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Motor control

 I have the following small problems:

In the beggining I had them posted in the wrong place,

 So i moved them here:

Problem one: i tried hooking up two motors.

they both had one wire soldered up to V2, and the other one to outputs (6 and 7). i now typed this code:


high 6

high 7

pause 3000

low 6

low 7

pause 1000

goto main

notning happened. any ideas? 

PS: i dont have a motor drive.


Now for the next important question, 


Fried?!...Back to square one...help?

Well I fried my PWM (predicted by ChristheCarpenter) by feeding it about 5 Amps. Alas, back to square one. Would like some definite help. 

I could build another PWM with a higher amp rating, but I noticed that as I put a load on the motor the speed was not constant. If would speed up, then bog down, then speed up. I'm not sure if this was due to a insufficient PWM, not enough Amps from the 1.5 A power supply, or lack of a true motor controller.

Question IRIN Command Picaxe

I am using the irin command right now and am running into a really simple problem...

It goes: irin [timeout,address],pin,var 

The timeout is how long you want it to wait before skipping ahead to the address and the pin and variable are pretty self-explanitory. What I want to know is, what address do I use if I want it to just go to the next line of code? I don't need it to go to a whole other place in the code, just the next line. --Any thoughts?

IR and pulsin

After some time of idleness i got to work again on my IR setup. I still have some problem understanding what happens.

This is my setup:

Transmitter: picaxe28x1, IR led (tsal6100)with cathode connected to pwm (%50 duty, 38000Hz), anode to an output pin.


pwm bla bla (set up of pwm)

pause 500

pulsout 7, 250


Receiver: picaxe28a, IR receiver and demodulator (tsop1238) properly connected.




pulsin INPUT_PIN, 0, w0

goto main


Would this work?

im thinking of making a robot that could follow one's feet, by using infrared.

the idea would be to use two or more infrared LED's and attach them to my Shoes and then two infrared sensors on the robot. it would roll a bit, then read witch sensor riceves more IR light, turn that way, roll, and repeat.

any chance it would work? Or am i just talking crazy talk?



Ideas for motor speed control

I have an idea of how to do a electronic speed control for some DC motor (H-bridges).
I built this circuit and it works pretty well.  Its a PWM generator based on this great tutorial .  I had to convert it to a NE556 instead of a NE555 but it works well with a 100K linear pot..


How do i use this... (underside of a button)



how do I solder a wire to this so that I can use a microcontorller to trigger it via outputs?

programming flaw?

here is my program that is supposed to make my tracked robot move towards light sources over a ceratin brightness. however, when it runs on the PICAXE28x1, it goes forward if it is started in the light, but as soon as the light level drops it turns left and does nothing else. Can anyone find the flaw in my programming?


LEGO Robots: Line follower, light follower and fighter

Hi all!

I've just posted in my website the source code and videos from my LEGO line follower robot, maybe could be insteresting for someone:



Continuous rotation servo broken.

I thought i'd make this post to help any beginners that also run into this problem, i wasted a good hour and a half on this, so hopefully no one else has to.

Contemporary Politics

Maybe this is a bad idea. Let's see what comes out of the woodwork...

voodoobot posted: http://www.flickr.com/photos/matthewkendig/2892037701/

I feel it's true to the bone. The banks lent money to people who were never going to be able to get it back and that was a bad business decision. I suspect they did it KNOWING full well that the government would bail them out.#

To all drumbot builders

Did any of you ever notice that a drummer (flesh/blood kind) does not hold his sticks at the very end? He holds them somewhere between halfway and one tenth of the length. I am guessing (not being a drummerboy myself) that this improves the rebounce of the stick from the drumskin. Because the bottom end of the stick balances (both weight and inertia) the business end. Try it out with a pencil on the tabletop. (nb: will destroy pencil)

Did you ever consider placing the motor higher up the drum stick?

DC Motor or Servo for rack and pinion drive

Hey guys...another question...which would you use and how?

I want to make a rack and pinion armature system for my bot. But I'm unsure of which direction I should go...Let me explain my ideal setup.

Two parallel rails that run in parallel with the rack. the Motor would be on a platform that uses bearing to run in the rails and the pinion to drive the platform back and forth. similar to a gantry.

Providing more power

Ok, so i have my Arduino, 3 x servos and an ultrasonic range finder.  Running all these at once from the 5v that the arduino provides is not supplying enough current (i think). I can run at maximum any two of these components from the 5v.

So i guess my solution is that i need to supply the servo's with their own separate power source.

If i hook up some AA batteries to the + wires of the servos connect the gnd to the gnd and the PWM wire to the arduino, will this work? How have other people dealt with this problem?

Arduino + 9.6 Volt NiMh Battery

Just a simple question, can i power the Arduino with a 9.6 volts battery?


Will the .6 volt fry the Arduino ?

Analog multiplexor (possibly i2c)

Hello! i have almost finished my analog inputs on my last project.. i have only one left and i need to attach some potentiometers to do some calibration.. I could really use some nice multiplexing. What i'd like is a chip with some analog inputs and possibly an i2c interface so that you can choose which analog pin to read and get a digital reading. Do you know if anything like this exists ?

Can you work with LED???

Can you make a 3d LED cube with an Picaxe 28x1.  Like a 3x3x3 or bigger.  It something second I would love to do.  Robot is the first thing I want to do but learning more about LED and wanted to know if it is possible to do something like this.  I can't wait till I place my order in soon to get this and share my project with everyone.

IR Distance Sensor Placement

Well folks,

I have now upgraded to a total of 4 Sharp IR distance sensors on a single robot (in addiition to a sonar sensor in the middle on a servo). I want this bot to drive entirely off the IR sensors leaving the sonar to simply find "interesting" things to drive toward.  In the past, using only 2, I have tried many different placements... I have tried:

One on each corner, shooting straight forward

From the middle shooting out to the corners

On each corner shooting to the opposite corner (crossfire)

Picaxe 28x1 the full package???

Well I know this had maybe been ask a long time ago so I was wondering where could we get the full package of the picaxe 28x1.  This include the USB cord also.  I remember seeing I think an UK site that comes with it but show sparkfun doesn't.  They actually charge you another $26.  That $64 and not including shipping.  Seem a bit high to me.  Forgot to mention I'm from the U.S.