// this sketch turns the Arduino into a AVRISP
// using the following pins:
// 10: slave reset
// 11: MOSI
// 12: MISO
// 13: SCK

// Put an LED (with resistor) on the following pins:
// 9: Heartbeat - shows the programmer is running
// 8: Error - Lights up if something goes wrong (use red if that makes sense)
// 7: Programming - In communication with the slave
//
// October 2010 by Randall Bohn
// - Write to EEPROM > 256 bytes
// - Better use of LEDs:
// -- Flash LED_PMODE on each flash commit
// -- Flash LED_PMODE while writing EEPROM (both give visual feedback of writing progress)
// - Light LED_ERR whenever we hit a STK_NOSYNC. Turn it off when back in sync.
//
// October 2009 by David A. Mellis
// - Added support for the read signature command
// 
// February 2009 by Randall Bohn
// - Added support for writing to EEPROM (what took so long?)
// Windows users should consider WinAVR's avrdude instead of the
// avrdude included with Arduino software.
//
// January 2008 by Randall Bohn
// - Thanks to Amplificar for helping me with the STK500 protocol
// - The AVRISP/STK500 (mk I) protocol is used in the arduino bootloader
// - The SPI functions herein were developed for the AVR910_ARD programmer 
// - More information at http://code.google.com/p/mega-isp