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; subi_vs_andi.S: Compare the performance of `subi' and `andi'
;
; Does a bitwise "and" perform better than a subtraction on an
; Arduino Uno?
;
; There are two common ways of converting an ASCII digit to its numeric
; value:
;
;  - subtraction: character - '0'
;  - bitwise and: character & 0x0f

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/*
 * dual-scope.c: Dual channel Arduino/AVR oscilloscope.
 *
 * This program alternatively samples analog inputs 0 and 1, with an
 * overall sampling rate of about 9615 samp/s (one sample every 104 us),
 * i.e. 4808 samp/s per channel. The samples are output as 8-bit binary
 * through the serial port at 115200/8N1. A fixed 16-byte ASCII prologue
 * is sent at program startup, before the actual binary data, for
 * synchronization purposes. The first byte sent after the prologue is a
 * sample from channel 0.

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/*
 * stroboscope.ino: Pulse an LED at an adjustable frequency.
 *
 * This program strobes an LED at a frequency which is controlled by a
 * potentiometer. The frequency is continuously displayed on the serial
 * port.
 *
 * The potentiometer sets the frequency, on a logarithmic scale, from
 * 15.26 to 1012 Hz (assuming a 16 MHz clock). The output is generated
 * by Timer 1 in phase correct PWM mode with a /8 prescaler. This

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/*
 * sound-meter.ino: Arduino sound meter.
 *
 * This program continuously samples a sound signal on analog input 0
 * and outputs the computed sound intensity through the serial port.
 *
 * The analog-to-digital converter is set to "free running mode" and
 * takes one sample every 104 us. After subtracting a DC offset
 * (constant dc_offset below), the samples are squared and low-pass
 * filtered with a time constant of 256 sample periods (26.6 ms). They

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/*
 * homodyne.ino: Homodyne detection of a 1 kHz signal.
 *
 * This program continuously samples analog input 0 and uses an homodyne
 * detection scheme to identify a signal at 1 kHz (+/- 24 Hz @ -3dB).
 *
 * The analog-to-digital converter is set to "free running mode" and
 * takes one sample every 104 us. The samples are multiplied by two
 * generated signals at 1 kHz (the "local oscillator"), in quadrature to
 * one another. The products are then low-pass filtered with a time

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/*
 * interpreter.ino: Simple Arduino command line interpreter.
 *
 * This is intended solely as a template for building richer,
 * application-specific interpreters. Add your specific commands to the
 * exec() function, and whatever you need to setup() and loop().
 *
 * Usage:
 *   Talk to it through the serial port at 9600/8N1. Commands should be
 *   terminated by CR (\r), answers are terminated by CRLF (\r\n). This

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/*
 * robotic-car-test.ino: Basic tests for a small robotic car.
 *
 * Usage: keep the car in your hand and look at the serial monitor.
 */

#include <Servo.h>

// Pinout.
const int MOTOR_LEFT_ENABLE    =  6;

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/*
 * ebclock.ino: Edgar's binary clock.
 *
 * This is an alternate firmware for Daniel Andrade's binary clock.
 * For details and schematic, see Daniel's post at
 * http://www.danielandrade.net/2008/07/15/binary-clock-with-arduino/
 *
 * A few things are changed with respect to the original firmware:
 * - you can fine-tune the clock speed if it runs too fast or too slow
 * - you do not need the 2.2 KOhm pull-up resistors