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Servo mounting for "up-down" movement

hello, i was just wondering: which is the best way to attach a servo to a chassis so that it can move an attached camera up and down (no left-right) ?


YAAPQ = Yet Another Arduino Programming Question

 After struggling to wrap my head around programming the Arduino in C I completely understand why Frits recommends starting out with the PICAXE...However, I am too stubborn to give up and switch to the PICAXE so I have another question.

Led controller

Hi this is an led controller  there can only be one led on at a time it was on crocodileclips i don't know what its called but if anyone does that would be helpful. when A is high 0 is on if B is high 1 is on if A and B are high 2 is on and when A and C are high 3 is on or somthing like that.


a few questions regarding picaxe 28x, ,voltage regulators and SRF08


well im working on my first robot and i have the picaxe 28x1 board from the start here guide

i am trying to connect an SRF08 to it, i understand i should connect it with i2c,

i looked in the picaxe 28x1 manual (http://www.rev-ed.co.uk/docs/picaxe_manual1.pdf page 28)

and it says that the scl and sda are legs 14 and 15

my question is, where are these legs on the board?

is it really input 3 and input 4?


my second question is about the v1 and v2 on the board

Newbie questions

Hi im azu, im new here, and I've finally decided to jump into robotics.  I took everything apart as a kid, figuring out how everything was made and i still think short circuit and wall-e are the two best movies of all time.  Little did i know programming them was so easy.  So i decided to jump right in and make one similar to the "start here" robot.  


best sensor for object sensing?

well more like geese? ha!

 i was thinking maybe just using a sound sensor to go towards to sounds of the geese..

would that be the best way?
i dont think infared would be the best since the geese are outside and it could sometimes be bright.

sound help needed

im waiting on parts to finish my blimp bot and to make a line follower walk though. but whilst thinking about the line follower i came up with wacky racer crazy line followers. This is something im sure every one will like. what im after is code for a horn sound and a plane engine running sound and a car engine running sound plus a skiding sound. i havent  tryed to code for these sounds myself yet but it would save me alot of time if some one has already got them and i can post the walkthouhgh quicker. also im only useing a peizo not a speaker

thanks in advance


Servo Oddness

Ok, just got sensors and servos for my robot. I am using a picaxe 28x1 . Here's the thing, I know there is a bug in the picaxe a.4 firmware and it may cause servo problems. When I do  the servo command (servo 0,150 etc.) the servo does not do anything. When I plug in the battery pack (I am using two power sources) the servo buzzes a little bit thats all. I assume that this is because of the buggy firmware. When researching this bug on LMR I discovered that some people got their servo to work by using servo 7,150 when the servo was plugged into digital input 0.

motor driver idea

Hey all,

I'm trying to create a bot that uses a lot of forward/backward motor action, and I'm hoping to make a low-power, small, lightwieght motor control using switch transistors. However, my electronics experience is -5. I came up with this idea that seems simple and effective, but I'm sure there's something I don't understand about the process. So with that in mind, here's my ultra-simple H-bridge.


how to get 7493 to work

i have been trying for the last few nights tyring to get my counter to work

the wireing should be correct ,


grnd- ground

input a, to pin 9 on the arduino and it is set to a constant 150 PWM

input b - connected to Qa

Qb, Qc Qd, to LEDs

do i need to hook up the R pins?

 i know the PWM works

and there is power going to the chip

but no counting is going on, so any help would be appreciated

Arduino coding help

Hello I recently visited the arduino playground site to look how to control two servos and when i used thier code it brought up an error thing is anyone willing to post some code for me on controlling two servos please.

Computer Networking (and your experiences)

After exams I was going to throw a LAN party and the game was going to be Starcraft. I just got the computers talking and sharing files to eachother, so the next step is to add the others and install the game. The specs of the comptuers are:

Pentium II

32/64mb of ram

basic vid card, one of them has a 9800radeon vid card

all 10GB but one has a 250GB

floppy disk

CD drive

Help! Servo is only turning clockwise

My servo is only turning clockwise the same length everytime no matter what number I have in my code.

servo 0, 150 or whatever number. It goes until it hits the end.

I have 3 wires black red and white. The black is on the pin I soldered on the Picaxe 28x1. 

I have a standard servo that I bought here: http://www.hvwtech.com/products_view.asp?ProductID=878

Everything else is working. My SRF05 led is blinking when I imput the code. And my motors are working with the code.

Reversed battery protection

Hi guys, i'll start by giving you this circuit:


The circuit breaker (the PTC at the top named "CB1") and the Zener diode ("D1") have been added for overcurrent and overvoltage protection. But now my concern now is about protection from reversed batteries. What i wanted to ask you is: is it better to add the p-channel mosfet or shall i take it out?

Live video streaming for remotely operated robots, solutions?


I recently tried a small videocamera like this one, and i must say that, despite the low quality, they do a decent job, except when heavily shaked.

Now, the main problem is that they have a limited range, and that they have a radio signal on their own, separated from the main robot control. This means that you cannot make a program that behave based on the images, and that the two radio signals can have different ranges.


How could you all have forgotten Keepon!

Those two eyes actually are two cameras! and the nose is a mic. have a look at the site http://beatbots.org/

PWM for servo and motor speed

So I've looked around and see that Arduino motor shield board uses timer1  (pins 9 and 10) for hardware PWM control of motor speed. There are Arduino libraries that use timer1 for hardware PWM control of servos.

Timer1 gives you 16 bit resolution. The other timers (timer0 and timer2) have only 8 bit resolution.

Difference between #Define and INT

I have seen both used in some Arduino tutorials and I was curious as to the difference.  From what I've read #Define ledPin 13 and int LedPin = 13; do the same thing.  What dont I know?

Contents of the Electronics Surprise Box Revealed!

For any of you who have shopped around at the Electronics Goldmine (whom I highly recommend www.goldmine-elec.com) you may have been sceptical about ordering the electronics surprise box from the misc. section. Maybe you didn't know what was in it, would it be worth it, or what kinds of components and parts are in it. Well today is your lucky day because here is what came in mine! Now you can decide for yourself. (Note: not all surprise boxes contain the same typs of parts, it is purely random)

How to make port-c's into inputs

This is very simple, I have 2 picaxes talking to each other. I am already using the int command for another reason. Right now, I need to set up a handshake before one pic tries to send a serial command to the other and to be sure the 2 pics are not trying to send to I2C at the same time. I have portc 5 going to portc 5 and portc 6 going to portc 6. one 5 is an input, one 5 is an output. One 6 is an input, one 6 is an output. I have the outputs down: High portc 5 and high portc 6.


What is the command to allow a portc pin to become an input?