Flash Drive Data Recovery educational webinars

Flash Drive Data Recovery educational webinars

Chip-off NAND data recovery with Visual NAND reconstructor consists of several essential steps whose task is to reverse transformations which controller applied on user data. In those education webinars, you will find out how to extract raw dumps from NAND memory chips, how to correct them using written ECC codes, how to assemble blocks into a logical order, and much more.

Chip reading, ECC usage, Page layout, Dump reread, Read Retry.



00:00 - VNR case types
01:34 - NAND chip and NAND adapter types
05:55 - The configuration
08:17 - ID reading. Configuration selection
16:45 - Configuration test. Data quality test
28:52 - The Voltage control
38:34 - How to select a configuration if there are several of them. SDR and DDR protocols
47:16 - ECC
58:43 - PAGE structure
01:03:11 - Case study. Phison controller ECC applying and Page layout setting
01:17:07 - ECC codeword test
01:22:19 - Case study. SM controller ECC applying and Page layout setting
01:25:02 - Case study. AU controller ECC applying and Page layout setting
01:28:40 - Case study. Sandisk controller ECC applying and Page layout setting
01:31:08 - DUMP rereading. How to fix uncorrectable by ECC pages.
01:43:03 - Read Retry

The link to PDF presentation: 
https://drive.google.com/file/d/1E_pQCj5ZSAgV60XgCllVnw6Lp85kJkIB/view

Bad Column Remover. Case studies. 



00:00 - New automated Bad Column Remover
10:27  -  Phison controller bad columns removal
45:58  -  SM controller bad columns removal
56:34  -  AU controller XORed bad columns removal
01:02:06 -  Unknown controller 283 bad columns removal

The link for the test cases:

Page structure analysis and reverse engineering of BCH codewords from unsupported devices.



2:03 - NAND page structure
12:03 - Manual Page layout setting in VNR
46:41 - BCH codeword
55:10 - Manual BCH codeword detection
1:06:34 - "Codeword analysis" usage, BCH codeword Bruteforce
1:18:50 - Case study. Manual PAGE layout setting and BCH codeword detection for SM controller
1:24:26 - ECC size and position detection in fully XORed page
1:34:50 - SM service area ECC detection
1:43:32 - Case study. Manual PAGE layout setting and BCH codeword detection for AU controller
1:54:50 - Case study. Manual PAGE layout setting and BCH codeword detection for SanDisk controller

The link to PDF presentation:
https://drive.google.com/file/d/1JSubQgCmYlLgMQXgeLARCo7mez47OVXo/view 

Inversion. Data transformation analysis. XOR, XOR analyser.



1:41  - Inversion
5:19  - Scrambling (XOR)
8:28  - Inversion detection. Data transformation analysis
14:58  - Case study. Inversion is not used
24:42  - Case study. Inversion is used
34:05  - XOR analysis. XOR analyzer
1:07:52  - Case study. XOR transformation elimination. SM controller
1:17:32  - Case study. XOR transformation elimination. AU controller
1:21:50  - XOR key extraction from a patient dump (overview)
1:24:35  - Case study. XOR transformation elimination. SanDisk controller
1:29:59  - Phison dynamic XOR
1:32:47  - Case study. Dynamic XOR transformation elimination. Phison controller
1:36:13  - Logical block size check and adjustment
1:44:39  - "Adjust key to page layout" explanation

The link to PDF presentation:
https://drive.google.com/file/d/1ENuoGtkGmoOjVlUtKvLqIVf83714Yi80/view

XOR key extraction from the dump. XOR key adjustment. XORed SA.



0:33 - Data Scrambling (XOR) 
1:18 - Descrambling (XOR elimination)
2:30 - XOR key selection
4:41 - XOR key extraction
24:19 - XOR key types
28:52 - Adjust key to the page layout
31:58 - Case study. XOR key extraction, Phison controller
34:20 - Number of Xor keys in one block determination
44:26 - Case study. XOR key extraction, SM controller
46:09 - XOR key signature
 58:54 - Existing XOR key from database fitting. XOR key size adjustment.
1:05:54 - Extract Area tool
1:09:46 - Case study. XOR key size adjustment. SA XOR key extraction. 
1:17:41 - SA XOR key extraction

The link to the PDF: 
https://drive.google.com/file/d/1joQhQktnvwoOQuTIzYMZg1ADvjkHB0KC/view

Multi-Plane page allocation. Pair and Unite usage.



1:21  - NAND memory internal structure
2:51  - Page allocation modes
10:34  -NAND chip block reading/ the reason of page mix in a dump
11:52  - Single-plane page allocation in a dump
12:33  - Multi-plane page allocation in a dump/ PAIR element
17:27  - Multi-plane page allocation detection
25:46  - Multi-plane page allocation on the chip level/ UNITE element
39:05  - Case study. One dump. PAIR is used.
53:15  - Case study. Two dumps. PAIR is NOT used. Unite by DUMPS is applied.
1:00:22  - Case study. Two dumps. PAIR is used. UNITE by PAGES is applied.
1:12:04  - Case study. Four dumps. PAIR is used. UNITE by PAGES and then UNITE by DUMPS are applied.
1:21:51  - Case study. Four dumps. PAIR is used. UNITE by PAGES is used.
1:26:27  - Order of dumps for the UNITE detection

Link to the PDF presentation and test cases:
https://drive.google.com/file/d/1919HV4o7-ZN8pGpNLg4GM1mPcwmYi72L/view

Block management. LBN, headers, Marker table.



0:00  - NAND Data recovery process review
5:26   -  Block management explanation 
12:55  - The Header
20:25  - The Logical block number
25:15  - Inverted LBN
27:26  - LBN Little-endian order
29:03  - The LBN and header location in the service area.
32:15  - Block management step-by-step script
37:07  - NAND Data recovery case step-by-step demonstration in the VNR
39:25  - BCH element usage in the VNR
41:53  - Page layout determination
46:06  - XOR analyzer usage
48:39  - Multiplane page allocation. PAIR element usage
51:20  - PS2251-50-F Block management
52:19  - The LBN and header search in the SA (Phison controller)
1:04:22 - Filtering by Header (Phison controller)
1:09:07  - Filtering by LBN range
1:13:21  - Duplicated blocks
1:18:26  - Missing blocks
1:22:18  - SM3255QAB Block management
1:24:28  - The LBN and header search in the SA (SM controller)
1:30:29  - Inverted LBN
1:34:48  - Filtering by Header (SM controller), Header range determination
1:45:38  - AU6983 Block management
1:52:00  - Banks
2:08:12  - SM321QF AC Block management
2:09:35  - Can't see the header and LBN precisely
2:24:33  - LBN little-endian order example
2:33:36  - LBN chain check
2:43:08  - Particular file block number detection
2:45:54  - AU6989SN Block management
2:49:24  - XORed bad columns removal
3:01:44  - Correct data block selection when there is no header
3:08:12  - Non-standard LBN chain test step
3:17:24  - SM325AC Block management
3:21:44  - The Mask usage

The link to the PDF presentation:

    • Related Articles

    • Silicon Motion(SM) controllers - Data recovery

      We can find plenty of NAND controllers on the market and without any doubt one of the most popular is SiliconMotion.  These controllers found their use in all kinds of flash devices, starting from USB flash drives, SD cards, monolithic devices, and ...

    • Alcor Micro(AU) controllers - Peculiarities of data recovery

      Alcor Micro (AU) controllers are found in all sorts of devices such as microSD cards, USB flash drives, SD cards of any package, and especially monolithic devices. They are very popular in cheap, refurbished, and fake devices as well. Recent models ...

    • Binary patterns in NAND flash memory

      Analysis and recognition of binary patterns in NAND flash memory is the key step in chip-off data recovery and digital forensic analysis of broken flash devices. This analysis is carried out in the Bitmap mode since the classic HEX view does not ...

    • Missing data planes in TSOP48, LGA52, BGA132 and BGA152 Sandisk chips.

      This article shows the way how to extract all data from TSOP48, LGA52, and BGA132/152 Sandisk memory chips when the configuration and dump size are correct, but half of the dump is still empty.  Usually, if a NAND memory chip has 2 or 4 crystals, ...

    • ECC in NAND flash memory

      All modern flash storage devices have a problem with data integrity caused by a poor quality of the NAND chips. This problem is well known as “Bit errors”. When bit errors appear within the area where file is stored, it gets corrupted and unreadable. ...