Flash memory cards are now in widespread use. This method of storing information is much more convenient than other alternative options, which explains its popularity. The absence of moving parts, high speed, long life - this is not a complete list of the advantages of flash drives. Moreover, if the card reader does not see a memory card, then at first it is hard to believe. The main thing is not to panic and calmly try to restore working capacity. There are several reasons why the card reader does not see the memory card. In this paper, we give their description and recommendations for elimination.
A card reader is a device through which you can work with flash memory cards. It performs two functions: recording (including formatting) and reading information. Inside is a controller and a group of sliding contacts. Card readers can be either internal embedded or external. By the way, mobile phones that use memory cards also have their own card reader. Therefore, if such an integrated card reader does not see the memory card, then you need to look for the reason in it, and not in the phone.
Currently, the market offers a wide selection of different types of flash memory cards: SD, miniSD, MMC, xD, etc. Between themselves, they differ in the number of contacts involved and their location, shape, speed and level of energy consumption. In some cases, the differences are more trivial - dimensions. So, often using the simplest adapter, you can use SD cards in devices for MMC. It is not surprising that users sometimes have to figure out why the card reader does not see the card. After all, cards have their own characteristics.
One of the most common reasons why a card reader does not see a memory card is the incompatibility of standards. The specification for any card reader (even built-in) always indicates the supported types of flash cards. Unfortunately, the reality is that instructions are almost never read. Many people think that if the card goes to the reading device connector, then there will be no problems. This is not true. For example, there are currently two types of SD (Secure Digital) standard cards: standard SD with a maximum capacity of 2 GB and its advanced SDHC (Secure Digital High Density) modification. The capacity of the latter can be 32 GB. They are identical in size and arrangement of contacts! The difference lies in the mechanism of addressing memory pages: in SD - byte-by-byte, and in SDHC - sector-by-sector. If you insert an SDHC memory card into the device for SD, then it will not be possible to work with it. Either it will not be determined at all, or there will be constant failures. Hence, if the card reader does not see the memory card, then you need to check that the device and card are compatible.
When using an adapter (SD - MMC), it is necessary to check the status of the contacts using a flashlight. Sometimes, even with careful use, the internal spring-loaded contacts in the adapter “break” with an inserted card. In this case, you need to change the adapter.
If there are problems with the health of the computer, you should check the status of the BIOS settings. USB ports must be enabled (Enabled), and if the function is provided, then in USB 2.0 mode. Also, if "Legacy USB" is present, then it must be activated. In any case, when connecting the card reader to the computer, the icon for safe removal (for Windows) should appear in the system tray next to the clock. If it is missing, then you need to temporarily disconnect the extra USB devices and check the card reader. And finally, make sure that it is working on another computer. You may need to change the device to a newer version.