Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [arduino]

Be sure to use the Arduino Stack Exchange for questions that are more Arduino and less electronics.

0
votes
1answer
42 views

Can I connect an Android smartphone to an Arduino Uno?

I'd like to connect my main Android smartphone (it's a ZTE Blade X) to my Arduino Uno. My main reason is I'd like to use the camera on my phone as a sensor for the Arduino, for various projects. Is ...
-4
votes
0answers
36 views

Problem with 74hc595 output pins

i recently bought a 74HC595 shift register and just wanted to test it to see if working but i encountered some problems with output pins, in my code below it receives user number from 0 to 9 and ...
4
votes
6answers
7k views

What is going wrong in this circuit which supposedly should step down AC to arduino friendly voltage?

So I'm using this circuit but when adapter output is disconnected and only midpoint terminal of the transformer is connected the Arduino input pin reads some mV. mid point reads perfect 2.5V. What am ...
-1
votes
0answers
24 views

Don't able to program ATmega2560

I have developed custom PCB based on ATmega2560 microcontroller. I'm not able to upload code to ATmega2560. I'm using USBasp programmer and ProgISP to upload hex file. Programmer and ProgISP are ...
-1
votes
0answers
23 views

why L298N driving the motors properly on battery but not on adapter?

I am using Arduino, l298n, adapter(12v,2A) to drive the motor 12v,200rpm when I test the L298N by simply making high and low using jumpers the motor works fine but when I connect the jumper to the ...
0
votes
1answer
39 views

Operating AD5780 EVAL Board Via MicroController

OK, so thanks in advance because I am new here. I am reading the AD57XX drivers here https://wiki.analog.com/resources/tools-software/uc-drivers/renesas/ad5780 and am struggling to understand how to ...
0
votes
2answers
48 views

How to mount four 6-wire 10V load cells on Arduino or Raspberry Pi?

I want to connect four 6-wire load cells (Tedea Huntleigh Compression & Tension Load Cell 300kg, 15V dc, IP67, product page and datasheet) into an Arduino or Raspberry Pi and get four independent ...
0
votes
1answer
93 views

Trouble turning on relay using PNP transistor

I am having problems turning on this relay: https://omronfs.omron.com/en_US/ecb/products/pdf/en-g6qe.pdf Using a transistor whose base is connected to a digital signal of an Arduino Nano. The ...
1
vote
2answers
46 views

op-amp outputs supply voltage on GND Signal

I am trying to use an op-amp (first time). I know the basic theory of its amplification circuits. To test I am using an Arduino Nano Microcontroller to create a Signal (0-5V). I want to amplify the ...
0
votes
0answers
46 views

Should I use Wifi or zigbee for remote stop go lights?

I'm working on a small project to make some remote stop and go lights, i would like to be able to easily add an extra Box to the system as and when i need it. The idea is to have red and green ...
0
votes
0answers
39 views

Arduino pin connection basic

In the Arduino Uno's basic manual, connections for fading led are given. They have connected led on breadboard. The positive of led is connected through a resistor to the pin no 9 (pwm) and negative ...
0
votes
0answers
28 views

my LM35 temperature sensor gives weird measurements, [migrated]

Board: esp32 I know my wiring is correct because I get data from the sensor, but the data is a bit weird. At 22 celcius I get 140, even though if I do the voltage calculation (* 0.473372) it still ...
0
votes
0answers
35 views

Video transmission using microcontroller [closed]

I try to stream video using a microcontroller. I tried Raspberry and it was expensive and boot time was very slow (which is crucial for my project). I didn't try arduino because I assume it wasn't ...
0
votes
1answer
50 views

Converting Pulse Sequence Inputs Into Separate Outputs

I'm trying to find the simplest way of accomplishing the following task: Convert 3 different pulse input sequences into one of 3 different output lines The image below explains the problem ...
-2
votes
0answers
36 views

What is the best choice of rechargeable battery for an arduino pro mini + SG90 + EMG sensor? [closed]

So, I am building a project that requires that an Arduino Pro Mini read out a value off of a DFRobot EMG sensor 10 times a second and then, when the threshold value is exceeded(approx. once every 5-10 ...
-4
votes
0answers
43 views

How to convert byte*payload to an int? [closed]

I am programming ESP8266thing dev board using arduino. I have a value stored in byte*payload. I want to convert that value and store it into an int variable. I tried different methods but non of them ...
-1
votes
0answers
47 views

Transistor array only working on breadboard! Why?? Not a PCB problem

I have a transistor array (ULN2004AD16-U). I put THREE arrays on a breadboard. I connected an arduino to base 1 and emitter. All three transistor work just fine. I took one transistor off the ...
0
votes
1answer
34 views

Unpowered 74ls chips vs Powered Nano?

I have a power-hungry 74ls digital logic project that I want to connect a USB-connected Arduino Nano to, but I'm not sure how design the interface between them safely. The project has an external 5V ...
0
votes
0answers
23 views

Unkown fuse on the UART-to-RS485 module [closed]

Does anyone know what kind of fuses (name / item number of the manufacturer) are used on this UART-to-RS485 Module (This one) shown in the picure above?
1
vote
2answers
80 views

Converting a variable frequency to TTL HIGH and LOW levels, based on a fixed (possible non-fixed?) frequency

I have a square output from an LM324 op-amp (0 and 5 volts) which has a frequency between 1 to 500 Hz (yes, low frequencies). I would like to find a simple way to have HIGH TTL signal when it is over ...
0
votes
0answers
33 views

ATMEGA328p-AU BootLoader

I have ATMEGA328P-AU chip, to burn the bootloader I used ARDUINO Uno Board as "ARDUINO as ISP" with setup Board: Nanno. I'm getting the following error. While looking for the solution I got ...
0
votes
2answers
96 views

L293D DC motor affecting LCD display

In the circuit below, I have noticed that when the DC motor (12V) is disconnected, everything works nice. The LCD correctly displays what arduino sends to it. But ...
-2
votes
0answers
22 views

Arduino PWM & MOSFET successfully control LED but not electromagnet? [duplicate]

I've got an Arduino circuit set-up so I can control the strength of an electromagnet using a potentiometer. My potentiometer is hooked to A0, and I'm mapping its value to PWM pin 3 which then goes to ...
0
votes
2answers
63 views

Best way to power LED strip (180 LEDs)

I'm assembling this addressable RGBW LED strip setup that is 3m long and 60 LEDs/m. I have found no answer to my two questions on other sites or youtube. (This is the strip I'm using: https://www....
4
votes
1answer
117 views

Capacitors in parallel going negative

Interesting (maybe?) question here which I am struggling to answer. Hoping someone can help. I have a capacitor network; 5 caps in parallel and then two modules of that configuration connected in ...
0
votes
0answers
43 views

how to speed up sms arduino? [closed]

I am using sim800l to send SMS using Arduino to send an SMS it takes around 5 seconds because of the 1-second delay between AT commands. is there a way to speed up sms process ? or reduce this delay ...
-5
votes
0answers
36 views

above under water drone [closed]

building it for senior design project. I am using flight controller with gps https://www.robotshop.com/en/catalogsearch/result/?q=drone+Flight+Controller&order=relevance&dir=desc tracing ...
0
votes
2answers
41 views

Making a simple 1 MIDI IN + 1 arduino MIDI OUT merger (MIDI THRU + TX)

From the Midi DIN spec schematics we can see MIDI THRU is just MIDI OUT directly at the end of a MIDI IN. Is it possible to just add a midi signal from the arduino TX ("FROM UART") to the midi thru (...
0
votes
0answers
116 views

Arduino PWM successfully controls LED brightness but not electromagnet strength? [closed]

I'm trying control the strength of an electromagnet using an Arduino. I've included my circuit (sorry it's a Fritzing diagram, I'm working on the schematic and will update once it's ready) and code ...
2
votes
2answers
106 views

Building a midi project with Arduino + scrap components (optocoupler and diode)

Original title: 300V output Optocoupler in a 5V circuit I'm (new to this) trying to build a midi controller (in and out) with arduino and scrap. I guess I had several questions in one so I changed ...
2
votes
0answers
79 views

PWM to synth control voltage improvements

Just built this little circuit to control my Moog Werkstatt. The plan is to make a MIDI-to-CV converter and add more CV outputs and of course a GATE output later. But before going further, I thought I'...
1
vote
0answers
29 views

HX711 Load cell providing constant large and negative reading

I'm currently working on a project that uses the HX711 load cell amplifier while connected to a series of strain gauges in a full bridge circuit. I'm using an Arduino Nano and have the CLK of the ...
1
vote
1answer
65 views

Mosfet: gate voltage 0 but still led strip on

LED strip: DC, 4W Mosfet: IRF740 (datasheet) To Do: Use wall socket (AC) to run DC led strip and also turn it on/off with MOSFET and arduino. AC to DC is done with rectifier and transformer. So ...
0
votes
0answers
53 views

Arduino OLED Display strange output [migrated]

I am trying to use the Adafruit SSD1306 lib with my OLED display for arduino but I've encountered an strange error. I am using the default example "ssd1306_128x64_spi" but the display is odd, the ...
0
votes
3answers
62 views

doubt when Arduino connects to multiple i2c devices

I am using Arduino nano to drive multiple i2c devices, actually, they are premade modules which are available on eBay. ads1115 ADC, ds3231 RTC, 20x4 character LCD i2c module, at24c02 EEPROM module ...
0
votes
2answers
74 views

Relay Sometimes Not Switching

I have a question about relays used by an arduino. I know how to wire them and they work fine for the most of the time. But sometimes the relays doesn't correctly switch on or off. I can clearly see ...
0
votes
3answers
56 views

Is the positive supply of Arduino USB port connected to 5V pin? [closed]

You can power the Arduino Uno/Nano using the following: Barrel Jack (for UNO only), it is connected to the input to voltage regulator. VIN pin, it is also connected to input of voltage regulator. 5V ...
1
vote
1answer
59 views

74hc595 sinking, not sourcing

I'm trying to get a sn74hc595n working with an arduino Due, eventually I will be hooking up each output to an NPN to drive Nixie tubes (I am switching my design from a due to using a esp8266 so I need ...
0
votes
0answers
20 views

EMG signal from MyoWare board - sudden increase in output voltage

I am using the MyoWare muscle sensor from Advancer Technologies (this one) to obtain EMG signals from my forearm. I want to use it in a project where I will be checking if the muscle is flexed or not. ...
1
vote
1answer
51 views

Driving a motor backwards and forwards using mosfet and Arduino pin safety

So I want to drive a motor from a handheld drill/screwdriver. And I have managed to get it going using the first schematics, and using pwm to control the speed. The Zener diode is there to protect ...
12
votes
3answers
2k views

Is it safe to abruptly remove Arduino power? [closed]

If I have an Arduino, can I abruptly turn the power on and off without corrupting it? If I am designing a product that has an on/off switch, do I need to incorporate a delay before turning off the ...
2
votes
1answer
62 views

How to measure 0.02V to 0.18V audio signal with arduino?

I have a Sony STR-DE845 home theater amplifier with 8 Ohm speakers. I want to measure the voltage sent to the speakers to infer their volume using an Arduino. The AC voltage measured across a speaker ...
0
votes
0answers
34 views

Reading Digital and Analog Signal from Different Sources with Arduino

I am using an Arduino to read signals from 2 different devices. (This is an automotive project so all 3 are powered by the 12v battery of the car). The signal from one of the devices is a digital ...
0
votes
1answer
68 views

Powering LED strip from Arduino

I want to power a 5V white LED strip (50cm) from an Arduino (Leonardo, connected through long USB cable to my PC permanently). The idea is to have the LEDs dimmable through the Arduino pwm signal. I ...
0
votes
1answer
26 views

Is it possible to change gain on Adafruit PN532

Is it possible to change the gain on an Adafruit PN532 board? I need to LIMIT the range in order for it to NOT interfere with another PN532 installed close by. The board is to be used with an ...
0
votes
2answers
54 views

Measuring Power across a dummy load - use voltage or current?

I have a high power 8Ω resistor dummy load (approximating a speaker) which is being driven from the output of an audio amplifier. I want to measure the power consumption and display the results on an ...
0
votes
0answers
62 views

Converting 0-5V PWM to 0-10V PWM using Arduino and Mosfet not working

I am trying to convert 0-5V PWM coming from an Arduino to 0-10V PWM to run a motor which has PWM line that operate for 0-10V. But as soon as I connect the PWM line to mosfet it either shows only ...
0
votes
1answer
44 views

Linear actuator. Monitor end switch with arduino

For a hobby project I am developing a solar tracker. For this I obtained a linear actuator. It contains a DC motor, 2 Hall sensors and an end switch. I am using an Arduino Uno and a Polulu motor ...
0
votes
1answer
57 views

Power source project

I’m currently a computer engineering student from lorma colleges and we’re currently doing our design project. Our project is called an advance helmet. A helmet that is capable on creating a ...
-1
votes
0answers
34 views

AC/DC Power Supply for Micro Nano reading Flow Sensor Via ADC

I'm using a NANO board with a ATMEGA328p to translate a linear voltage output from a flow sensor. Its a very simple implementation that reads the ADC pin and creates a calculated pulse signal on ...