See the top level README file for more information on documentation
and how to run these programs.
Derived from bootloader05, 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 xmodem
capabilities to the uart on the raspberry pi. (see the top level
README for more information).
The difference between bootloader05 and bootloader06 is that I made
it more lean and mean either it works perfect or it bails out, I dont
know or think the NAK stuff was working anyway. The whole xmodem
receiver is in a loop so you should be able to try again without
power cycling the board.
A new feature is that it does not automatically run your program it
waits for you to send a 'g' character (press the g button while in
the dumb terminal program). I use minicom and there is a delay between
when the external xmodem program finishes sending and when minicom
gets control again and data can be lost, data as in stuff the
downloaded program is printing out. So ideally this helps solve that.
You take the .bin file of your test program, assumed to be built based
on address 0x8000 and less than 0x200000-0x8000 bytes in size.
With uart connected to a terminal
1) power off raspberry pi
2) power on raspberry pi
3) use xmodem to transfer binary file
Repeat for each new program to test
This bootloader sits at 0x200000 so that you have 0x200000 bytes to
develop with. And that way if you like your program you can just
copy a .bin version to kernel.img on the sd card and use it. It
is easy to change this starting address, see the source for more.
bootloader01 uses .hex files, bootloader02 through bootloader06 use .bin
files, .hex files wont work. Consider bootloader01 and 02 to be
obsolete.
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).
3451556310