Originally Posted by Poetcop
Hope this doesn't stray too far from the point of this thread, but has anyone succeeded in compiling the fastboot tool for Windows? MfgTool works only for Windows, and I only have fastboot for OS X, so I have to keep rebooting to go between them...
Something weird about this black screen mode: when the battery runs down (which it seems to do fairly fast in this mode), it displays the "plug me in" symbol, but more importantly mounts an (inaccessible) USB drive, just as it did before the blackness descended. Just some clues I'm pondering.
Yifanlu's kindle fastboot can be compiled to run in a cygwin shell in Windows.
When the battery is low, u-boot runs in low-power mode, with SDRAM and mmc turned off. It runs just enough to recharge the battery. In this mode, it exports a 0-byte USB "Fake Storage" device, to prevent the host PC "green" mode from turning off the power to that USB port. In u-boot this is called "fstor" mode.
When the battery has charged enough, it will change modes.
You can read the GPL source code to learn more about how this works.
By monitoring the serial port messages while recovering my K4NT, it appears to charge quickly when in fastboot mode.
I recommend booting a bricked kindle to fastboot mode to recharge the battery.