Sm-g920f Nv Data File Best -

1. What is the NV Data File?

NV = Non-Volatile memory.
The NV data file contains device-specific calibration and configuration data stored in the EFS (Encrypted File System) partition.

Common Myths Debunked

“Flashing stock firmware fixes NV corruption.”
No. Stock firmware does not overwrite the EFS partition. If NV data is corrupted before flashing, it stays corrupted after.
“A custom ROM can restore my IMEI.”
No. ROMs only touch system, data, and cache. EFS/modem partitions are untouched. sm-g920f nv data file
“Factory reset will fix ‘unknown baseband.’”
No. Factory reset clears user data, not hardware calibration. The issue is one partition deeper.

Part 7: Post-Restoration Steps – What to Do After Writing NV Data

Simply writing the file is not the end. You must also: “Flashing stock firmware fixes NV corruption

Update Baseband (Modem) Separately: Download the latest modem firmware for SM-G920F from SamMobile or Frija. Flash only the CP file using Odin. This ensures the NV data matches the modem driver version.
Perform a Factory Reset from Settings (not recovery). This rebuilds the efs symlinks.
Test All Bands: Install an app like "Network Signal Guru" to confirm LTE (Band 3, 7, 20) and 3G connectivity.
Make a New Backup NOW: Using TWRP, back up the EFS and NV partitions. Copy this backup to your PC and cloud.

Method B: Using Chimera Tool (Recommended for Most)

Step 1: Install Chimera Tool and purchase a 24-hour license ($~20). Step 2: Boot SM-G920F into Download Mode. Step 3: Open Chimera Tool → Select Samsung → SM-G920F. Step 4: Click "Read PIT" to confirm connection. Step 5: Navigate to "Repair" → "NV Data" → "Write from File". Step 6: Select your downloaded NV Data file. Step 7: After write completes, go to "IMEI" → "Change IMEI" (using your original IMEI printed on the phone’s back or box). Step 8: Reboot. Dial *#06# to confirm.

Anatomy of the G920F NV Data File

On the SM-G920F, NV data resides in the EFS partition (/dev/block/sda5 or similar, depending on the firmware revision). When backed up via tools like TWRP or Octoplus, the resulting file is typically named: “A custom ROM can restore my IMEI

efs.img (full partition image)
NV_data.bin (extracted modem NV items)

Inside, the file is structured as a series of NV items – indexed parameters (e.g., NV item 550 is the primary IMEI, NV item 851 is the Bluetooth address). Each item has a header, length, and raw data.

Using a hex editor or specialized tools like Revival or NS Pro, one can manually edit NV items—but this is risky. One wrong checksum, and the modem rejects the entire file.

Method 1 – Root + Terminal (Recommended)

su
dd if=/dev/block/platform/15570000.ufs/by-name/EFS of=/sdcard/efs_backup.img

Or copy entire /efs:

cp -r /efs /sdcard/efs_backup

Method 3: Manual ADB (For advanced users)

su
dd if=/dev/block/platform/155a0000.ufs/by-name/EFS of=/sdcard/efs.img