See the top level README file for more information on documentation and how to run these programs. This is a very simple bootloader. Instead of the sd dance (see top level README), this makes life a bit simpler and greatly reduces physical wear and tear on the sd card socket. Do the sd card dance one more time with this kernel.img. Get some sort of serial solution to connect a dumb termial program with the ability to download raw/ascii files. bootloader01 was .hex based, this one is also .hex based but a different way to parse it. bootloader02 through bootloader06 expect binary files, a binary image of the memory starting at address 0x8000. I intend to release bootloader08 at the same time and it will be .bin based but have the go feature. This bootloader07 parses intel hex formatted files. Look that up at wikipedia, it is very simple and historically widely used for bare metal embedded work. (S record is another format like intel hex but of course motorola had to have their own. Intel hex and Motorola S- record). I felt like doing another state machine and honestly had forgotten I did one before in bootloader01. This bootloader does not make any of the others obsolete, it was just a fun exercise. The thing that annoyed me the most about my bootloader is that I use minicom and minicom spawns a separate program to do the file transfers, xmodem, ascii, kermit, etc, and there is a delay and a loss of data when the spawned program exits and minicom returns. The solution is that you hit the g key when you want the program to start so you are basically back in the terminal at that point. I normally do not deliver binaries. In this case I have included all of the build files so that you can at least get started without having to build the bootloader. Backup whatever kernel.img file you are using and replace with the kernel.img file in this repo (on your sd card) to use this program. If on a Raspberry Pi 2 then use kernel7.img instead of kernel.img. blinker.hex is for older RPi boards the A and B whose activity led is tied to GPIO16. The A+, B+, and RPi2 use GPIO47, also on these latter boards the power led is on GPIO35. Last I checked they wouldnt provide a schematic for these latter boards (so much for being "open") so we have to just go on faith...