 views
How to get average of 16bit ADC readings?
I have an Adafruit ADS1115 analog-to-digital converter, configured in single ended mode. I want to average over 3 sensor readings to increase the reading stability.
//initialize variables
int16_t ...
2
votes
1answer
111 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 ...
3
votes
1answer
173 views
SPI Connections to DAC [closed]
I'm hoping to construct a feedback loop for a laser using an Chipkit UC32 and an analog-digitial converter ( the one of I have is an AD5780 evaluation board). I've been reading through Digilint's SPI ...
0
votes
0answers
134 views
AD7606 DAQ and datalogging
I'm making a Data Acquisition System for force impact usign an AD7606 from Analog Devices, an Arduino DUE and a load cell. I already tested it following this guide an making the proper changes for ...
0
votes
0answers
239 views
Arduino Mega and ADS1256 board
I found code for a Teensy board and now I added just digitalwriteFast library to code and changed port to SPI for Arduino Mega. And now I get just one number out:
#include <SPI.h>
#include <...
0
votes
0answers
100 views
Using TCA9548A to read 30 ADCs
I want to read 30 differential ended analog sensors.
Using ADS1115 16 bit this is possible, but we end up having only 4 address on I2C, so i chose TCA9548A breakout board with 8 I2C multiplex channels,...
0
votes
0answers
26 views
AK4524 with Arduino
I have some AK4524 ADC/DAC chips from an old M-Audio Delta 10/10 sound card in my hand.
I would like to use them for precision sensor reading and voltage generating with a arduino nano.
My ...
0
votes
1answer
57 views
Voltage meter ADC + serial: Bytes lost during communication
I want to make a simple digital voltage monitor. So I have a sketch:
void setup() {
Serial.begin(115200);
}
void loop() {
int val = analogRead(A4); // read the input pin
val = 1;
byte ...
0
votes
1answer
36 views
How to check whether my arduino-mega ADC is sampling correctly?
I have a code which samples the given input signals with sampling rate 256hz. I plotted the graph of FFT and was able to see the peaks at the expected frequencies.But I would like to know whether my ...
0
votes
1answer
140 views
Getting incorrect output from ADC over SPI in Arduino Uno
I am trying to read data from an ADC ADCS7476 (datasheet) using SPI on Arduino Uno. I am using the following code to read the data from the ADC and printing it on serial monitor. However, the code is ...
1
vote
1answer
55 views
Anomalous behaviour of ADC, digitalWrite and floating point operations
I'm trying to analyse mic (A0) input, calculate certain spectral lines with Goertzel algorithm to detect a number encoded by DTFM and display it with 8x8 matrix display (max7219 driver).
The code ...
0
votes
1answer
123 views
Running ADC triggered by TIMER1_COMPB
I'm trying to run ADC on channel 0 triggered by TIMER1_COMPB.
Everything seem to work ok but basic arithmetics is not working and variables inside ISR and even main loop don't get updated (x == 2 all ...
1
vote
1answer
241 views
Trouble configuring Arduino Due SPI to ADC
I am having trouble configuring Arduino Due SPI to an AD7490 ADC.
Here is how I have the pins connected:
+3.3V > 7490 pin 22 Vin
+3.3V > 7490 Vref
DUE CS (8) > 7490 pin 20 SS - slave select)
DUE ...
0
votes
1answer
107 views
ADC noise when sharing ground from external supplies
i have resistor based sensor, when i test it using arduino connect to PC using serial monitor without sharing ground to other circuit it has a nice value between 300-650 in adc range and the error/ ...
1
vote
1answer
107 views
Arduino Uno ADCH register stuck at 255 when read from ISR
I'm working on a project that will essentially become an oscilloscope in the long run. I am following this guide. My code is uploaded here for more reference.
In my .ino file I have called functions ...
0
votes
2answers
69 views
Stacking adc's when making an midi controller ( lots of potmeters)
I'm making a midi controller with the Arduino uno. It contains approximately 50 analog inputs with potentiometers. I have enough MCP3008 adc's here but I have no idea how I connect 2 or more adc's to ...
0
votes
1answer
115 views
Due: Write to digital pin when ADC is running
I have a problem writing to a digital pin on Arduino Due while my ADC is running.
I have the following code:
#undef HID_ENABLED
// Arduino Due ADC->DMA->USB 1MSPS
// by stimmer
// from ...
0
votes
1answer
190 views
Waterlevel sensor disrupts PH reading
I have a water level sensor and a PH sensor connected to my nodemcu via an ADS1115 . When I insert only the PH sensor into the water then everything works fine. But when I insert the waterlevel sensor ...
0
votes
1answer
99 views
If I use a biasing circuit for a signal going into an analog input pin, will it affect the ADC operation?
If I have a single 100Hz AC signal biased by two 1 M-ohm resistors (as per schematic below), and then output to an Arduino UNO analog input pin, with the UNO sampling at around 1 kHz using delays, ...
5
votes
2answers
631 views
What will happen if I set ARef to 3.3V and try to use adc connected to 5V
What will happen, if I try to measure voltage higher than ARef?
For example, my ref is 3.3V, and I try to measure 4.5V. Will it damage adc?
1
vote
2answers
166 views
How to set sampling rate for digital pin input? [closed]
I have an ADC that have sampling rate up to 40 MSPS, but i use 8 MHz clock so it will be 8 MSPS. The board used is arduino nano. The problem is i have to sampling it just 2 MHz (because the capacity ...
0
votes
1answer
79 views
How to decrease adc accuracy?
I read in this atmega328p datasheet the following on page 308:
From sect. 28.4:
By default, the successive approximation circuitry requires an input
clock frequency between 50kHz and 200kHz to ...
0
votes
1answer
371 views
Interaction between Analog Pins when measuring a DC voltage- a common issue? [duplicate]
Just set up a replacement "Piduino" - a RPi3 connected by USB to an Arduino Uno. The previous one was the victim of a Diet Big Gulp - spilled on the voltage divider breadboard. Whoops. The tiny ...
0
votes
1answer
179 views
Repairing Analogue Inputs on Uno?
After a long afternoon, chasing a fault on my project, I've come to find that I've damaged 2 out of the 6 Analogue Inputs. Their ADC reading doesn't display 0 when grounded, nor a known ADC value from ...
0
votes
2answers
2k views
Measuring Lithium ion cell voltage used to power Arduino via a boost module
Can I measure lithium ion cell voltage with Arduino ADC which is used to power the same Arduino through a boost module (XL6009)? The output voltage of boost module is 9 volts.
0
votes
0answers
837 views
ESP8266 ADC read analog
I have a 24CL256 external EEPROM, to which I wish to write 30,000 bytes of 8-bit data, reading from the built-in ADC of an ESP8266.
Here is my code:
void setup() {
Serial.begin(115200);
Wire....
2
votes
1answer
3k views
ESP8266: system_adc_read_fast() always give 1024 as output
I need to use system_adc_read_fast (uint16 *adc_addr, uint16 adc_num, uint8 adc_clk_div) to get a sampling rate close to 100ksps. And I am able to achieve that using adc_clk_div = 32.
However, when I ...
1
vote
0answers
795 views
Where is the definition of system_adc_read() in the esp8266 Arduino code?
Where is the definition of uint16 system_adc_read(void) in the esp8266 Arduino code?
I can see it being declared in Arduino/tools/sdk/include/user_interface.h, however there seems to be no definition ...
1
vote
1answer
1k views
Read analog signal over the SPI bus using MCP3201 ADC and Arduino Uno
It is possible to use the SPI bus when the Vref of MCP3201 ADC is 2.5V?
On the setup i just finished, I used two linear regulators: 5V -> 3.3V to power the MCP602 op-amps and MCP3201 ADC, and another ...
2
votes
4answers
7k views
what is arduino adc reference?
I'm using arduino for the first time and don't really understand what am I suppose to plug to the ADC refernce PIN... or if I even have to use it while plugging analog sensor to the arduino,
thanks!
2
votes
2answers
427 views
Lowest voltage applicable on AREF pin on Uno and Mega
I need to measure an Analog signal in the range of 5-30 mV.
Naturally, using the internal default 5V reference leads to very poor measurement resolution. I would like to use the capability to use an ...
0
votes
1answer
130 views
External ADC reference when using MATLAB support package for Arduino
I am using the MATLAB support package for Arduino.
However, I need to configure the ADC reference to external. MATLAB documentation doesn't really explain how to do this?
Is there any way I can use ...
