The ADMA (Advanced Direct Memory Access) is a controller to manage the communication between your computer and SD (Secure Digital) card. This mechanism enables you to transfer data quickly and easily. However, in some situations, using this configuration may damage your memory card and lead to critical data loss situations. In such circumstances, you need to go for SD Card Recovery solutions to get your valuable data back.

Consider the following scenario

You have a SD card, which is formatted using NTFS file system. You use ADMA for transferring data between your memory card and the computer, which is running Microsoft Windows 7. However, while transferring data through this method, the logical structure of the memory card and data on the card may get damaged. Furthermore, unexpected issues may also occur when you attempt to use the damaged memory card or data.

Grounds of the problem

During the advanced direct memory access transfer process, the Sdbus.sys (Secure Digital Bus Driver) converts DMA metadata structure of the Windows 7 operating system to ADMA metadata structure of SD card. The ADMA and the DMA metadata structures are also called descriptor tables. The descriptor table holds a buffer address and a data length value.

The maximum size of data length field is 64 KB (Kilobyte) and its value is 16-bit. However, when the data conversion procedure goes on, the Sdbus.sys drive doesn’t check the size of buffer in descriptor table of your Windows 7 system. Thus, the Secure Digital Bus Driver can set a wrong data length in SD descriptor table. For instance, the Sdbus.sys drive can set data length greater than 0xFFFF. In this scenario, the Input/Output errors may also occur. This entire behavior leads to severe data loss situations.


In order to prevent such situations and need of SD Card Recovery, Microsoft provided an update to fix memory card corruption issues in Windows 7. But if your data is lost already, you need to restore it from most recent back.

In case if the back is not updated or not available at all, SD Card Recovery Software are required. The applications methodically scan entire SD card using high-end scanning algorithms and extract all lost photos, songs, and videos. The SD card file recovery applications have self-descriptive user interface to provide ease of use. With read-only and non-destructive conduct, these applications are completely safe to use.

Stellar Phoenix Photo Recovery (Windows) is a comprehensive application to ensure successful recovery of all lost photos. The software works well with Microsoft Windows 7, Vista, XP, 2000, and NT. It supports all major cameras such as Nikon, Canon, Kodak, Sony, Fuji, and Olympus.

By lita

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