Didj Lightning Boot Options

Summary
There are several versions of Lightning Boot you can install on your Didj, This page gives a run down of each of the options, and how to use them.

Hardware Needed
Console Access

Software Needed
Lightning Boot

SD Card Configurations

 * Version 1.4
 * SD Formatted with FAT filesystem.


 * Versions 1.6+
 * First partition as FAT, large enough to hold a zImage, Lightning Boot, U-Boot, etc.
 * Second partition as Ext3, large enough to hold a Rootfs, and anything else you'll want on there.

Load from NAND normally
Choosing this option, boots the Didj as if it was in stock configuration.

The Didj has two sets of Kernels and Rootfs to boot from, which one is chooses to boot from can be set in the /flags/rootfs file. There are two options to choose from RFS0 and RFS1. You can manually update this file if you like, to switch between them.

 Version 1.6+  This feature was modified, so that it will always use the kernel0, only the Rootfs will change.

Download via Xmodem @115200
This option allows U-Boot to be downloaded via Xmodem with console access.

You'll need a terminal program that can send files with Xmodem. Get your terminal program connected, and make its ready to go. Turn the Didj on, and select this option. Go back to your terminal program, and send u-boot.bin. You will then need to hit any button except power on the Didj, and it will accept the file for download. Once transferred, it should start loading, and you will have console access to its features.

Load u-boot.bin from SD
This option will load u-boot.bin off the SD card FAT partition, and run it. Once booted you can access the U-Boot features from your console.

Load zImage from SD
This option will allow you to boot a kernel zImage file from your SD card FAT partition. Then depending on how your kernel is configured, it will load the Rootfs from where its been configured to find it, stock is NAND.

Boot from NAND with SD Kernel and Rootfs
This option allows you to boot your kernel and rootfs off an SD card. The kernel should be on the FAT partition while the rootfs will be expanded in the Ext3 partition. There are two commandline boot options to choose from, which can be selected by changing the /flags/rootfs file, to list either RFS2 or RFS3. Using the RF3 option adds in debugging, which makes for more verbose output in the console.

Boot from NAND with custom cmdline
This option allows you to boot the kernel located at kernel1, using a custom boot cmdline read in from a file on the FAT partition on the SD card, the file is called 'cmdline' and can contain a cmdline with max.255 chars.

autoboot zimage from SD
This option allows the user to autoboot a kernel zImage from SD, removing the need for user intervention.

To use the feature simply create an empty file called autoboot on the FAT partition, Lightning Boot will automatically boot the zImage from SD, to disable this feature simply delete the file.

Load Lightning Boot from SD
This option is good for Lightning Boot development work. You start the Didj up to the boot screen, then choose this option, it will load another Lightning Boot off of SD and run it. The file on the SD card must be named lb.bin. A warning though, you can't keep loading Lightning Boot over and over again. You can do it once, then you will have to turn the Didj off. As it will start trying to write over itself and crash.

Set Default Boot Option
This option uses a file on the SD card that allows you to set the boot option you want it to automatically use.

This requires a file on the SD card named autoboot, which contains the number of the option you want to automatically trigger.