ATMEL STK500v1 compatible boot loader for Arduino ATMEGA328.

Compile firmware

git clone https://github.com/Optiboot/optiboot
cd optiboot/optiboot/bootloaders/optiboot/
./makeall.arduino.sh

List firmware

ls *.hex
optiboot_atmega1280.hex          optiboot_diecimila.hex
optiboot_atmega1284p.hex         optiboot_lilypad.hex
optiboot_atmega168.hex           optiboot_luminet.hex
optiboot_atmega168p_16MHz.hex    optiboot_pro_16MHz.hex
optiboot_atmega168p_UART__.hex   optiboot_pro_20mhz.hex
optiboot_atmega328.hex           optiboot_pro_8MHz.hex
optiboot_atmega328_pro_8MHz.hex  optiboot_sanguino.hex
optiboot_atmega32.hex            optiboot_wildfirev2.hex
optiboot_atmega88.hex            optiboot_xplained168pb.hex
optiboot_atmega8.hex             optiboot_xplained328pb.hex
optiboot_bobuino.hex             optiboot_xplained328p.hex

optiboot_atmega328.hex

USBasp

avrdude -c usbasp -p ATMEGA328P -e -u -U lock:w:0x3F:m -U efuse:w:0xFD:m -U hfuse:w:0xDE:m -U lfuse:w:0xFF:m
avrdude -c usbasp -p ATMEGA328P -D -u -U flash:w:optiboot_atmega328.hex
avrdude -c usbasp -p ATMEGA328P -u -U lock:w:0x0F:m

Pololu USB AVR Programmer v2.1

avrdude -V -B 5 -P `pavr2cmd --prog-port` -c avrisp2 -p ATMEGA328P -e -u -U lock:w:0x3F:m -U efuse:w:0xFD:m -U hfuse:w:0xDE:m -U lfuse:w:0xFF:m
avrdude    -B 5 -P `pavr2cmd --prog-port` -c avrisp2 -p ATMEGA328P -D -u -U flash:w:optiboot_atmega328.hex
avrdude -V -B 5 -P `pavr2cmd --prog-port` -c avrisp2 -p ATMEGA328P -u -U lock:w:0x0F:m