Chip reading
Reading dumps from chips
Visual inspection of memory chip should precede plugging it to the Reader and adapters. Checking pins and pads is a mandatory process. Bent pins should be adjusted properly. In case of severe damage (e.g. broken pins or pads), physical image extraction becomes more complex. If important pin/pad is destroyed, it may be necessary to solder chip onto Monolith adapter.
The memory chip itself should be cleaned and deprived of any contamination. For BGA chips it’s recommended to use solder wick in couple with soldering iron and then clean the chip with IPA 99%. In case of TSOP chips, use solder wick to remove soldering alloy. In order to clean micro contamination on TSOP pins the fiberglass pen or brush can be used then IPA 99% should be applied. According to the package of chip, appropriate adapter should be selected.
(pin 1 & pin-point in the correct order)
The Visual NAND Reconstructor supports most models of chips of all major brands. There are specially designed adapters for
most of them. List of available adapters:
https://rusolut.com/visual-nand-reconstructor/nand-adapters/
Once the chip and adapter inserted, the Reader should be connected to the computer. If it's not, the VNR software will display the following error:
Monolithic devices/Non-standard packages
In case of devices that have unusual pinout and they are not supported via adapter's it's necessary to solder device to MONOLITH adapter according to pinout in our built-in database.
To open database go to 'Plugins' tab and then open 'Monolith pinouts'.
Chip configuration
When everything is set up correctly, the VNR should be opened and the Reader element will appear automatically.
(“!” indicates need for your attention, pointing mouse on icon display recommended action)
In order to read out the flash memory, retrieving ID number using “Read memory chips” function is necessary. Execution of this function should display tab with ID and number of Crystals (Dies, CE, layers, etc).
After execution of this function VNR display information. This is the good moment to check if chip is properly placed in adapter and adapter in reader.
If everything is correctly placed, simply click 'OK' and VNR start reading chip.
In case of invalid ID, the VNR will display a window requesting voltage adjustment.
If ID is not recognized, the following need to be checked:
If your chip is high capacity Micron BGA memory, BGA 137, BGA 107, it may be necessary to adjust voltage to 1.8V
Some chips sometimes require higher voltage. There was a case when Toshiba 0x983AA89276 worked normally with 4.0V only
Proper chip connection and alignment (some chips have to be cleaned several times)
Pin-points orientation (pin 1 location)
Usage of any VNR adapter does not require BGA chip re-balling, it is enough to flatten the surface of chip.
Another situation that may appear is that ID was red properly but there is no configuration file in database, like in example below.
In that situation make sure that you have properly connected database. Every checkbox should be checked and also make sure that you have the newest version.
When you are sure that your Database is properly connected and there is newest version, but this situation repeat, so there is probability that we don't have this device in database. In that case just create a ticket in Help Center according to Guidelines.
If everything is fine, software should display window (e.g. below) with chip ID, number of crystals and it's configuration.
This window contain of three sections:
Chip crystals and it's id's
This section allows to see how many crystals chip consist of and also it display ID's. In this case chip have only one crystal.
The ID number contains a set of bytes where first one is most important since it is vendor byte:
- 2C (Micron)
- 45 (Sandisk)
- 89 (Intel)
- 98 (Toshiba)
- AD (Hynix)
- EC (Samsung)
In case of noise, the random ID may appear (e.g. ADADADAD; FFFFFFFF; 54654324 etc). In this scenario the chip has to be cleaned better.
Database
ID goes automatically to this section and it's possible to select proper chip configuration.
Configuration
In this sections we can observe settings of memory chip.
In case of multiple configurations most likely the difference will be the protocol settings.
In this situation, appropriate protocol must be found. Set DDR protocol in the first order, open Dump viewer on reader and check the data in the Hex viewer to examine if there are duplication of hex values.
If bytes are duplicated like on picture, change protocol to SDR. If duplication of bytes doesn’t exist, then DDR protocol is
correct. Another step will be evaluation of chip quality in dump viewer.
Evaluating of chip reading quality
After successfully configured chip, checking the quality of the dump should take place, if possible. Clicking the "Dump viewer" automatically turn the Reader on.
Do not remove NAND chip or adapter out of reader until power is turned OFF or Reader is unplugged.
The Dump Viewer function allows examination of the data in 2 different modes.
The Hex viewer displays data in a traditional hexadecimal values.
The Bitmap viewer - represents the data in a visual binary form. It helps visualizing distribution of data areas, ecc, spare areas. The bitmap mode should be used for data quality examination.
With connected chip, the Dump viewer has direct access to NAND. In order to check the quality of data, analysis of the image must be done.
Now the image of the chip is being read on the fly and is not saved into file.
The next step is checking whether the dump is readable and contains acceptable
amount or no bit errors. Bit errors look like
randomly scattered bad pixels. Adjusting voltage level can be helpful here.
The detailed process of minimizing bit errors is described in this article. Analysis of bit errors in NAND and power adjustment.
Vertical stripes indicate problem with connection. It’s default response from the Reader if it didn’t receive any data from the chip. The value in Hex would be 30.
Chip
reading
When everything is done dump reading can be started.
To read dump, go to configuration and in crystal section select crystals and set how many chips you want to read.
After this click 'Read memory chips'.
Then VNR create physical image for each crystal and then start read the dump from each.
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