Makelangelo+AMS2 speed boost

Did you build a Makelangelo 2.5 with an Adatruit Motor Shield v2? Here’s a trick I found today that’ll give you a 4x speed boost.

Open your firmware_ams.ino file and add the following lines anywhere inside setup():

[code]#if MOTHERBOARD == 2
// Change the i2c clock from 100KHz to 400KHz
// https://learn.adafruit.com/adafruit-motor-shield-v2-for-arduino/faq
TWBR = ((F_CPU /400000l) – 16) / 2;
#endif[/code]

Then upload the code to your Makelangelo and run.

The Arduino talks to the AMS2 shield with a protocol called i2c. What this does is quadruple the i2c speed. The i2c speed is the bottleneck that caps the top speed on the machine.

Your Makelangelo 2.5 can now run as fast as the Makelangelo 3. Someone will have to add acceleration to keep things moving smoothly at the start and end of lines. Good problem to have!

This fix will be in the dev version and make it out to the release edition soon-ish.