SWDL commands
In /extbin/swdl/ is possible to create empty folders as SWDL commands:
clamp_30_protection = probably stop watchdog (created during update)
mmc_update_marker = probably update process (created during update)
mmc_wait_sync_marker = probably update process (created during update)
drwx------ 2 root root 512 Feb 01 07:04 clamp_30_protection drwxrwxrwx 2 root root 512 Jan 01 1970 mmc_update_marker drwxrwxrwx 2 root root 512 Jan 01 1970 mmc_wait_sync_marker
I had unit stucked on update screen. In /extbin/ were folders apps (full size) and apps.bak (just some MB). I guess that after removing mmc_update_marker and mmc_wait_sync_marker and restart, unit deleted full size apps folder and moved apps.bak to apps. So unit is writing on serial that some libraries are missing and I have black screen with no telnet. Unit is not restarting because I kept clamp_30_protection in extbin (probably mistake). So I guess there is only way to fix it by reading emmc.
In metainfo2.txt is part where is EXTBIN_APPS.bin extracted into /extbin/apps_bak/ so I think it's related. But someone who knows more can fix the information.
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