New Client Portal and Software update 19 Nov 2014

New Client Portal and Software update 19 Nov 2014 The first major update is released! We have launched new Client Portal where all Visual Nand Reconstructor users can get new software updates and resources of VNR. Here’s what we added in new VNR software release New software New element “BCH” with function of universal ECC decoder…

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Binary patterns in NAND Flash memory

Binary patterns in NAND Flash memory The Physical image of NAND contains following recognizable patterns Data area patterns Scrambled (XORed) data area patterns Spare area patterns ECC patterns Bit error patterns Bad Columns patterns Other patterns Data area   The Data has quiet high density (entropy) and has horizontal patterns that look like stripes, cubes,…

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Scrambler pattern (XOR key) visual recognition

Scrambler (XOR key) pattern visual recognition AU6990 / ITE1171 / PS3016-P7-T / FC8708-C / PS2251-33BA / ITE1167BFN-46A / IT1165E-48B / PS2251-33BB-E Pattern (XOR key) period: 128/256/258 pages Page size: 8kb Visually looks like diagonals. Controller generates one page of pattern for first page in block, then cyclically shift it -1 byte (-8 bits) for next…

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Analysis of bit errors in NAND and power adjustment

Analysis of bit errors in NAND and power adjustment During the NAND chip reading process (physical image extraction) there are internal noise and interference occur, that results to bit errors and data corruption. This problem is particularly critical for TLC flash chips. If physical image extracted with high number of bit errors, the correction through…

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Direct access to NAND and physical image extraction

Direct access to NAND memory and physical image extraction The Visual Nand Reconstructor supports two modes of access to memory chips: 1. Direct access to NAND memory (used for scrambler (XOR key) extraction, bit errors estimation, bad columns removal, power adjustment) 2. Physical image extraction (used for logical image reconstruction and data recovery) When new…

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Logical image reconstruction

Logical image reconstruction When physical image of chip extracted to file it’s stored in “Physical image” element. In this case pendrive had one NAND chip that consisted of one crystal. At beginning of analysis it’s necessary to describe structure of NAND physical image. It helps to visualize patterns and determine parameters such as Block size,…

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