Blob, the boot loader

LART comes with its own boot loader, blob (Boot Loader OBject). Blob is copyrighted by Jan-Derk Bakker and Erik Mouw, and released with a slightly modified GNU GPL license. It's slightly modified because we don't consider the operating systems that blob boots as a derived work.

Blob can…

• initialise the hardware (CPU speed, memory, interrupts, RS232)
• boot a linux kernel and provide it with a ramdisk
• download a kernel or a ramdisk to the LART
• write a freshly downloaded kernel or ramdisk to flash memory
• determine the memory layout (and tell the kernel about the results)
• give a command line to the kernel

Blob wish list (which is also the to-do list) in no particular order:

• Parameter block support
• Ethernet support (boot from bootp+tftp)
• Memory setting calculation utility
• Z-modem download

Using blob on the LART

First connect a terminal (or a terminal emulator like miniterm or Seyon) to the LART's serial port. Use the following settings for your terminal: 9600 baud, 8 data bits, no parity, 1 stop bit, no start bits (9600 8N1, a pretty standard setting for Unix systems). If possible, use VT100 terminal emulation. Switch on the power to the LART. The LART should respond with: Consider yourself LARTed! Running from internal Flash. Starting the memory tester... Zeroing memory...0xD0000000 Zeroing done. Testing for aliases... Loading kernel from flash ....... done Loading ramdisk from flash ............... done blob version 1.0.0, Copyright (C) 1999 Jan-Derk Bakker and Erik Mouw. blob comes with ABSOLUTELY NO WARRANTY; read the GNU GPL for details. This is free software, and you are welcome to redistribute it under certain conditions; read the GNU GPL for details. Autoboot in progress, press <enter> to stop ...', "", ""); erow(); ?>

If you don't press the <enter> key within 10 seconds, blob will automatically start the Linux kernel: Starting kernel ... Uncompressing Linux...done. Now booting the kernel ...', "", ""); erow(); ?>

However, if you press the <enter> key, you will get the blob prompt: Autoboot aborted Type "help" to get a list of commands blob> ', "", ""); erow(); ?>

Blob has quite some commands, typing help will show you which: Help for blob 1.0.0, the LART bootloader The following commands are supported: * boot [kernel options] Boot Linux with optional kernel options * download {kernel|ramdisk} Download kernel or ramdisk image to RAM * flash {kernel|ramdisk} Copy kernel or ramdisk from RAM to flash * help Get this help * reload {kernel|ramdisk} Reload kernel or ramdisk from flash to RAM * reset Reset terminal * speed Set download speed * status Display current status blob> ', "", ""); erow(); ?>

Have a look at the blob distribution for more information on the commands.

Getting blob

Get your copy of the blob source here:

Or get a precompiled version:

The blob CVS tree is hosted at SourceForge.

Download utility

Richard Green got fed up with the tedious process of sending files to his LART and wrote a tool to `scratch his itch.' He has released it, free of charge & guarantees, so here it is:

Questions

Questions about blob should be asked on the LART mailing list.