Let's Make Robots!

arduino infrared help

Anyone out there successfully used the IR libraries with arduino? Calculon is trying to use it with some bots, but not in the way the libraries are written. Calculon is trying to get one duino to talk to another using a byte, the way that a Picaxe can.

All the code and tutorials he has googled seem to be for emulating or talking to a remote control and figuring out the protocol of that remote.

use mains AC as a switch for arduino?

hey gang, does anyone know if it's possible to use mains AC as a switch for the 'duino?

A little background:

Calculon is working on a project that he hopes will take advantage of his doorbell's AC power. He wants the old-school analog doorbell switch to activate a function on his arduino instead of firing off a solenoid in the door chime. Is this possible with some sort of voltage divider? He doesn't need to measure the current, voltage, phase, or anything liek that, he just needs to sense on/off like a pushbutton. He assumes the initial doorbell voltage will be 120V.


Hello all, quick (and probably dumb) electronics question. Suppose Calculon had 3 7805 voltage regulators in parallel, like such: 

Would such an arrangment share the load evenly?

Bluetooth and Arduino

Happy Holidays LMR,

Calculon is wondering if any of you have used bluetooth with arduino successfully. And if so, what did you use?

He's aware that there's an Arduino BT board, but he's looking to use a standalone module with his Mega to talk to his android phone. Anyone have any experience with this?

Would this work for this purpose?


Guten tag LMR,

Calculon is going to build this ciruit, but he wonders if his fellow LMR can comment on it before he starts. He's tested each component, but hasn't put them all together yet. Calculon's multimeter just blew a fuse, so he can't really measure the output at the moment. He has a wicked cool motor controller and he doesn't want to accidentally convert it to smoke. Here's the circuit:


powering a picaxe

Hello all LMR,

Calculon continues to work on his XMOS challenge, but has once again come across a snag.

The SNAG: He is trying to power his picaxe with a 5v out from a motor controller. It doesn't work.

Calculon's Arduino Serial madness, part 2

Hello LMR,

Calculon has been tinkering with his Arduino for a few months now and he likes it. He is at the point where he is trying to get his 'duino to communicate with another device. His question is: HOW?!?!?

More specifically:

1. Does he use the Serial.print command? Serial.write?

2. How does he send more than one byte at a tyme?

3. Here's an example of the required byte sequence:

     in hex: 0x8D, 0x7F
     in decimal: 141, 127

Does he just send one byte, and then another? 

Best way to monitor battery level?

With a picaxe or arduino. Best answer gets a cookie. OK, Go!

arduino functions

Calculon is discovering the wonders of arduino programming, and he is confused with the function (subroutine) action. He defines and declares a function, but nothing happens. Behold the simplified code:

void loop(){

   goMotor;   //call the goMotor function


void goMotor(){    //activate dc motor via h-bridge