C code for W8DIZ's http://www.kitsandparts.com/freqctr2.php frequency counter board.
- Blink led on PD4.
- Standard in and out via UART (RX/PD0 - TX/PD1).
- Count pulses on PD5.
- Free Software toolchain for the Atmel AVR microcontrollers http://www.nongnu.org/avr-libc/.
- A AVR programmer like the USBtinyISP http://www.ladyada.net/make/usbtinyisp/.
- Original asm implementation in ref/ http://www.kitsandparts.com/freqctr2.php
- ATtiny2313 reference http://www.atmel.com/images/doc2543.pdf