This is a VERY EARLY BETA! It does function, but its rough. Don't expect this to be smooth or easy yet.
This image is based on Amon-RA-v1.6.2
What you need to do:
This hack will boot a rom from SDCard. It expects to see system.img and data.img on the sdcard as well as init.rc.
System.img needs to be a disk image of a filesystem that the kernel can read(I've been using ext3) around 170MB(Thats the Eris's NAND size for system)
data.img needs to be a disk image of a filesystem that the kernel can read(I've been using ext3) as big as you'd like your data partition to be(This holds your apps etc, so a couple hundred megs is good)
init.rc needs to be the init.rc of your rom with two changes
You need to remove the lines where it mounts /system and /data.
Once you have those three files on your sdcard, and have flashed this recovery you're ready to try your first boot.
Reboot into recovery, you'll see the normal usual recovery menu(I'll add an item eventually)
connect to the recovery console with adb
run 'adb shell /bootfromsd'
It will APPEAR to have done nothing for a bit, this is normal. Its booting your rom now. Once it gets to the place in the rom where it would display the splash screen, you'll get a splash as usual. You can watch it with logcat if you like.
I've personally booted the following roms from SD.
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