The ADMA (Advanced Direct Memory Access) is a driver for managing the communication between your computer and the SD (Secure Digital) card. This mechanism allows you to transfer data quickly and easily. However, in some situations, using this setting can damage your memory card and lead to critical data loss situations. In such circumstances, you need to look for SD card recovery solutions to get your precious data back.

Consider the following scenario

You have an SD card, which is formatted with the NTFS file system. It uses ADMA to transfer data between your memory card and the computer, which is running Microsoft Windows 7. However, when transferring data via this method, the logical structure of the memory card and the data on the card may be damaged. Furthermore, unexpected issues may also occur when you try to use the corrupted memory card or data.

Fundamentals of the problem

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

The maximum size of the data length field is 64 KB (Kilobyte) and its value is 16 bits. However, when you continue the data conversion procedure, the Sdbus.sys drive does not check the buffer size in your Windows 7 system descriptor table. Therefore, the Secure Digital bus driver can set a data length wrong in SD descriptor table. For example, the Sdbus.sys drive may set a data length greater than 0xFFFF. In this scenario, input/output errors can also occur. All this behavior leads to serious data loss situations.

Solution

To avoid such situations and the need for SD card recovery, Microsoft provided an update to fix memory card corruption issues in Windows 7. But if your data is already lost, then you need to restore it from the latest version.

In case the back is not up to date or not available at all, SD card recovery software is required. The apps methodically scan the entire SD card using high-end scanning algorithms and extract all the lost photos, songs and videos. SD card file recovery apps have a self-descriptive user interface to provide ease of use. With read-only and non-destructive behavior, 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 is compatible with all major cameras such as Nikon, Canon, Kodak, Sony, Fuji and Olympus.