Simple AVR Frequency meter 40 MHz
This Project shows you how to build a small, cheap and simple frequency meter, without any fancy, out of reach components. The simple proposed design can measure frequencies up to 40 Mhz with errors below 1%! This degree of precision will be more than enough to debug most of your analog and digital circuits, and will give you the ability to analyze many aspects that you were unable to see before. The design is built on a ATMEGA16 micro controller. There are no crystal oscillators, as we are using the internal RC oscillator, calibrated to 8 MHz. To programming the AVR microcontroller it used C code which is compiled with winAVR.
Download the source cdoe (C file) | source