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Top new questions this week:

Equivalent for PORTB in Arduino Mega 2560

Like I said in the subject, I would like to know the equivalent for the instruction: PORTB |= 0x01; PORTB &= ~0x01; More precisely I was using it to trigger a fast pulse conversion on my ...

arduino-mega port-mapping

asked by Francesco Pegoraro 4 votes answered by Edgar Bonet 4 votes

How to multiplex multiple displays?

I want to use 2 "displays" with 4 digits. The displays are common cathodes with cathode transistors connected to the digits, as the figure: The segments of both displays are connected together on the ...

arduino-mega multiplexer 7-segment

asked by user29787 3 votes answered by st2000 2 votes

avrdude: stk500_recv(): programmer is not responding - OSX10.11

I'm getting the following error with a genuine Arduino Uno on Mac OSX10.11 El Capitan when uploading to it (the green light is on, the orange light flashes intermittently while attempting to upload). ...

arduino-uno ftdi programmer

asked by Agent Zebra 3 votes

Multiple tones with one piezo buzzer

I have figured out how to make a piezo buzzer play two tones at once with analogWrite() and tone() but how would I make an actual song by playing both bass and treble, such as this one. Here is the ...

arduino-uno pwm piezo

asked by Amorris 2 votes answered by gilhad 1 vote

Volatile variable not updating from timer ISR

I know this is a problem that has come up many times but I can't seem to get this code fragment to update the count variable on an ATMEGA328P. I am using an Arduino Uno as a development board, with ...

arduino-uno atmega328 timers isr

asked by Matthew Curlis 1 vote answered by Nick Gammon 1 vote

How to fix compilation error for tone() using same timer as other function

I am trying to integrate tone() with the open source program for the Amped heart rate monitor. The error: Tone.cpp.o (symbol from plugin): In function `timer0_pin_port': (.text+0x0): multiple ...

arduino-uno timers

asked by rur2641 1 vote answered by Nick Gammon 1 vote

How can I make this code read a page every 10 seconds?

I got problems with the code and I have used most of today, trying to find a solution and it's starting to drive my crazy. I hope one of you guys will be able to help me out. I need the code to check ...

serial ethernet lan

asked by Kenneth Poulsen 1 vote answered by Mark Smith 1 vote

Greatest hits from previous weeks:

How do I erase the memory of the Arduino Uno?

I'm just a tinkerer learning Arduino with my son and I was surprised that when I plugged the USB cord back in to the Arduino the program was still running and I thought to myself, "it's a good thing I ...

arduino-uno safety flash

asked by Peter Turner 10 votes answered by Manishearth 13 votes

Arduino Mega timeout communication with programmer error

I have an Arduino Mega 2560 and it was working fine until about lunch time when I started getting this error: avrdude: stk500v2_ReceiveMessage(): timeout avrdude: stk500v2_getsync(): timeout ...

bootloader arduino-mega avrdude

asked by bladepanthera 9 votes answered by m3z 2 votes

Can you answer these?

Arduino pro mini (clone) @1Mhz target does not answer

Recently I have been experimenting with battery powered sensor (mySensors). I created node with 3.3V Arduino Pro Mini (ATMega328P @ 8Mhz with nordic radio chip and BME280 sensor) and successfully ...

programming arduino-pro-mini usbasp

asked by MightyPolo 1 vote

Flash String Helper object as variable

So I have a Bunch of commonly used char arrays to build commands in my library. So to preserve memory, I have them put into flash, via PROGMEM ext, typedef const char PROGMEM ProgChar; ProgChar AT[] ...

arduino-uno esp8266 flash progmem

asked by Steven Venham 1 vote

How to create a heart rate detection system that uses a chest strap?

I want to create a system that uses a chest strap from available Bluetooth-based heart rate monitoring systems. The straps seem very convenient compared to available Arduino pulse detection systems ...

sensors

asked by rur2641 1 vote