bootloader

I was trying to understand how Android interacts with hardware to send SMS messages over the RF chip, but I was facing difficulties in understanding the relationship between kernel, software, hardware, operating system, Android Java files, boot image, system image, as well as how to create them...

Hi there, I spent a while searching the forum but didn't find hints targeting my question: I want the Mega to boot from a hex-file from the SD card. While it is obviously possible to transfer a compiled sketch to the Arduino Mega via an Ethernet connection, what is necessary to reset the board...