Alternative OSes

Sometimes you want complete control over the Bifferboard hardware, you don't want Linux or any other operating system getting in the way. This can be achieved by changing the boot setup option in the configuration. This can only be done from the serial console:

BIFFBOOT v2.0 32-bit Loader by bifferos (c) 2009

Redistribution prohibited, all rights reserved.

Press <ESC>

'?/h/H' for help.

BIFFBOOT> c

Serial console: enabled

Network console: enabled

Boot source: MMC/SD

Load address: 0x00400000

Boot setup: Linux 2.6 parameter block

Cmndline: console=uart,io,0x3f8 init=/etc/preinit root=/dev/sdb1 rootwait

BIFFBOOT> t

Serial console: enabled

Network console: enabled

Boot source: MMC/SD

Load address: 0x00400000

Boot setup: Simple binary (entry point == load address)

Cmndline: console=uart,io,0x3f8 init=/etc/preinit root=/dev/sdb1 rootwait

BIFFBOOT>

In config, press 't' to toggle this mode on/off. Press 'w' to write the new configuration to flash. From this point on, when you upload an image, it will be loaded to the load address and executed, with no fancy Linux setup happening. The first thing that probably needs to happen is for the stack pointer to be set, then you can run whatever you want - you are already in protected mode, the board has been initialised and all peripherals are available.

I will be adding some basic projects here as time permits.