Fun fact: The D820/D821 KRT16M modems have matching md5 sums. They are the same modem.
This means D821 users can just flash the D820 modems.
No, flashing a different modem will not change your available phone bands.
To dump your modem to the root of your internal sdcard: su
dd if=/dev/block/platform/msm_sdcc.1/by-name/modem of=/sdcard/modem.img
D821 KRT16M (4.4)
by QUALCOMM, Incorporated Oct 11 2013
The Nexus 5 has no built in EFS backup partitions. EFS contains things like your MEID or IMEI... your data profiles.. radio settings. The EFS cannot be replaced... it is unique to your phone only... backing up your OWN EFS is highly recommended.
Update: dees_troy has added EFS backup into TWRP. This does not make my zip obsolete... but the EFS is getting backed up the same way. My zip backs up the 2 EFS partitions and packs them into a flashable zip which you can restore in any recovery. TWRP backs up the EFS just like it does Data, Boot and System.
I want to point out... if using TWRP to backup EFS... try to have an original backup and save that off the device somewhere. Down the road you may end up with lots of EFS backups(if you backup via TWRP each time) and somewhere along the line you could mess your EFS up.. perhaps worse over the course of a month. If you get into the habbit of only saving your most recent EFS backup... that recent EFS backup may already be partially damaged. I'm not saying don't make frequent backups.. just have the very first one tucked away somewhere. DO NOT RESTORE TWRP EFS BACKUPS TO ANYTHING OTHER THAN THE ORIGINAL PHONE.
Backing up EFS
In TWRP, flash the Nexus_5_Backup_EFS.zip linked below. Nexus_5_Backup_EFS.zip creates a flashable zip backup of your EFS in /sdcard/EFS_Backup/. Please check to make sure the backup zip worked and actually made a .zip file. If you can't find it under /sdcard/EFS_Backup/... try /data/media/EFS_Backup/ instead.
Backup your efsbackupflashable.zip somewhere else besides your internal SD!!! Email.. cloud.. PC..
To restore your original EFS just boot into recovery and flash the efsbackupflashable.zip in your /sdcard/EFS_Backup folder.
If flashable zip wasn't created or to manually restore efs img files run the following commands using adb shell while in recovery:
dd if=/sdcard/EFS_Backup/efs1.img of=/dev/block/platform/msm_sdcc.1/by-name/modemst1
dd if=/sdcard/EFS_Backup/efs2.img of=/dev/block/platform/msm_sdcc.1/by-name/modemst2
So efs isn't getting backed up with regular twrp system, data, boot options checked? I'm guessing we keep the back up separate--just a "just in case" thing, am I right? In general, we should be able to backup, flash, and restore without ever losing efs, correct?
The Motorola Defy Mini is a relatively popular device, despite not featuring … more
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