Use this tag to ask about electronics-related issues with your Arduino. For example: driver transistors, Ohm's Law, current-limiting resistors.
1
vote
2answers
40 views
Voltage changes but digitalRead always HIGH
I developed simple push button project
I used wemos D1 mini
I connected D3 pin to pull down 1K resistor.
I used multimeter to measure D3 pin voltage.
When i push the button, D3 pin voltage changes ...
0
votes
0answers
22 views
Term for Two-Channel Analog Switch Module/Digital MUX
I'm looking for this 16-channel item:
...But just 2 channels. Basically one lead tells if the singal lead should travel down path A or path B. The advantage it has over the 16-channel is that it only ...
0
votes
1answer
50 views
Arduino Ground Current and DC power jack
I have a project where I'm providing power via the DC jack to my Arduino then accessing the DC power via the VIN pin. According to this http://forum.arduino.cc/index.php?topic=453955.0 I am ok to draw ...
-1
votes
1answer
32 views
Make Arduino return information from a website to a display [closed]
So I want my arduino to return the number of total-views of a youtube channel from the website socialblade.com to a digit-segment.
this is what I want:
I want to know who many total views the channel ...
1
vote
5answers
117 views
Is there any way I can light up a candle with an Arduino?
I want to make a candle flame light up triggered by a microcontroller. Is it possible? I only want to light it up. Not turn it down. Moreover, this is for a one-time use so the candle burning down and ...
0
votes
1answer
37 views
Would an Arduino Uno be suitable for a simple time-based locking circuit?
Background: I'm looking to start on my first real electronics project and I have an Arduino Uno I bought a while back. I've only done a few of the starter Arduino tutorials and that was a while back ...
0
votes
0answers
15 views
Sending and receiving IR codes with a FCE-1050 unit
The FCE-1050 is a (now discontinued) IR "combat unit" offered by Horizon Hobby for their Blade RC helis.
I'd like to use these as simple transceivers for a robot laser tag project, but unfortunately ...
0
votes
1answer
83 views
ATtiny85 AC Phase Control for dimming a light bulb
I'm trying to dim a light bulb via an ATtiny85, which accepts commands sent over I2C. My problem is that the bulb is barely dimming and is flickering quite a bit.
My circuit can be seen here:
The ...
0
votes
2answers
204 views
Hardware logic gates for a simple demo with LEDs
I need some logic gates for a simple demo like this one. I will use a regular breadboard and an Arduino UNO as a 5 V and GND supply.
I found these ICs from Texas Instruments SN74LSxxN (NOT, AND, OR, ...
0
votes
2answers
70 views
Hardware damage from executing tight polling loop over extended periods of time?
I want my project to be standing by at the ready for months and years at a time, so I started writing my code to throttle back from polling at delayMicroseconds to just delay. Like, after 15 minutes ...
0
votes
3answers
83 views
Where is the inaccuracy of my arduino thermistor circuit coming from?
I've setup four thermistors and a known resistor in series and connected them to the 3.3V output (as I've heard it's cleaner than the 5V) of an Arduino Uno (with the 3.3V also connected to ARef to ...
0
votes
1answer
33 views
Random analog input
I'm trying to build a midi controller that takes the input from a photoresistor and a reed switch anemometer and outputs midi signal.
I've constructed the circuit as in the diagram below but when I ...
0
votes
1answer
72 views
How do I control multiple LEDs strips with Arduino
I want to decorate my house with LEDs strips on each step of my stairs.
I will buy LEDs strips with a 12V power supply.
I want that if I put my foot on the first step, the first LEDs strip turn on, ...
3
votes
3answers
52 views
Can a motherboard be a simple circuit between arduino uno and a set of devices (ie: motors)
Reason for question:
My son is working on a project to build a robot controlled by an arduino uno. This question is more about terminology than process, but since terms are very important at this ...
3
votes
1answer
42 views
Getting the DS18B20 detected and temperature read
I'm quite new with the electronics part of Arduino, but I thought that this was the basic way to get the DS18B20 temperature device hooked up. However, I can't detect it in my program using OneWire ...
6
votes
1answer
103 views
Replacement crystal on Uno for cold temperatures
I want to run an arduino out in the cold (-40), and use the serial communication - I believe that the crystal is the weakest link (the one for the serial chip) - however I don't see any drop-in (...
1
vote
0answers
71 views
troubleshooting - Turn on a single led in a ws2811 ledstrip with an arduino Uno with FastLed
I want to to turn on a single led in a ledstrip running on ws2811 with an Arduino Uno.
The problem is that when I try to turn just one of them on, they all three light up. The strip is a 3-wire ...
-2
votes
2answers
72 views
Problem stopping a stepper motor with an endstop
Basically I have created the following code to control my stepper motor:
int pin_enable_motor_x = 38;
int pin_motor_step_x = A0;
int pin_direction_x = A1;
int endstop_x = 3;
void setup() {
pinMode(...
1
vote
0answers
77 views
How to sense toggle switch using OPTOCOUPLER
I am using an EL817 Photocoupler, here is the Datasheet. I have designed a circuit to sense the Switch using EL817 and it is connected to the GPIO pin of Arduino. How can I sense the switch? The ...
-3
votes
1answer
55 views
What is LCD bias voltage and where do I have to connect it?
I noticed that I have VB0+, VB0-, VB1+ and VB1- pins on my LCD. In the datasheet it says they are for the "LCD Bias Voltage". I have never heard about that. So what is it? Where do I have to connect ...
0
votes
2answers
59 views
Making three led's blink at different times in Arduino
I have a breadboard connected to an Arduino Uno, 220k resistors connected to an led, of course it has a common ground and a pin connected to 5v. All pins are digital.
Now, I want led 1 to turn on ...
3
votes
1answer
77 views
Design considerations for creating an Arduino 'shield' shield to limit EMI
I am building a shield that contains an AC power supply and relay for an Arduino-like board. The problem I am having is that the relay is quite noisy with respect to EMI, and I can see a few jitters ...
0
votes
1answer
26 views
connecting 3.3V to +3V
Well, I hope this question won' t be buried to the dark depths of this forum as my previous q' s:) But I suppose it won' t this time cause it's pretty short without this introduction part...
I have ...
0
votes
2answers
63 views
Supplying power to arduino by 5V and 2A adapter
Can I power my Arduino using a 5V/2A adapter by connecting it through the USB port?
More precisely, I have to run a module requiring 200mA but the aim is to make the laptop independent.
0
votes
1answer
36 views
Problems with running multiple ESC
I've written a program which allows me to use my Arduino Uno to send a PWM to an Electronic Speed Controller. 5 seconds after startup the ESC is sent a config via PWM to signal the low to high PWM ...
0
votes
1answer
70 views
Confusion about PNP transistors
I was reading through SparkFun's article on transistors when I came across something that confused me. The article showed this circuit:
With this description:
Similar to the NPN circuit, the base ...
0
votes
1answer
45 views
Do I need resistors or capacitors on this relay?
I'm using my Arduino to control a relay switch, which has an extension cord attached to it (see photo).
The relay is connected to the Arduino via pin 9, which is set to pinMode(9, OUTPUT);
Do I need ...
1
vote
1answer
41 views
Send button press over RF
I'm trying to send a button press over RF (performing a closed circuit operation on the receiving end).
I have a controller with an UP and DOWN button. Unfortunately I am limited to the cable length, ...
1
vote
0answers
47 views
Make your own Cheap + Value Packed Arduino Starter Kit? [closed]
so I have recently started messing around with little electronics circuits and was thinking I should get an Arduino, along with some other bits and pieces, so that I can create my own little Arduino ...
1
vote
2answers
101 views
Unable to create a desired periodic signal with Arduino Mega 2560 and DAC0808
I wrote the code to produce the periodic signal by using arduino and DAC0808 where i turned on and off the respectively pins of PORTA by using a logic in iterative manner and created the periodic ...
3
votes
1answer
52 views
RC Car Hack Issue
I am trying to hack a cheap RC car as to be able to control it using my Arduino. I took apart the cars remote controller and found the pins that make it go forwards, backwards, left, and right. So I ...
0
votes
2answers
103 views
Split Power supply in voltage and gnd?
I am new to electronics and arduino in general. I need to split a power supply in gnd and voltage. Basically, the power supply has one single wire (with the voltage and the gnd passing through it i ...
0
votes
0answers
152 views
Arduino Oscilloscope Graph Output
For physical Arduino debugging purposes, I decided to make a simple Arduino oscilloscope (on a Nano v3) based on Sofian Audrey's 3-channel oscilloscope code which is at the heart of this instructable. ...
1
vote
1answer
95 views
Electric interference from cnc spindle
I've got a CNC machine and I recently started using a spindle for it. At first it was running smoothly with no issues, but after the first brush pair wore off (I've replaced them later on) it started ...
1
vote
2answers
57 views
How to calculate the needed voltage and current to supply for Arduino
I have Arduino MEGA and I'm connecting to it 5 servomotors.
{ 3 TowerPro M995
Basic Information
Modulation: Digital
Torque: 4.8V: 130.5 oz-in (9.40 kg-cm)
6.0V: 152.8 oz-in (11.00 kg-cm)
Speed:...
1
vote
1answer
95 views
Is it safe to place a capacitor across vin and gnd?
I have a 3A fan hooked up to an ATX power supply in parallel with a transformer which powers my board through VIN/GND.
The ATX is gated by a relay on its DC side and seems to cause enough of a ...
0
votes
1answer
124 views
I want to run jvm on arduino.What minimum configuration do I need?
If Arduino IDE itself is built on Java can I run JVM on the Arduino? If yes how should I do it?
1
vote
1answer
51 views
How to reduce current from a AC TO DC power supply for arduino use
I have a AC to DC converter that was originally used for recharging the PSP, I stripped the 2 wires of the output and was wanting to use it for my arduino instead of using a 9V battery, it's output is ...
1
vote
4answers
90 views
Is it possible to make 4hz readings with the DS18S20 temperature sensor?
My current code that doesn't convince me:
#include <OneWire.h>
int DS18S20_Pin = 3; //DS18S20 Signal pin on digital 3
unsigned long startTime = 0;
#define MEASURE_PERIOD 250
//Temperature ...
0
votes
1answer
104 views
Is it safe to power an MQ-7 gas sensor with a 9V D.C supply?
I'm looking for a portable power source for an MQ-7 gas sensor. According to my research - it needs 5V D.C power with at least 0.3A of current. I'm not really good with electronics so I need to know ...
1
vote
2answers
186 views
Soldering headers screwed up Trinket?
Last week I purchased a couple of Trinkets from Adafruit (5v micro-USB). The first thing I did was solder the headers to one of them. I did the whole setup process w/ the Arduino IDE and didn't have ...
1
vote
1answer
110 views
How to check if all pins are connected on my board to make sure Arduino sends the correct pattern number on my tool
What to add on this code to check my pins state during run? And how can i trigger error using Visual basic when 1 of my pin is disconnected?
String input = "";
void setup(){
Serial.begin(9600); // ...
2
votes
2answers
215 views
Moving motion sensor?
Long story short, I'm trying to build some form of device that you can wear and it will detect when something moves behind you. I wanted to use PIR sensors for the motion detection, but I have no idea ...
0
votes
2answers
42 views
Attach headers to servo wires?
I have these 3 wires coming from a servo motor. They're very thin and flimsy and despise staying in a breadboard.
Is it possible to add headers to these wires to make them easier to put in a ...
1
vote
1answer
436 views
434 RF Transmitter and Receiver for distance measurement problem
As a student I'm working on a project where we use 434 MHz RF Transmitter and receiver pairs for distance measurement. I know that this technology is not a good choice for this, but we have to deal ...
0
votes
2answers
50 views
Machine installed with arduino suddenly turns on when usb is unplugged
Why is my machine suddenly turns ON when I unplugged the USB on my computer? Does it have connection on the auto reset feature of my arduino board?
String input = "";
void setup(){
Serial.begin(...
4
votes
1answer
354 views
Why can't most servos rotate more than around 180°
I was looking how a servomotor works. I realized that a standard servo can only turn up to 180°, but I didn't understand why. Is it because of the potentiometer?
0
votes
1answer
60 views
Need help figuring out the pinout of a seven segmented display
A friend of mine gave me a 2in. 4 digit seven segment display. But when I sat down and looked at it, I found it has 7 pins on one side and 5 on the other and no indicators of its pinout on it. The ...
0
votes
2answers
34 views
(HELP)How to read Physical Dimensions in datasheets
Sir/ Ma'am,
.
How to read the dimension labels of this IC?
0
votes
4answers
939 views
How to run 5 wires hibrid stepper motor with arduino uno?
I have a question. How to run stepper motor (Nema 17) that has 5 wires with arduino and stepper driver.
Here is the driver, stepper and Arduino when stepper has 4 wires.
http://jdreyer.com/projects/...
