first commit

libraries/A4990MotorShield/README.md

@@ -0,0 +1,110 @@
+# Arduino library for the Pololu A4990 Dual Motor Driver Shield
+
+Version: 2.0.0 <br>
+Release date: 2016-08-18 <br>
+[![Build Status](https://travis-ci.org/pololu/a4990-motor-shield.svg?branch=master)](https://travis-ci.org/pololu/a4990-motor-shield) <br>
+[www.pololu.com](https://www.pololu.com/)
+
+## Summary
+
+This is a library for an
+[Arduino-compatible controller](https://www.pololu.com/arduino) that
+interfaces with the
+[Pololu A4990 Dual Motor Driver Shield for Arduino](https://www.pololu.com/catalog/product/2512).
+It makes it simple to drive two brushed, DC motors.
+
+## Getting started
+
+### Hardware
+
+The
+[Pololu A4990 Dual Motor Driver Shield for Arduino](https://www.pololu.com/catalog/product/2512)
+can be purchased on Pololu's website. Before continuing, careful
+reading of the product page is recommended.
+
+#### Compatible Arduino boards
+
+This shield should work with all Arduino boards and clones that behave
+like a standard Arduino board. We have specifically tested this shield
+(using this Arduino library) with:
+
+* Arduino Uno R3
+* Arduino Leonardo
+* Arduino Mega 2560
+* Arduino Due
+* Arduino Duemilanove (ATmega328P)
+
+This library configures Timer 1 on the Uno R3, Leonardo, and
+Duemilanove to generate a 20 kHz PWM frequency for the motors. The
+library uses analogWrite on any board that does not use an ATmega168,
+ATmega328P or ATmega32U4. On the Mega 2560 and Due, analogWrite
+generates 489 Hz and 1 kHz PWM frequencies, respectively, with the
+default timer configuration.
+
+
+### Software
+
+If you are using version 1.6.2 or later of the
+[Arduino software (IDE)](https://www.arduino.cc/en/Main/Software), you can use
+the Library Manager to install this library:
+
+1. In the Arduino IDE, open the "Sketch" menu, select "Include Library", then
+   "Manage Libraries...".
+2. Search for "A4990MotorShield".
+3. Click the A4990MotorShield entry in the list.
+4. Click "Install".
+
+If this does not work, you can manually install the library:
+
+1. Download the
+   [latest release archive from GitHub](https://github.com/pololu/a4990-motor-shield/releases)
+   and decompress it.
+2. Rename the folder "lps-arduino-xxxx" to "A4990MotorShield".
+3. Drag the "A4990MotorShield" folder into the "libraries" directory inside your
+   Arduino sketchbook directory. You can view your sketchbook location by
+   opening the "File" menu and selecting "Preferences" in the Arduino IDE. If
+   there is not already a "libraries" folder in that location, you should make
+   the folder yourself.
+4. After installing the library, restart the Arduino IDE.
+
+## Example program
+
+An example sketch is available that shows how to use the library.  You
+can access it from the Arduino IDE by opening the "File" menu,
+selecting "Examples", and then selecting "A4990MotorShield".  If
+you cannot find these examples, the library was probably installed
+incorrectly and you should retry the installation instructions above.
+
+### Demo
+
+The demo ramps motor 1 from stopped to full speed forward, ramps down
+to full speed reverse, and back to stopped. Then, it does the same
+with the other motor.
+
+## Documentatation
+
+- `void setM1Speed(int speed)` <br> Set speed and direction for
+  motor 1. Speed should be between -400 and 400. The motors brake at 0
+  speed. Positive speeds correspond to motor current flowing from M1A
+  to M1B. Negative speeds correspond to motor current flowing from M1B
+  to M1A.
+- `void setM2Speed(int speed)` <br> Set speed and direction for
+  motor 2. Speed should be between -400 and 400. The motors brake at 0
+  speed. Positive speeds correspond to motor current flowing from M2A
+  to M2B. Negative speeds correspond to motor current flowing from M2B
+  to M2A.
+- `void setSpeeds(int m1Speed, int m2Speed)` <br> Set speed and
+  direction for motor 1 and 2.
+- `void flipM1(bool flip)` <br> Flip the direction meaning of the
+  speed passed to the setSpeeds function for motor 1.  The default
+  direction corresponds to flipM1(false) having been called.
+- `void flipM2(bool flip)` <br> Flip the direction meaning of the
+  speed passed to the setSpeeds function for motor 2.  The default
+  direction corresponds to flipM2(false) having been called.
+- `bool getFault()` <br> Returns true if pin 6 is being driven low by
+  one of the error flag outputs.
+
+## Version history
+
+* 2.0.0 (2016-08-18): Updated library to work with the Arduino Library Manager.
+* 1.0.0 (2014-08-15): Original release.