Be sure to use the Arduino Stack Exchange for questions that are more Arduino and less electronics.
0
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0answers
13 views
Powering and controlling multiple 12V LED strips with Arduino LilyPad USB
I'm trying to use an Arduino Lilypad USB to control several separate 12V white LED strips. I am however struggling to work out how to power them.
The LilyPad only operates at 3.7V and I thought a ...
1
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1answer
46 views
How to fix Hitachi HD44780 16x2 LCD garbled display in 4 bit mode?
It often happens that a HD44780 16x2 LCD shows garbled characters during usage. Most help on the web advises for using snubbing techniques to prevent voltage noise such as induction spike. I've done ...
0
votes
1answer
15 views
Burning arduino bootloader with avrdude and AVR dragon on ATmega32U4 failing
I am attempting to burn a bootloader on a ATmega32U4 aka. Arduino Micro which is not succeeding. I am using a AVR Dragon with ISP interface.
...
1
vote
1answer
47 views
Connect lots sensors (more than 10, mostly accelerometers) to Raspberry Pi by using slaved Arduino solution
I am a programmer but quite new to electronics.
I am trying to connect more than 16 sensors into a RaspberryPi for analysis, because I'm mainly focusing on computing science's machine learning ...
0
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0answers
65 views
Why do I need I large resistor to the GATE of my MOSFET?
I tried to control the brightness of a LED using a Linear Hall Effect Sensor fed to an Arduino, and PWM output to the gate of a MOSFET connected to a 12V battery.
The LED was flickering a lot, and ...
0
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0answers
19 views
XY-MK-5V suddenly stops working
I have a situation that just baffles me here...
I bought these cheap XY-MK-5V RF receivers with FS1000A transmitters. I fitted the receiver to an Arduino UNO connected to an 8-channel relay board, ...
1
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0answers
34 views
Two Arduinos Send data via Analog Pin? [migrated]
What I want to do is allow Arduino A to send some constant value to Arduino B.
I sense something inherently wrong with my approach, but I cant figure out what it is.
So in the diagram below you will ...
1
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2answers
47 views
Show different colors using RGB LED strip and Arduino
I am a beginner, I am following this post to program RGB LEDs (smd 5050).
I want few specific LEDs to glow in specific color while other LEDs are glowing in other color. Need help in doing this.
I ...
0
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0answers
48 views
One FTDI on Three Atmega [migrated]
I'm doing a schematic for an arduino project-based and I can not proceed. I'm facing a problem which I have no idea how can I solve it so that's the reason I'm writing back to you.
The thing is: I ...
-1
votes
1answer
38 views
Reading audio from the same computer where Arduino gets power supply
I have an Arduino, and I want to read from a 3.5 mm jack cable.
I powered Arduino with an USB plug to the computer. I created a voltage divider, joined the computer's output jack's one of the pin, ...
0
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3answers
41 views
Contact temperature sensor
I need a contact temperature sensor to get the temperature of a container.
Anything like LM35 which I found from google search gives me ambient temperatures. Can anyone suggest an easy to use contact ...
0
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2answers
29 views
Interfacing Arduino and Siemen's PLC S71200
I am doing a basic project relating to home automation in which i want to glow an LED/Bulb using a PLC wirelessly.
A BLE module DBM01-S is used which takes signals from an Android phone and transfers ...
2
votes
2answers
134 views
How to switch between 2 power supplies?
I have a sensor that needs in order to function 30 seconds 2V, 30 seconds 5V (on both max 300mA). I have done the power supplies, I can do the programming for the delay but I'm not sure exactly how to ...
0
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0answers
4 views
Servo Buzz / millis() [migrated]
I am having a problem with Servo Buzz that I have ascertained is from the millis() function using too much time for Arduino to generate a steady pulse for the ...
1
vote
2answers
62 views
Analog circuit to check if an audio signal is present?
On the project I am working on, I have 3 line-level audio signals, and I need to determine on an arduino if a non-silent signal exists on each line and act appropriately (in my case, "unplugging" a ...
0
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0answers
4 views
Which Arduino to choose Nano, micro or micro pro? [migrated]
I have the RC522 RFID read/write module and would like to use it with arduino? I'm puzzled at the moment which one to choose in order not to deal with voltage supply for RC522, because RFID module ...
-2
votes
2answers
39 views
Solenoid Driver Circuit
I want to drive a solenoid (12V load and 20A rating) using a MOSFET and an Arduino. What kind of switching circuit should I use?
1
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3answers
63 views
Providing a linear adjustable DC voltage from PWM ( 1.5V to 3.3V)
first of, im not an electrical engineer, so a simple task has me baffled for the last week or so.
I am working on project where I am requred to feed a blackbox device with a stable adjustable ...
3
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3answers
237 views
BC547/BC548 with 5V at base can't control 12V at collector-emitter?
For an Arduino project I needed both 5V and 12V voltages. Specifically, for an IC I needed 5V and I needed to be able to switch it on and off using an Arduino PIN. Since the current drawn by the IC ...
0
votes
1answer
31 views
Failure on connecting laptop to HC-05 bluetooth module [on hold]
I've been able to pair the HC-05 bluetooth module with my laptop, but every time I open Arduino IDE to try to send characters via serial monitor to the bluetooth COM port, the LED of the module starts ...
0
votes
1answer
59 views
interfacing barcode scanner with arduino using RS232
I want to connect a barcode scanner with Arduino. I used MAX232 to convert the levels. I have taken only 3 pins.. 2(RX) , 3(TX), 5(GND) from the DB9 cable and given them to pins of MAX232 as shown in ...
1
vote
2answers
58 views
LMP91000 I2C Write Problem
I've posted this question to TI E2E forum here. I'm cross-posting it here in hopes of casting a broader net.
I'm writing an Arduino library for the LMP91000 (github), and I'm apparently having some ...
1
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2answers
47 views
How to programatically simulate a click on a capacitance-sensitive button?
I am tearing apart a SONY HT-XT1, which has capacitive buttons to put it in a different case for a project:
I've taken it apart already and am now met with a motherboard with 3 pads on it. Touch ...
0
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2answers
66 views
Possible solutions instead of 12 relays
First of all i am new to electronics, but have some basic idea.
I want to create a USB switcher with arduino, which will control "where" the usb device is plugged in, instead of unplugging and ...
-1
votes
2answers
77 views
DIY current sensor to arduino not working [on hold]
I'm trying to build an energy monitoring device following this guide
http://openenergymonitor.org/emon/buildingblocks/how-to-build-an-arduino-energy-monitor-measuring-current-only
i hooked up the ...
0
votes
1answer
51 views
Power Supply For CNC Setup
I can't quite wrap my head around the power requirements for a CNC setup i'm building.
I'm using 3 x Easydriver 4.4 for driving the Sparkfun Stepper Motors. I previously used a 22 V 800ma Power ...
1
vote
1answer
57 views
Does both ground pins on ATMEGA are internally connected? [duplicate]
I think the title is self-explanatory but should I make the connection on PCB or they are already connected? If so, should I still connect them externally? Why?
I'm working on ATMEGA328p-pu if it ...
0
votes
1answer
26 views
Proximity detection with rfid
I am wondering if anybody has ideas for developing an (Arduino?) system that would use RFID to log occurrences when two people are in close proximity to each other (e.g., <= 1 meter). Ideally, I ...
0
votes
1answer
30 views
how to safely increase the distance between ws2811 chips
I'm designing a pick to light system based on ws2811 chips + leds and an mcu like arduino uno or mega.
The average distance between the independent light modules will be about 2m which is in the 10m ...
-2
votes
2answers
75 views
Need circuit to Switch 240v a.c. mains with 3v or 5v
I have the IRFP460 power transistor
which if I understand correctly can switch 20A/500V on 20v input.
I am wondering what a circuit design would look like that would allow me to either
(a) switch ...
0
votes
2answers
42 views
Using transistors to minimize the number of Arduino pins used for this stepper motor driver
Alright, I know very little about what I am currently asking about, but here is the gist of it:
I want to build a cnc machine out of some old floppy drives. I purchased a couple L293D dual H-bridge ...
0
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2answers
55 views
How to calculate power requirements of LED matrix, per row or per LED?
I have built an LED matrix (9x9) and want to run it with Arduino. I am using technique of scanning, lighting up 1 LED at 1 time.
The more I am reading about power requirements of a matrix the more I ...
0
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0answers
65 views
How do I write a debugger for Arduino? [migrated]
I want to write my own debugger.
I've found Visual Micro plugin for Visual Studio provides Arduino Debug.
So, does anyone have ideas how it works?
I just desire make the same plugin in Eclipse IDE.
...
0
votes
0answers
4 views
Set Arduino digitalRead reference voltage [migrated]
I wanted to know if the reference voltage for the digitalRead function could be set to a particular voltage, either with an external reference or internally.
In the Arduino reference under the ...
1
vote
2answers
66 views
Wire up multiple slave Arduino devices to a master Arduino device
I want to use serial communication between a master and multiple slaves.
I've already connected the RX of the master to the TX pins of both slaves, and vice versa (thus connected the TX pin of the ...
0
votes
1answer
40 views
Import alternative stepper motor in my fritzing sketch
I have a question, which is on the usage of Fritzing. I'm trying to sketch up a robot I have made. I want make a proper sketch, which I can send to a manufacture.
I found a stepper motor used in this ...
0
votes
1answer
40 views
bipolar linear hall effect sensor choice
I'm doing a project where I use Hall effect sensor as a proximity meter.
Using to (electro)magnets opposing each other to know a certain data when their in rest or in active state?
The states ...
0
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0answers
50 views
How much current can be safely drawn from arduino nano 3v3 pin? [duplicate]
Simple question: how much current can be drawn?
Background: I am adding a ESP8266 Wifi "module" to my setup. It says that normal operations requires 70mA, peaks at 240mA and power source must be able ...
0
votes
1answer
46 views
himidity sensor with more probes
Could you advice how to amend such schema in order to measure humidity on more probes? http://emesystems.com/images/smx/SMX555sc.gif
The 555 is functioning as a resistance-to-frequency converter. A ...
1
vote
2answers
93 views
Is a relay with a 20 amp rating enough to handle the current from a residential hot water heater?
In Israel the houses usually have a hot water cylinder on the roof of the building which is attached to a solar water heating unit, but which also is connected to an electric heating element which is ...
1
vote
0answers
29 views
How do you measure an output designed for a moving coil meter, using an Arduino?
I have a Yaesu FT-857 Amateur Radio transceiver which has an output for an Analogue Moving Coil meter.
The radio will output a current varying between zero and 1 milliamp (0–1mA), depending on the ...
0
votes
0answers
30 views
Arduino: two SPI bus or two DATAOUT on the SPI bus
In order to control several chained MBI5031 led controller, I need to send two synchronous signals over a serial bus (signals are the serial data signal of course and a Latch Enable signal). My idea ...
1
vote
1answer
68 views
Tubular Solenoids and Arduino
I am interested in using this Tubular Solenoid at 3 DC voltage to operate in Continuous (100%) Duty Cycle. According to the specifications the solenoid can operate at a:
Continuous (100%) Duty ...
0
votes
1answer
40 views
Matching impedance of the load after inverting
I have a very basic inverter circuit with a 2n3053. I basically need around 5V at the collector terminal when the base is at 0V. I am able to achieve this provided the load is not connected. When the ...
0
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0answers
39 views
Solar charge controller circuit for LiFePO4 (or possibly NiMH batteries)
Would someone happen to know of a circuit board for charging LiFePO4 batteries from solar panels. Or alternatively a simple circuit schematic for building one?
I would like to use 2 LiFePO4 ...
0
votes
2answers
53 views
Outputting 10V from 7 ports, low current
I'm working on a school project with a lighting unit that has seven inputs that read between 0-10VDC. I need some sort of microcontroller, relatively inexpensive, that can be programmed to output what ...
0
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0answers
28 views
Low-powered sms > garage port opener
I have my car in a shared garage, with a standard 433mhz garage-port opener.
I've been able to clone the opener, so I now have a tiny board with to cables that I can connect, and the garage opens.
My ...
2
votes
3answers
156 views
Burned a PIC12F675 - but why?
I'm experimenting with PIC programming controlled by an Arduino Uno, and I'm using the PIC12F675. I actually got the PIC to enter programming/verify mode yesterday and was able to read out the device ...
21
votes
1answer
543 views
Why does my AVR reset when I call wdt_disable() to try to turn the watchdog timer off?
I am having a problem where executing a disable watchdog sequence on an AVR ATtiny84A is actually resetting the chip even though the timer should have plenty of time left on it. This happens ...
1
vote
1answer
56 views
Control inverter using Arduino PWM output
I'd like to control a frequency inverter using an Arduino Uno board and inverter analog input, in order to control AC motor speed. To do this I need to vary inverter analog input voltage. Inverter ...
