Let's Make Robots!

Mixed power sources, stepper motors, arduino, and pololu stepper driver

I'm building a 3D printer and I'm a little over my head. Right now I'm trying to make sure most of my components play nice with each other with some simple code and only one motor.  Here's my set-up:

Seeeduino Mega fully Assembled

I have a seeeduino mega. More on the pinouts later. It's being powered via USB and I don't know if that's okay.

 

Molon Mystery

RTTTL, Arduino, Sound, Sounds, Music, Seeeduino
I was wondering why, despite the notice on the front page,  there weren't very many robots with sound. Then it hit me: people don't know how to make sounds with … Read more

Self-Replicating Stationary Phototrophs

How many of you guys garden?

LED "reaction time"

I'm thinking of using a bunch of LEDs for a secret project. Here's the catch: they have to be able 'flicker' too quickly for the human eye to see. 

How quickly do LEDs go from off to on? Is there any delay - do they have to 'warm up' like incandescent light bulbs? Realize a half second delay is way too much for the project I have in mind. Are there any fast-acting LEDs out there? Or is it virtually instant, only hindered by the speed of the electrons through the wire?

Picaxe 'No Hardware Found' and Breadboard

Some of you may remember way back when I had tons of problems with programming my picaxe. Well, they're back with a vengeance.

I recently got a breadboard and decided to try programming my Picaxe-08M with it. I followed this image:

Electronics questions

I'm pretty bad with electronics... I'm more about putting things together I guess. But I need a little help:

I don't understand how a power source (battery) has amps. Isn't current (amps) a function of voltage and resistance through ohm's law? Is it possible to blow something with too many amps like it is with volts?

While we're at it, what happens when you put a voltmeter behind a resistor? Where does that number come from?

Picaxe verification error.

So, before, I got the error: No hardware on com 1.

I have tried the hard reset, it starts downloading, and I get :

"Download For Picaxe on com1 failed

Error:

Verification error - 0x00 transmitted but nothing received at byte 0"

occasionally, it is "...nothing received at byte 37" 

I get this with both my 14m and 08m. What am I doing wrong?

 

picaxe programming

Does the picaxe programming circuit need to be in place while a picaxe is running? In other words, can I use a breadboard and picaxe breadboard adapter ( http://www.sparkfun.com/commerce/product_info.php?products_id=8331 ) to program it and then put the chip on a pcb separate from the breadboard?

5v voltage regulator

I'm using 5v regulator (this one:http://solarbotics.com/products/lm2937/) and it doesn't seem to be working correctly. I'm under the impression that this is how it should work:

picky motors?

 So I'm a complete beginner at this. I know ohm's law and generally what components do, but I've never tried to put anything together yet.