OMAP3 on BeagleBoard contains a BootRom. With this, BeagleBoard can boot without any code in permanent storage (NAND) or from peripherals. This is useful for first board bring up or if your BeagleBoard is bricked. This BootRom is able to download code via serial connection from development host PC. For this, a PC (serial download) tool is necessary to talk with BeagleBoard using the protocol OMAP3 BootRom on Beagle expects.