Let's Make Robots!

(Solved!) Low current from Arduino Output (Arduino Start Here robot)


EDIT: LED problem solved thanks to RobotFreak. I forgot to set the pins to output mode using the pinMode command. As RobotFreak points out, the Arduino sets all pins as inputs by default. I added a For loop to set all the pins to outputs, and everything worked great.

void setup() {
  pinMode(13, OUTPUT);  
  for (int pinindex = 0; pinindex < 14; pinindex++) {
     pinMode(pinindex, OUTPUT);  // set pins 0 to 13 as outputs

It's 4AM: Arduino SHR Coded but not built

I've been planning an Arduino version of the Start Here robot. Today most of my parts arrived from SparkFun. This bot will be based on Ro-Bot-X's Arduino Shield for building robots.

Greater than 360 Servo (not continuous)


There was a question in the Shout Box earlier from noise0. He wants to turn a turret with srf08 sensor and be able to rotate at least 360 degrees. But it does not have to be continuous. He can go from 0 to 360 and then reverse direction back to 360.

There were a lot of ideas including a super modified servo (http://www.01mech.com/supermodified), stepper motor, or motor encoders.

LaunchPadding - A Robot Pad for the LaunchPad

I am going to use this forum post to collect my thought on building a robot shield for the TI LaunchPad. Comment and suggestions are much appreciated.


Rather than use the Arduino term 'shield', I'm going to try to coin a term and call adding a board to the LaunchPad "padding". So this is my Robot Pad for the LaunchPad. The Robot Pad will provide flexible options for powering motors, servos, sensors, etc.

Planned Features


LaunchPad Breadboard Shield link

I found some interesting MSP430 projects on the simpleavr.com website, including this LaunchPad Shield. It is just a breadboard for prototyping, but I thought it was pretty neatly done. I may create a variation.

There are a couple of other projects posted as well, with the promise of more to come.

Also, this person works exclusively in Linux, so if you are a Linux user looking for help on the MSP430, you may want to check out this site.

Power for the TI LaunchPad


Power for the TI LaunchPad can be supplied via the USB connector. The USB power is +5V. Apparently the onboard FTDI chip converts the 5V to 3.3V for the MSP430 microprocessor. The micro power is 1.8 to 3.6V.

I'm planning a home-made shield for the LaunchPad, and I will need more than just the 3.3V for motors, servos, sensors, etc. The 3.3V from the FTDI is very current limited anyway.

TI LaunchPad External Crystal

Today I decided to solder the external 32 MHz kHz crystal supplied with the LaunchPad. I quickly discovered that the LaunchPad board itself has both SMD and through hole solder pads, but the supplied crystal is surface mount. I'd never soldered surface mount before, and there are no instructions anywhere I can find on soldering this crystal to the board.

100% up to date on everything

Frits made a big deal in the shout box today after I posted that I had caught up with ALL the forum posts. He suggested I make a blog about it, so here you go, Frits!

There was a little "easter egg" suprise message that comes up when you have no unread posts.

TI LaunchPad

I picked up in this thread that TI has entered the hobbyist microprocesser market populated by Arduino, Picaxe, Basic Stamp, etc.

At $4.30 US including shipping, they have definitely priced this development kit to sell. It looks like an interesting system, and I couldn't beat the price, so I ordered one. I understand demand is quite high, so I don't know when it will arrive.

I figured that this new entry to the market deserved its own forum topic.