Video 6, Arduino School – Fixed Point Arithmetic

This video explains the use of fixed point arithmetic as an alternative to floating point on the Arduino.

Eliminating floating point from your program can speed it up and use much less flash memory – leaving more room for your program.


R1 Embedded Source Code 1.0

Here is the source code for R1 version 1.0. It’s just the embedded half – I still have to license the host code.

It’s Open Source under the GNU General Public License. This means that you can do anything you like with the code but, if you distribute copies (even compiled copies burned on to chips) you must also distribute the source code with it. Including your modifications.

If you want it with a different license, contact me.

The code compiles and runs fine with Cygwin make. It would take some skill to get it to compile under a different environment such as the Arduino IDE.

I’ll try to explain what’s going on in the code in later postings. For now, Click Here to download.

– Ralph

Brain Teaser

As shown in this bottom view, R1 has two drive wheels (the yellow wheels) and a caster wheel (the silver looking thing). The only way the software can drive the robot around is by setting the speed and direction (forward or reverse) of each wheel. The left speed and direction can be different from the right.

Controlling only the speed and direction of each wheel, how would you make R1:

  • Go forward in a straight line?
  • Turn toward the left?
  • Spin clockwise in place without really going anywhere?

My answers will be disclosed in a new video coming soon to ralphsrobots!