Arduino Builder Arduino Builder is a fully standalone utility for viewing, compiling and uploading Arduino sketch file and compiled ELF or HEX file (usually bootloader) to Arduino board with Arduino ...

Anyone who enjoys building electronic projects using the Arduino prototyping and would like to program their own Atmega328-PU chips. May be interested in a new Arduino prototyping kit and ...

Perhaps the most ubiquitous example is the Arduino bootloader which allows you to load code without an AVR programmer. The bootloader resides in a special part of memory, which is protected.

Starting with the Caterina bootloader, modifications were made to enable the device to be locked and unlocked for programming. This can be done in a variety of ways, depending on how things are setup.

At about $30, the Arduino isn't an expensive device, but if you want to make your own, simpler version, electronics blog Hardware Startup shows off how to build an Arduino clone for less than $5.