We use part of the excellent material from "CSE P567, Design and Implementation of Digital Systems (Winter 2010)"
by Carl Ebeling, Computer Science and Engineering Program, University of Washington

• Lecture 6: Introduction to the ATmega328 and Arduino
• Lecture 7: ATmega328 Timers and Interrupts

From the introduction to ATmege328 (“Lecture 6”) we just need:

• AVR register file: some discussions
• AVR memory
• Interrupts
• I/O ports, pin circuity

We don't need:

• Addressing modes
• Instructions

Let us work on Arduino Timer Interrupts based on material from instructables
http://www.instructables.com/id/Arduino-Timer-Interrupts/?ALLSTEPS

Modify the code from the instructable above to generate a frequency of f = 3 kHz.

• https://oscarliang.com/arduino-timer-and-interrupt-tutorial/
• http://ucexperiment.wordpress.com/2012/03/16/examination-of-the-arduino-millis-function/
• https://arduinodiy.wordpress.com/2012/02/28/timer-interrupts/
• AVR130: Setup and Use the AVR® Timers (pdf)
• https://sites.google.com/site/qeewiki/books/avr-guide/timers-on-the-atmega328