How to program Arduino by using USBasp without bootloader

By using USBasp, we are able to download the program directly to the Arduino Duemilanove board or others AVR microcontroller without pre-program bootloader. AVR USBasp is a USB in-circuit programmer and it can use to program most of the ATmel AVR controllers. It simply consist of an ATMega8 and a couple of passive components such as resistors, capacitors, LEDs and ect. The programmer uses a firmware-only USB driver and there is no special USB controller is needed. In this tutorial, we will show how to modified the Arduino Software so that you can use it to program AVR microcontrollers without pre-program bootloader.