Connecting an SD card to Arduino. Why doesn't the phone see the SD memory card or USB flash drive? What to do? Connecting the memory card with internal memory
Starting with version Android 6.0, it became possible to use a flash card as internal storage device data. Now the device, after certain actions, can use the memory available on the SD as freely as the internal one. The article will tell you how to connect an SD card in this quality and what restrictions are imposed on it.
How to connect a flash drive as internal memory
Before connecting the drive, you must transfer from it all important information. During the setup process, it will be completely cleared and the data will not be returned.
First of all, you need to go to Settings, and then go to the section " Storage and Drive", where you should click on the SD card.
Next you need to select “ Tune" and click " Inner memory" Immediately after this, the device will warn the user that all information will be deleted and it will become impossible to read it on other devices without full formatting.
Here you need to select “ Clear and Format" and wait for the memory clearing process to complete. You may then receive a message indicating that the media is running slowly. As a rule, this means that the flash drive used is not very good quality and its use as device storage may also affect the performance of the smartphone itself. For good and fast work recommended to use UHS Speed Class 3 (U3) drives. 
After formatting is completed, the smartphone will ask you to transfer information, you should agree with this and wait until the work is completed. After the transfer, the work of turning the flash drive into internal memory will be almost complete; all that remains is to reboot the device. 
Features and limitations of using an SD card
There are a few things you should be aware of before you start using a flash drive in this way.
- After conversion, all data, except for some applications and system updates, will be placed on the SD drive.
- When connected to a computer, only this part of the memory will be available for interaction.
In fact, all actions are performed only with a flash drive, the real internal storage of the phone not available for interaction and is practically not used at all. Firstly, this means that when you remove the drive, almost all your data, photos and applications will be lost. Secondly, if the volume of the flash drive is less than the actual storage capacity of the smartphone, then the amount of available memory will decrease, not increase.
Format the card using ADB for use as internal storage
The function is not available on some devices, but it is possible to connect a flash drive as storage in another way. However, it is worth noting that this method is very labor-intensive and can cause damage to the device Therefore, if you are not confident in your abilities, then it is better not to do this on your own.
To use this method, you will need to perform many steps. You need to download from the site and install Android SDK, then download and install from the official website device drivers, and also, you need to enable “ debug modeUSB» on the device.
- adb shell
- sm list-disks (after execution, an id will be issued in the form disk:ХХХ,ХХ should be written down and entered in the next line)
- sm partition disk:ХХХ,ХХ private
Then you will need turn off the phone, go to settings and click on sd, select menu and click “ Transfer data" That's it, the actions are finished.
How to set a memory card to standard mode
To return the flash drive to standard mode you just need to go to its settings, as in the first option, and select “ Portable media" Before doing this, all important information should be transferred to another location, because the drive will be formatted in the process. 
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If your device does not have enough internal memory, can use SD card as internal storage for your Android phone. This feature, called Adoptable Storage, allows the Android OS to format external storage media as permanent internal storage. The information on the installed SD card is encrypted and cannot be subsequently used on another device.
SD Card is a very convenient option for storing photos, songs and videos. Even if you have a large amount of internal memory on your Android smartphone, you may always need a large chunk of memory to store long videos shot with the camera high resolution your phone.
It is important to know
There is one drawback, the SD chip can lag when recording high-definition video.
Android by default installs applications in the internal memory and only occasionally uploads data to the SD card. This way, you are prevented from installing any additional applications if your phone is running low on internal storage space, for example, in the case of budget Android One devices.
What is storage storage?
Storage storage is the main memory of your smartphone, but if necessary, it can be expanded using an SD card.
This on Android it is called Adoptable Storage. This will allow you to use a removable microSD card installed on your Android phone as your main storage. This way, you can easily solve the problem of how to make an SD card the main memory on Android and overcome the lack of space if the phone has a small internal volume.
Features of using the card as the main storage
There are a number of important features that should be taken into account during this procedure.
Will be useful
When using a storage device, be it an SD flash drive or a USB drive, it is important to remember what format the device is in and whether the Android operating system supports it, and there are four main file formats: FAT32 or exFAT, ext4 or f2fs.
How to change phone memory to android memory card? The question is not entirely correct, it is impossible to completely replace it, you can only “increase” additional volume.
Using your SD card as your main storage can be a great solution for music lovers and those who like to watch TV shows on the way to work or on a long trip. But, as often happens, memory expansion always depends on the cost of the required device, after all, they differ both in speed and in volume, as well as in the adaptable information storage function. Here are some nuances that you can consider with different sides– both negatively and positively:
- SD cards are slow. This is the painful reality of today's tiny memory chips. Even though they can store tons of data, they are slower than phone storage and have a limited number of read-write cycles.
- Permanent integration into the operating system. Using the Adoptable Storage feature, the Android operating system encrypts the external SD card used as internal storage, so it is tied to a specific device, without the possibility of further use on another smartphone. The key used to encrypt the data on the SD card is stored in the main memory of the Android device. Thus, it is impossible to remove the accepted storage to another phone due to its encrypted nature of the data (you can remove the card, but it will not be detected on another phone).
- Not all programs can be installed. Almost Android can install almost all applications on the internal storage. However, this also depends on the consent of the application developer. He has the right to enable or disable support for the accepted storage in the application by adding the appropriate attributes to the code of the downloaded program.
- Place the SD card on your Android phone and wait for it to be detected or displayed in .
- Now open Settings.
- Scroll down and go to the "Storage" section.
- Tap your SD card's name.
- Tap the three vertical dots in the top right corner of the screen.
- Click Storage Settings.
- Select the "as internal option" format.
It is important to know
Using SD cards as persistent storage will require more frequent read/write operations, which will degrade its performance over time, and in the worst case, may result in complete data loss. It will be especially offensive if there are important documents or treasured photographs or unique videos.
First, before you change the phone's memory to a memory card, your Android will do a performance test of the SD card to make sure that it is fast enough and can meet the parameters for use as a main drive.
However, you can remove the external removable storage from your device and revert it back to being a simple flash drive. The device will remember the settings that are on this card in order to restore the settings when the accepted device is connected later. So you can also use another storage device.
It is important to know
Always make sure that you do not remove the default SD card during the unmount procedure, otherwise the storage media may be damaged.
How to use SD card as internal memory on Android?
How to replace the phone's internal memory with an external SD card on Android? Configuring your SD card to act as internal storage on Android is essentially a fairly simple process. There is nothing complicated about this and you will see for yourself later.
note
Please note that your SD card will be formatted during the process. Don't forget to back up your data by temporarily transferring it to the main unit of your phone, desktop computer, laptop or other smart device.
It is possible that the Adoptable Storage function is not supported by your device, even if the smartphone runs Android 6.0 and higher (this can happen, it all depends on the model and brand of the smartphone). The device manufacturer may have disabled this feature. However, there are command line methods that allow you to force the use of a flash drive to store data.
Below are the basic formatting steps.
On the next screen you have one last chance to decide for yourself if you want to change your mind
Most modern smartphones are equipped with a memory card slot. Xiaomi is no exception. The presence of this function allows you to save important information on the device (music, photos, documents, notes), expand its capabilities and functionality, and also use the mobile device as an external storage device. When Xiaomi does not see the memory card, owners face some difficulties, especially if the phone was a way to store data for school or work.
What to do first
If you decide to immediately format the card or take the gadget in for repair, do not rush to do it. First, insert the SD into another device (tablet or computer) and check its operation. These simple steps will help you figure out whether the problem is with your phone or your removable storage device. Only after this can you choose a solution.
If possible, test another memory card with your smartphone; it is quite possible that both devices are functioning properly.
What could be the reasons for the breakdown?
Sometimes the violation may lie directly in the smartphone. To restore the functionality of the flash drive, copy the information to a computer or other device, follow these steps (depending on the situation):
- Crashes software smartphone. Remove and insert the flash drive back, reboot the gadget. System operation will be restored.
- Xiaomi does not support SD from some manufacturers or, due to its limited capabilities, cannot work with high-capacity drives. Study the technical parameters of the gadget; perhaps it cannot handle memory cards larger than 8 GB, but you offer it 32 GB. It is worth noting that sometimes correct operation is not possible due to the type of file system.
- Broken contacts in the slot. When Xiaomi does not see the storage SD card for this reason, remove the card and insert it back. If the problem occurs repeatedly, you should take the gadget in for repair. Fixing a breakdown takes a few minutes and is relatively inexpensive.
How to restore functionality
When an SD card fails, the following reasons can be noted:
- The flash drive memory is full. Remove it from your phone and open it on your computer, deleting extra files or by saving them on your computer. By freeing up space on the drive, you will restore the functionality of the device;
- Virus infection or incorrect file system format. You need to format it on your phone or computer. With this method of solving the problem, the data on the device will be lost.
To format using a smartphone, follow the following algorithm:
- go to the Menu and select the “Memory” section;
- select the “Remove memory card” or “Clear memory card” function and wait for the process to begin;
- After formatting is completed, the “Connect SD card” function will appear.
Depending on the Xiaomi model, the name or order of functions may change.
To format using a computer, you should adhere to the following algorithm:
- connect the card to the computer using a card reader;
- On your computer, open the “My Computer” section (the icon is located in the Start menu or on the desktop), select SD, which is usually displayed as a flash drive (or removable disk);
- pressing right click mouse on the flash drive, a menu will appear in front of you where you need to select the “Format” function;
- click the start button and wait until the formatting is completed;
- done, the memory card should restore its functionality.
A smartphone may not see SD for various reasons, and this is not always a serious problem. However, if none of these methods work for you, your best bet may be to contact a qualified repair professional. You should not disassemble the gadget yourself and try to repair it.
What to do if the phone does not see the memory card? Since I often get asked this and similar questions, I answered them all at once in this article. It will be useful to owners of cameras, Samsung, Lenovo phones, laptops - in general, all those devices that support a memory card and refuse to read the data on the card.
First, some technical details describing the problem. Let's say, as a result of some manipulations, a mobile device (phone, tablet, smartphone) stopped identifying a memory card (SD card) even through a card reader. All data is written to the internal memory of the phone, bypassing the memory card itself. This is inconvenient because the SD card is not used, while the memory of the mobile device quickly fills up. Productivity decreases accordingly.
So, the problem is described in detail, let’s move on to diagnosing the phone, smartphone, tablet. Let's look at the most common reasons why phones do not see a memory card (flash drive) and how to fix this defect on our own using a card reader.
The phone does not see the SD card due to an incorrect file system format or a damaged file table
Cause of the problem. 1) The file table on the SD card was damaged and the markings were lost. 2) You formatted the memory card yourself, as a result of which the phone stopped seeing the flash drive. 3) SD card file system is unknown (used in another operating system)
How to fix. 1. Find out the size of your flash drive. If the microSD capacity is greater than 32 GB, it is most likely formatted in exFAT. Not all Android versions support this file system. If you are not using Mac OS, format the memory card to NTFS or FAT.
I show how to do this in the video:
2. Fast way To fix the problem - reboot the phone in recovery mode and select the Wipe cache partition option in the Android service menu. This command will clear the contents of the SD card and format the media in the FAT32 file system - it is best suited for storing files on the phone.
Note. We would not advise inexperienced users to perform this procedure: if you mistakenly format the wrong partition, you will lose all the data on the phone, including files in the internal memory.
3. A safer (and more convenient) method of formatting an SD card is through a computer. You will need a card reader and SD Formatter software. It will help you format the flash drive properly.
4. You can try low-level formatting - however, not all manufacturers offer their own software for this (check the memory card website).
The memory card of the phone (tablet) has failed
Cause of the problem. As a result of mechanical / thermal damage incompatible with life, the phone stopped seeing the memory card or the SD card stopped working. Alternatively, the phone has stopped detecting the flash drive; on other devices the card is also unreadable.
What to do. Alas, nothing can be done with a damaged SD card. All you have to do is purchase a new SD card that is compatible in size and specifications with your smartphone or tablet. The most unpleasant moment is that all data that was stored on the memory card of an Android or iOS phone is completely lost. You will no longer be able to restore them - neither by connecting your phone with a flash drive via USB, nor through a card reader.
If the flash drive is still under warranty and looks like new (no visible damage), try returning it to the store. If you're lucky, you'll get a brand new replacement card.
Check for bad blocks (bad sectors) via HDDScan
The HDDScan utility (ignore the name) allows you to check memory cards, flash drives for bad sectors and read errors.
To diagnose the problem, it is enough to run the SD card through two types of tests - Read and Write tests. After spending 5 minutes of time, you will get a conclusion: are there bad sectors that prevent correct operation, which is why the phone does not read the flash drive.
- If the flash drive was purchased recently, we replace it under warranty (local or global).
- If there is no guarantee or it has expired, we erase the bad sectors with zeros. This can be done through the DMDE program. This procedure will allow you to shift non-working sectors, as a result of which the flash drive will be correctly detected both on the computer and on the devices where it was actively used.
Formatting with modern digital cameras
A number of Canon and Nikon camera models, according to user reviews, give positive results - they format at a low level.
How to fix an SD card through a camera:
- Insert the SD card into the device,
- In the camera menu, find the format command,
- Try recording files onto a formatted card.
Contact technical support (for Transcend flash drives, etc.)
Their technical support specialists can advise free of charge methods for restoring problematic flash drives. In fact, who, if not them, is best versed in the design of SD cards? In addition, technical support may offer you proprietary programs designed for low-level formatting (sometimes they are difficult to find on the manufacturer’s website).
Give the memory card to specialists for recovery
This option is suitable if you are willing to pay for the work of specialists. This procedure is expensive, but the advantage is obvious: data can be extracted from a faulty device (though only if the memory chips were not damaged).
The memory card is not compatible with the mobile device
Cause. 1) The mobile device does not support new memory cards. 2) The memory card is too large or uses an unknown technical specification. Therefore, the phone refuses to read the data and does not recognize the flash drive as a storage device.
What to do. Carefully study the documentation for your phone and buy an SD card that does not contradict system requirements.
Wrong data transfer mode in Android
Symptom. You connect your phone with a flash drive via a USB cable, selecting the Mass Storage option, as a result it does not appear on the computer.
How to fix. Instead of "Mass Storage", when connecting your phone to a PC, select the "MEDIA TRANSFER" option. Explorer should display the contents of the memory card.
The contact of the USB flash drive has come loose or the tracks in the socket have been erased
Symptom. As a result of displacement or incorrect connection, the memory card does not connect to the mobile device, and, as a result, the phone does not see its contents.
How to fix. Remove the SD card from the phone, insert it back so that the contacts of the SD card are correctly connected to the socket.
If the contacts of an sd flash drive are completely worn out, you can buy them for a couple of dollars and replace them yourself (of course, if you have the appropriate skills/minimum experience in repairing and replacing spare parts).
It is possible that the contacts (that is, the tracks on the board) on the phone have been erased, and for natural reasons it does not see the flash drive at all. A common reason is natural wear and tear of the phone. In this case, we recommend sending the device for repair or replacing the mobile device.
Software error, as a result of which the phone stopped seeing the memory card
Description of the problem. A certain Android program refuses to recognize the memory card. Other applications read the SD memory card and write data to the flash drive as if nothing had happened.
Solution. Android does not see the memory card, because the application settings indicate the internal memory of the smartphone/tablet as the storage source. Go to the settings of the application with which you are experiencing problems (for example, Android Gallery or camera) and specify the SD card as a successor - that is, the location where the files should be saved.
Instructions on how to check an SD card for errors (video):
Answers to readers' questions
After updating the phone (HTC desire 620 g dual sim) microsd is not detected, the flash card is constantly lost. It happens like this: for example, I’m listening to music, and then it stops playing and the phone writes: “the file could not be opened.” At the same time, the track names can be read. What could be the reason?
Answer . Check the audio file format. The player may not be able to read files of the selected format. So the problem is not necessarily a memory card reading problem. If the file format is correct, check the memory card for errors and format it.
I inserted an SD drive into my phone (Samsung galaxy j3 2016), transferred all the photos and videos to a flash drive, and all photos and videos were deleted in the phone gallery. The files are on SD, but all new photos are saved to the device’s memory. I need it to be saved to a memory card and displayed in the gallery.
Answer. If your phone does not see the SD card, try changing the path to the successor in the application settings. It would also be a good idea to check whether your phone and the Android system recognize the memory card itself. Just in case, turn off your mobile device, take out the SD card and put it back. Turn on the device and check if the files are saved to the Samsung phone flash drive.
1. The phone does not see the SD memory card (flash drive). An SMS arrived, I opened it, and suddenly I stopped seeing it. I rebooted and still can't see it. The laptop sees, the other phone sees. And most importantly, the phone sees another memory card. Smartphone brand – Lenovo 650. Please help! Thank you in advance!!
2. Does not read the memory card. I have Windows Phone Dual Sim 535. For a while my memory card was read, but later the phone stopped reading it. If you move it into other devices, it is readable, but not in mine, but if you insert other memory cards into my phone, then everything is fine. Why doesn't my phone see the memory card on my mobile device?
3. I cleared the phone's memory (fly), after which it stopped reading the SD card. The computer reads it, but the SD card is not detected on the phone. And it doesn’t see a single flash drive, I tried another card. (I probably deleted something unnecessary). Tell me how to correct the situation and why the phone does not read the memory card.
4. Prestigio phone. The phone stopped seeing the memory card. I was just sitting playing on the phone. Then I put it down for about 15-20 minutes. And when I took it, the notification “” came. I went into the settings - memory, where the External storage is. And there, instead of lines about how much memory there is, and how much the memory card on the phone takes up, there were only two lines.
- Connect SD card
- Clear SD card
I tried to press the first one and when I pressed it, the notification “Connecting an SD card.” And below this heading: “Checking errors” appeared for a second at the top (where the notifications are). And then a second later it was replaced by: “It’s safe to remove the SD card.” I tried rebooting, turning it off and on, removing and inserting the SD card. Same thing on another device. Why doesn't it see the flash drive?
5. Mobile devices do not see (do not read) the memory card. The memory card is new, recently purchased. At first there were no problems, but later the phone (philips s308) periodically did not read the map. The laptop saw it without problems. Soon the phone did not read the card at all, followed by other devices. The card does not contradict the system requirements. What could be the reason?What to do with it?
6. I have a tabletDIGMA OptimaI stopped seeing the flash drive after I cleared it in the settingsSDcard, restart, turned it on, took it out and inserted the flash drive back, nothing helped, I inserted it into another phone, I noticed it, but it doesn’t recognize it. What should I do?
Answer. If the phone no longer detects the memory card, you need to check this SD card on the computer via a card reader (the device connects to the PC via a USB cable and is inexpensive). In your case, the laptop has a built-in card reader. In order for a phone or tablet to read a card or USB flash drive, you need to correctly format it using WIndows or using special software. software We strongly recommend using the free SD Formatter program to format flash drives; this is a method we have tested and often works. We hope that after formatting, your phone will see the flash memory and will be able to write files to it as before. If the card reader still does not see the memory card, all that remains is to buy a new SD card.
I have a smartphoneSamsung Galaxy Gio S-5660. About six months ago I repaired the charging socket and haven’t turned it on since then until yesterday. It still contained a SIM card and a memory card. When I turned it on, it turned out that the smartphone did not see the memory card. Before this there were no problems with it. On the memory card there are contacts, books, a bunch of photos. Why doesn’t the tablet see the flash drive and how can I revive it?
I took the device in for repair and thought that the memory card slot was not working. turned out to work: new map sees it immediately.
Answer . OnSDthe card may have damaged pins or contacts (pins). If you do not notice any damage upon inspection, check the memory card for reading errors. Do not format it under any circumstances, otherwise you will not be able to recover the files.
I cleared “Phone memory-memory card” on the iPhone on Android, after which the SD card turned off. Below it says “Connect SD card”, I press it – but there is no effect. Now there is no memory (I took the phone apart, but there is no slot for a flash drive). All in all, mobile phone Doesn't see the memory card. Tell me how to return the SD card back to a working state?
Answer. If a working memory card is not visible on the device, the file table most likely contains errors. Try formatting the card using the sdformatter application. Since you are dealing with Android, the SD memory card must be formatted in Ext or Fat32.
Using the above application, I recovered photos on a Samsung SM-G 318H/DS. They remain in this application, I can’t transfer them to the gallery or to the SD card, how can I do this? Why doesn't it see the memory card?
Answer. Your question is formulated in a very florid way, so it’s difficult to say why the phone doesn’t detect the memory card. It looks like the problem is not with your phone's flash drive, but with something else. You need to copy the files to the DCIM folder on your device, then they will appear in the Gallery again.
I moved the SIM card from the tablet back to the smartphone and all the memory from the phone disappeared. What to do and whether it is possible to recover photos and contacts if the smartphone does not see the flash drive.
Answer. In your case, it's probably not so bad. You may have moved the SD card (flash drive), as a result of which it moved away from the smartphone socket. Check the connection between the slot and the phone's memory card. If contacts are missing on your smartphone’s flash drive, try importing contacts from the SIM card through the standard Android address book or synchronize contacts with your Google account.
Samsung Galaxy A5 2016 phone. Inserted a 2 GB Qumo SD card (new card, just purchased) into the second slot (for the second SIM card and SD card). The phone does not see it, either simply through the phone menu, or through a cable connection to a PC. What could be the reason, is there any way to “reanimate” the memory card?
Answer. Qumo memory cards don't have a very good reputation. However, usually 2 GB cards do not have problems when connected to a phone.
To begin, connect the memory card to the computer via a card reader. If the computer does not see the memory card (the disk is not displayed in Explorer), give the card (explaining that the computer does not see the SD card) to the seller and return the money.
If the SD card is not readable only on the phone, but everything is OK on the computer, try formatting the memory card by selecting FAT as the file system.
The Samsung Galaxy S5 smartphone has stopped seeing USB flash drives (previously it saw and read), the smartphone is almost new. Other devices, flash drives are detected without problems. Why doesn’t Android see the flash drive, how to fix the error?
Answer. There may be at least two reasons why the phone does not see the flash drive. Try to fix it like this:
1. Check if debugging is enabled on your phone (try enabling/disabling).
2. It is advisable to format the flash drive in exFAT, otherwise Android may not read its contents.
I dropped my phone and all the photos in the gallery in the camera folder disappeared from the memory card. Is it possible to somehow restore them? The remaining folders remained in their places.
Answer. Perhaps the SD card is damaged or Android does not see the SD card. Check if the SD card works if you connect it via a card reader to a PC. Another reason why the phone does not see the SD card is that the card has physically moved in the slot when dropped, so at the same time check the connection of the contacts.
As for the direct answer to the question: if the memory card is intact, you can restore the photo using any application, starting with CardRecovery and Recuva.
The problem is doubly unpleasant, because the phone was purchased a month ago. I decided to transfer some audio-video files from my old phone. The new smartphone is j7, and the old one is also Samsung Galaxy Grand Neo... The data transfer took place without any emergency situations.
About a week later I looked at the sd, and the card did not appear from my native “my files”. I looked through the RAR program, through the xplore file explorer. All the folders were displayed there, but they turned out to be empty. But it’s important to add this: the phone’s memory also contained music and some video. So, they were displayed, but they were not “empty”, but refused to be reproduced - “reproduction error”. This never happened on an old phone with any sd and different ages, it certainly happened, but not this. And this recorded card can be read normally on the old phone, no problems.
For me, the main thing is, as you understand, the question is the phone, is that the reason? Such refusals to read in a month happened twice with internal memory, and four times with sidishna. Reboot - and everything is fine. But is this not at all the norm for a phone?
Answer. There may be several reasons for this behavior.
Perhaps the cause of the error lies in your method of copying files from internal memory to external memory. Try different methods and test: for example, through a card reader on a PC, through a file manager on a phone, etc. Do the described reading errors occur in all cases?
However, since you noted that there are no problems with other flash drives, then perhaps the problem is with the memory card. Who is the manufacturer, is the SD card compatible with your phone model? Read user reviews.
Third, update the software on your phone and remove unnecessary applications.
Fourth - format the SD card using the SD Formatter utility. Try different file system formats.
1. Last chance to find an answer to my problem. The Samsung galaxy not 5 (china) phone uses only its internal memory, and the flash drive is not detected. What I didn’t do... I checked the boxes, and inserted it into another mobile phone, formatted it, and this and that - it doesn’t help.
2. On the phoneSamsung Galaxy A3 memory card does not workmicrosdvolume 16 GB. For almost six months it was on the phone; all photos from the camera were automatically saved on it. The memory card has not been removed since it was placed in the slot once. I've been using the phone for almost a year. Previously there was another card with a capacity of 8 GB.
R.SI moved the card to another phone - he doesn’t see it either. And the computer doesn't recognize it either. What to do? On the flash drive are all the children's photos and videos taken over six months.
Answer. If your smartphone or tablet does not see the flash drive, the problem may be with an application that does not save files where needed. Check in the settings where the files are saved - on an SD card, flash drive or in the internal memory of your tablet/smartphone. For example, in the Android Gallery settings you can change the storage location for photos.
Re-read the article. If all else fails, then perhaps the phone does not see the microSD memory card because it is faulty.
The phone does not detect the memory card. I transferred everything to internal memory. When the card is disconnected, all files are read, but when connected, they are not. Now, when you disconnect the SD card, the internal memory is also disabled and there is nowhere to save information. Tell me what can be done if the memory card is not readable (if possible).
Answer. Did the memory card work before this time? The phone may not support this card model.
If the SD card worked before, you may need to format your card - and it will be writable again.
The question is formulated incorrectly: you write that when you disconnect the memory card, the files are read, while you say below that the internal memory is turned off. So where are the files read from then?
1. The phone worked with a memory card. With the congratulatory video they sent a virus that could not be removed. You delete it and it appears again. I tried to reflash the phone, but it didn't work. It didn't detect any updates. After some manipulations in the recovery menu, it became different, detected updates, downloaded and installed them. It shows its own firmware, but with a more recent date.
After this, the SD card is not detected. Android does not see it and does not detect its memory. And other sd too. Without a card, the phone sees its memory and works fine. What to do if the phone does not see the SD card after a virus?
2. I put an SD card in the computer - everything reads well there, you can see. And the phone displays the message: SECURE REMOVE CARD. Why doesn't my phone see the memory card? What to do?
Answer. If the phone does not see the memory card, this may be due to damage to the file table on it. How this is related to recovery is unclear. Try formatting the SD card. If nothing changes in better side- change the firmware.
1. I bought a 4G micro flash drive for my phone, installed it in my computer via a card reader, copied the files and installed it in my phone (Microsoft Lumia 530). After some time, I installed it again in the card reader and connected it to the computer. Windows issued a message that the device is faulty and does not read the flash drive, but everything works fine through the phone. And this happens with all USB media and devices. I checked flash on many computers before installing it on the phone - everything was OK. After installation, the memory card does not work on the computer - only through the phone.
2. I ordered a flash drive forebay(universal flash drivei- flash device). I received it yesterday, inserted it into my phone - it works, it also works on the computer. Today I tried to transfer a video from my phone to a flash drive, copying started, I left the phone and went away. Upon returning, I discovered that the program was closed, and the flash drive was no longer detected on the phone, nor was the computer detecting it. What to do?
3. I bought a 32 GB flash drive for my phone from AliExpress. It worked fine, then the photos that were saved to it were half cropped or there was a gray screen instead. Eventually it stopped being detected by the phone. The computer seems to detect it, but does not tear it off. It says something like "insert disk". I tried a lot of things that were written on the Internet, a lot of programs. Some don’t see the flash drive, some see it, but still can’t format it.Tell me how to bring her to her senses.
Answer. Format the flash drive using your phone or Recovery (we wrote about this at the beginning of the publication. If this does not help, go to Windows Disk Management and check whether the flash drive is mounted when connected to the PC, whether the volume is displayed in the list. If necessary, you can create a new partition on the flash drive and format in FAT or extFAT using specialized programs.
I turn on music on my phone, it says: no music files. Nokia RM-1035 phone and mirex micro sd (HC) class 4, everything worked yesterday. Probably the memory card is not readable! How to find out if it is working or not?
Answer. Check if others can see mobile applications contents of the memory card, you can install another player for this. Connect the microSD card to your computer or laptop via a card reader. If the flash drive is not accessible in both cases, try other methods described in the article.
The Samsung Galaxy A3 2015 phone does not read the flash drive. I formatted it in all possible formats, but it didn’t help. Connected it to a PC - everything works great. Why doesn't my phone see the flash drive? Maybe something needs to be changed in the phone settings?
Answer. Go to Settings - Memory. Check the "SD memory card" section. Install a file manager and see if the memory card files are displayed on it.
In addition to standard formatting, you can try low-level formatting - however, not all manufacturers offer their own software for this (check the memory card website).
Another reason why the phone does not see the SD card may be the lack of contact between the memory card and the phone. Check if your device reads other flash drives. If not, take the phone to be repaired.
Phone Doogee x5. The phone didn’t see the memory card, but it was there. Data was transferred to external memory by accident. For some reason the transfer was completed, but the card was still invisible. Pictures, videos, music have safely disappeared somewhere. How to get them back and why doesn’t the phone see the memory card? Is it possible to restore all this somehow? I tried Android Recovery - to no avail.
Answer. If the phone does not see the SD card, then how did you transfer the files to it? Perhaps you simply copied them to another location.
Try connecting the memory card via a card reader to your computer and scanning it with CardRecovery. As for Android Data Recovery, this program is less functional.
After disconnecting the SD card for work in aparted and carrying out manipulations in it, the prestigio phone does not turn on the SD card again. By the way, the laptop does not see the memory card either. Actions in recovery did not help. What to do if the phone does not see the memory card?
Answer. Perhaps the operating system and laptop see the SD card, but the markings have disappeared. You need to create a volume on unallocated space. Start – Run – diskmgmt.msc. Find the unallocated area and use the context menu to create a new volume on the SD card, assign a letter, apply formatting. After these manipulations, the SD card disk should be detected as before.
I connected the camera as in the instructions (via a USB port), but the camera reads it as a Portable device, but it needs a Removable disk. The camera does not see the memory card in connected mode or what is the problem? How can I change the display? Camera Nikon Coolpix S9400.
Answer. Your camera supports SD, SDHC and SDXC memory cards. The computer does not see the memory card as a drive. You need to remove the card from the camera and connect it to your PC via a card reader. If you have a card reader built into your laptop, connecting the card will be even easier. After that, you will see the removable drive in the list.
mico sd 32G in an Android tablet. I distort the connector - everything is ok, but after a while the conductor does not see it and through the setup menu, the SD card memory does not turn on. If you take out and insert a memory card, it appears. I cleaned the contacts, wiped them with rectification, but still Android does not see the SD card where the dog is buried?
Answer. Try testing another SD card with your phone. If the situation repeats and the smartphone does not see the flash drive (the memory card disappears from time to time), then most likely the problem is in the phone contacts.
If another memory card works without errors, we recommend formatting the problematic card in FAT32 or exFAT - in case the phone does not see the micro SD flash drive due to errors in the file table.
The phone (Samsung Galaxy S5) does not read the memory card. I inserted three cards, and none of them are read, although they are displayed correctly on other devices. In this case, the inscription “Connect SD card”, the font of which was previously gray, becomes white and clickable, but if you click, nothing happens. All photos and pictures in the gallery (located in the phone memory) are not displayed. And applications that are not in the internal memory, but in the phone memory, do not open. Tell me what to do?
Answer. Possible level failure operating system Android or installed applications. Try to manually resolve the conflict by deleting all unnecessary applications from your phone. Update the OS version to the latest through the Android settings.
If the phone still doesn’t see the memory card, check the phone’s contacts: are there any visually noticeable damages on them?
Do you write "on other devices" when you mean a computer? If yes, it is likely that the file system of the flash drive is NTFS, and you need to format it to FAT or exFat.
When I insert an SD card into the phone, the device does not recognize it. No matter what I tried: even inserted it into other phones, I still can’t see or read its contents.
Answer. There is too little information about the memory card (virtually none) to give specific advice. First, check whether your phone supports SD cards of the size that is on your card (see the documentation for your smartphone or tablet). If you just bought a memory card, you can exchange it under warranty for another one of smaller capacity.
If you have previously used this memory card and it is no longer detected on this and other mobile devices, it is most likely faulty.
1. I cleaned the card on the computer. I deleted everything from it. Now there is a new smartphone teXet X-plus TM-5577. I inserted the Sidi card, he sees it, but nothing swings on the Sidi card and I can’t transfer anything to it. Tell me what to do?
2. The phone started to turn on on its own periodically (Lenovo A 526). Then I left the house and plugged in my headphones and noticed that not a single track was playing. Later, when I took out the phone, I discovered that the flash drive was not readable and the saved music did not play. I tried to reboot the phone - it doesn’t help, I put it in the card reader - it sees the memory card, I put it in a friend’s phone - too. But I don’t want it at all. And the most important thing that drives me crazy is the notification after turning on the phone with the phrase “Remove the MicroSD before deleting it so as not to lose data.
Answer. You need to connect the memory card to the computer again (as you did before), format the SD card in a standard way(for example, through Explorer) or using sdformatter. File system - FAT32. Most likely, it is due to incorrect formatting that the phone cannot write data to the memory card.
After a sudden shutdown, the tablet (Android 5.1) stopped normally recognizing memory cards in the card reader. It either writes, checking errors, or reads, which lasts indefinitely. At the same time, half of the programs stop responding, everything slows down wildly, and it becomes impossible to turn off the tablet (only when the discharge reaches 0 and turns it off). Sometimes (very rarely) after connecting, he sees it, but at the slightest manipulation with the card (even viewing a photo), he immediately loses it and begins to re-read it again, and this is the end. Tested on 3 flash drives, both clean and not, with different formatting and a lot of dancing with tambourines (all according to recommendations on the forums). A system rollback was performed. Nothing helped. He refuses to see the 8 gig card at all, although if you connect it via an adapter to the USB connector, everything works great (like other flash drives). What is the problem, in the card reader or in the system?
Answer. It is best to connect the problematic memory card to a laptop or, alternatively, via a USB adapter, as you mentioned. Next, the SD card needs to be formatted.
Most likely the issue is with the card reader. After a short time, many cheap card readers stop reading memory cards correctly and produce copying errors or read information slowly.
The system (Android) is unlikely to have anything to do with the problem, since you have already tested several memory cards. Perhaps it is a specific application that is slowing down the system, but this can only be determined by resetting the phone to factory settings.
Lenovo vibe shot phone, android 6. There is a 32gb sony sd card in the option as an extension of the main memory (ext4). The phone stopped seeing the file system - it says SdCard0 01/01/1970, 00 kb. Windows 7 sees two partitions - 16MB and 30GB, operational, 100% free each.
How can I return everything to its place by restoring the previous files? or at least how to pull out photos and the WhatsApp folder?
Answer. To recover a deleted partition on an SD card, R.saver or AOMEI Partition Assistant Standard Edition programs are suitable. If the file table on the partitions contains errors, you can try to fix them using the chkdsk utility for Windows. If that doesn't help, try scanning the SD card (unreadable sections) with the Recuva utility. Until you overwrite the information on the flash drive or format it, the chances of getting your files back remain high.
Samsung A3 2017 Samsung memory card 64 GB. I created folders from my computer: photos, ring notes, music, videos, movies, etc. The phone sees only audio, pictures, documents, video. Doesn't see any other folders on the memory card. What needs to be done?
Answer. Install any file manager for your phone (for example, Total Commander or ES Explorer). Create folders directly through these programs and copy everything you need there. Files should be read on the memory card without problems. It is also possible that those folders that cannot be read from the SD card are hidden or damaged. So it would be a good idea to format the card to avoid further errors.
Lenovo A2010 phone does not see the SD memory card. I tried to reboot, it says "Only one SD card is available, it is impossible to switch." Other phones do not have a card. It doesn’t show on the computer through the card reader at all. Is this really the end, so many photos and videos have disappeared? Maybe something can be done?
Answer. It looks like there are reading errors on the card or the markings have come off. Since the memory card does not open on the computer (i.e. the letter/separate drive is not displayed in the file manager), it makes sense to check whether the memory card is recognized as a device at all. To do this, go to diskmgmt.msc (Start - Run) and see if unallocated space appears when you connect the SD card to the PC. If it appears, create a new file volume in this space through the context menu. If nothing happens, most likely the SD card has failed.
Phone model sony xperia m4 aqua dual. For two years, a card was installed in the phone microSD memory. Recently, glitches began to occur: at first, in order for the memory card to work, it was enough to restart the phone. Now the phone has stopped seeing the map completely. Failed to format. Installed a new one. The phone recognizes it (it’s in the settings, photos were sent to the card), but applications cannot be downloaded from the play store (it still shows the option to download only to the phone’s memory). What needs to be done in this situation with a flash drive?
Answer. Format the memory card with specialized applications - the same SDFortatter is quite suitable. Next, check the card for errors using the chkdsk tool.
However, you clarified that changing the memory card does not help. The problem may be caused by specific applications or software conflicts within the Android OS. In this case, we recommend updating the firmware or, as a last resort, resetting the phone (execute hard reset).
After encrypting the SD card, Samsung A5 2017 stopped seeing it. Through the card reader on the computer it sees, but does not open. I tried to format (SDFormatter, cmd) - it doesn’t work. Sees other flash drives. I checked for errors - it gives an error, but does not correct it.
Answer. To check the SD card, use the following parameters:
chkdsk (drive letter): /f/r
- /f - fix file system reading errors
- /r - fix bad sectors on the sd card
This should fix errors and allow you to format the SD card in the standard way or through utilities like SDFormatter.
I have a Kingston DTSE3 16G USB drive, the computer doesn’t see it, the flash drive is unreadable. periodically the system displays a message stating that the device can work faster or the device is not recognized. Are there any recovery programs?
Answer. The flash drive supports USB 2.0 interface. Your computer (motherboard) may have more old version ports, which is why this message appears. Therefore, we advise you to update your PC hardware if you have not done so for a long time.
Recovery programs will not help you, but formatting the flash drive correctly (in NTFS/FAT) and then checking for errors using chkdsk will not hurt.
The Samsung galaxy tab 4 SM-T331 tablet does not see the SD card. available places 0b, free 0b. and I inserted the same SD card into another device, into my phone, and sees the SD card: available 14.57 free 14.57. I insert another SD card into the tablet - again it doesn’t see it, but the phone sees it.
Answer. If there are important files on the memory card, make a copy of them on your computer. After that, format the memory card and check it for errors. If everything is in order, you can use the SD card on your tablet or phone and write files to it. If the situation repeats, update the tablet firmware or perform a hard reset. However, this is already an extreme measure; we advise you to first deal with reading errors.
I made the memory card an internal storage device forZTE blade A510. After resetting the phone (SDthe card was in the phone all this time) it stopped working on all devices, Android does not save to it.
Answer . You need to format and mount againmicroSDas an internal storage. If the memory card is opened on a computer, transfer all the data on it to your hard drive.
I have a Samsung Galaxy S4 NEO.I bought a 16 gig memory card, but after 5 months of use it suddenly stopped seeing all the games that were on it. And the phone sees videos, photos and everything else without any problems. In settings > memory > memory card, the total volume, free space is written - in general, everything is as usual. Help with this problem!
Answer . The easiest way is to reinstall the games. This can be done through the applicationGoogle Play. If user data is still stored in the phone memory or onSD-map, games will work as before.If not, try restoring them through the appropriate recovery applications.
The SD card worked fine. Over time, the phone began to not see it, but after a reboot everything was restored. Now rebooting the phone has no effect. I connect it to the phone via USB and everything opens and plays. I rule out erasing contacts, since the phone is a year old and I rarely removed the card. Phone xiaomi redmi note 3 pro. Thank you in advance for your answer.
Phone LG LBello d-335. SD card size 8 GB. Previously there were no problems, but after I moved most of the applications to the SD card, the phone began to often show that it did not see it. After rebooting the phone, the problem disappears, but this happens very often. Please help me solve the problem.
Good afternoon I bought a new smart phone, installed the game, during the installation process the Android rebooted, after which the smartphone refused to read the SD card, that is, it does not see it, it seems like it is not in the slot. In another smartphone and through a card reader, the card is not visible. How to proceed?
Hello. The ZTE blade A 520 phone stopped seeing the flash drive, which previously showed everything without any problems. The CD card is displayed in the laptop through the card reader, but is not visible in the phone. I put in another flash drive, it can be seen, mine is not there. I took it for repairs, they fixed the input , but even after the repair it is not displayed on the phone, only through the card reader in the laptop. The card size is 32 GB. I don’t want to buy another flash drive, since this flash drive contains the main files, in general, everything you need. please help
We bought a new memory card. 4 phones don't see it. Tried on phones: Huawei Honor, Lenovo, Meizu, Samsung, Xaomi. Memory card 16GB. What to do?
Hello! I have this problem: for some reason it sometimes reads an SD flash drive (16 gig), but sometimes it doesn’t see the device. Can you help me why this is happening and what should I do?
The tablet does not see the SD card (16 gigs) after it goes into sleep mode, you have to open the back panel and reinsert the flash drive, and everything works fine, but again the next time you start it does not see the SD. formatted the card.
Hello, I wanted to ask if I have a problem with Samsung not 8, it doesn’t see the flash card before, but now it says connected and disconnected. I tried it on another phone, everything works fine and connects. Anything possible please help.
Hello, please help me figure this out. I bought a memory card for my phone, but it doesn’t see it at all, it just doesn’t respond to inserting and removing it. In the settings it says there is no memory card. We checked it in another phone, everything works. My other memory card can also be seen. The card is 64GB, according to the characteristics it matches my phone (maximum). We read somewhere that in such a situation you need to reset everything to factory settings, but will this help? I don’t want to lose all the data. Please advise what to do. Thank you in advance.
Good afternoon. I have almost the same thing, it doesn’t see the SD card, I formatted it but it says that the card is protected, the phone offers to format it, I agree, then I see it says it’s damaged, I check on the laptop all the contents are there and it’s still there... it doesn’t see it on the smartphone..
Hello, my SD card does not see the phone, I went into the memory card settings and it says prohibited, files are not displayed. When formatting an error is written. Is there any way to save the files?
I installed a flash drive on ZTE as internal memory. When I had to return the phone to factory settings, I pulled out the flash drive, and after all, I inserted it back and asked to format it, but everything was on it. They insert it into the computer and cannot see it. Tell me how to get photos from there into the computer.
The phone does not see the SD card. It does not open on the computer and asks to format it. There are a lot of important things to do on the card. How can you restore everything, not only photos but also documents?
I had an 8GB flash drive on my Asus smartphone. Then I installed it on the new Samsung A8 and it worked fine for two days. And then she stopped. That is, the phone does not see it. I tried to put it back on the asus. And he stopped seeing her. I bought a new one. Everything is fine. Samsung sees the flash drive, but again for two days. That's all. Disables flash drives. What could it be?
At some point, a notification came that the SD card was damaged. After that, neither my nor other phones see it. What to do? Are your files lost? How to restore them? There were a lot of necessary photos on it..
The ability to perform operations with the card disappears. I don't physically remove the card. In the MEMORY settings menu, I simply press “disconnect SD Card” and then immediately “Connect” and it is available for 15 minutes. After which again, although the card itself is visible, the file managers write “empty”, although the capacity is correctly determined as occupied/free. But nothing can be read or written down. When connected to a computer, not only the card but also folders/files are visible, but nothing can be done (read or write). Until the next one Disconnect/connect for 15 minutes. Cards of any capacity and class have been tried (new and formatted by both the computer and the device). If you constantly access the card, it will not turn off longer. It’s worth leaving that’s all.
We displayed the image on the display from an SD card, but some points were missed in it, the first was connecting the card itself, the second was that only part of the library’s functions was considered Petit FatFs, let's look at these points in more detail.
Communication with the card is possible via one of two interfaces, SPI or SD.
It must be said that the SD interface can operate in one-bit and four-bit modes.
The card connection diagram via SPI is standard and looks like this; unused card pins need to be connected to the power supply using a 10K resistor.
But in amateur designs, pull-up resistors are often neglected, simplifying the connection diagram.
It should be noted that when connected via SPI, the card is very demanding on the supply voltage and a slight drop in the supply voltage leads to the card being inoperable, this has been tested personal experience, I have nothing to say about the SD interface, I haven’t tried it yet. I wrote all this to mean that For power supply, be sure to install capacitors. As for the inductor, it should be designed for a current of up to 100mA, but it is not necessary to install it.
The diagrams shown above show that the card requires 3.3 volts to operate; accordingly, the voltage in the data transmission lines should not go beyond the range of 0 - 3.3 volts, and here the question arises, what to do if the MK is powered by 5 volts?
The answer is simple, you need to match the data lines, and this can be done using a conventional resistive divider.
The diagram shows that the MISO line does not need to be coordinated in the same way as data is transmitted via this line from card to MK.
In fact, few people connect the card directly to the MK; it is much more convenient to connect a card connector to the MK or buy a shield with a connector and all the necessary wiring.
We've sorted out the connection, let's now look at how to use the library Petit FatFs, which is designed for 8-bit microcontrollers with small memory sizes.
The library consists of 5 files:
integer.h- a header file that describes the main data types.
diskio.h- a header file in which prototypes of low-level functions for working with disk and the status codes that they return are declared.
diskio.c- low-level functions must be implemented in this file; initially there are “stubs” there.
pffсonf.h- configuration file.
pff.h- a header file in which prototypes of functions for interacting with the disk file system are declared.
pff.c- the file contains implementations of functions for interacting with the disk file system.
It can be seen that in order for the library to work, it is necessary to implement low-level functions. But if we are talking about AVR or PIC, for them on the website you can download an example of working with the library, which contains the file mmc, it already implements low-level functions. You also need to configure the library in the pff.h file and write the functions necessary for SPI operation.
Functions of Petit FatFs.
FRESULT pf_mount (FATFS*)- the function mounts/unmounts the disk. This function must be called before working with the disk; if you call the function with a null pointer, the disk is dismounted. The function can be called at any time.
Options
FATFS* fs- a pointer to an object of type FATFS; a description of this structure can be found in the file pff.h. We just need to declare a variable of this type.
Return values:
FR_OK (0)
FR_NOT_READY- the device cannot be initialized
FR_DISK_ERR- an error occurred while reading from disk
FR_NO_FILESYSTEM- the disk does not have a valid FAT partition
FATFS fs;//declare an object of type FATFS //mount the disk if (pf_mount(&fs) == FR_OK) ( //the disk is mounted, we work with it //unmount the disk pf_mount(NULL); ) else ( //failed to mount the disk )
FRESULT pf_open (const char* path)- the function opens an existing file. Once the file is opened, you can work with it, that is, read from it and write to it. You can work with an open file until another file is open. The function can be called at any time.
Options
const char* path- pointer to a string indicating the path to the file. The path must be specified completely relative to the root directory, separating the directories with a slash.
Return values:
FR_OK (0)- returned if the function is successful
FR_NO_FILE- file not found
FR_DISK_ERR- disk error
FR_NOT_ENABLED- the disk was not mounted
FATFS fs;//declare an object of type FATFS //mount the disk if (pf_mount(&fs) == FR_OK) ( //open the file located in the root directory if(pf_open("hello.txt") == FR_OK) ( //do something ) //open a file located in the folder new if(pf_open("new/hello.txt") == FR_OK) ( //do something ) //dismount the disk pf_mount(NULL); ) else ( // Failed to mount disk)
FRESULT pf_read(void* buff, WORD btr, WORD* br)- the function reads the specified number of bytes from the file and stores them in a buffer. If the number of bytes read is less than indicated, then the end of the file has been reached.
#define _USE_READ 1
Options:
void* buff- pointer to the buffer in which the read data is stored
WORD btr- number of bytes to be read
WORD*br- pointer to a variable that stores the number of bytes read.
Return values:
FR_OK (0)- returned if the function is successful
FR_DISK_ERR- disk error
FR_NOT_OPENED- the file was not opened
FR_NOT_ENABLED- the disk was not mounted
FATFS fs;//declare an object of type FATFS BYTE buff;//buffer for reading the file WORD br; //counter of bytes read //mount the disk if (pf_mount(&fs) == FR_OK) ( //open the file located in the root directory if(pf_open("hello.txt") == FR_OK) ( //read 10 bytes from it pf_read(buff, 10, &br); if(br != 10) ( //if br is not equal to 10 //it means we have reached the end of the file) ) )
FRESULT pf_write(const void* buff, WORD btw, WORD* bw)- the function allows you to write data to an open file. In order for the function to work, you need to write in the pffconf.h file
#define_USE_WRITE 1
Options:
void* buff- pointer to the buffer we want to write, a zero value finalizes the recording
WORD btw- the number of bytes we want to write
WORD* bw- a pointer to a variable storing the number of bytes that were able to be written. By analyzing this variable, you can find out whether the end of the file has been reached.
Return values:
FR_OK (0)- returned if the function is successful
FR_DISK_ERR- disk error
FR_NOT_OPENED- the file was not opened
FR_NOT_ENABLED- the disk was not mounted
Due to the fact that the library is designed for microcontrollers with small amounts of memory, this function has a number of limitations:
- You cannot create new files, and you can only write to existing ones
- you can't increase the file size
- can't update timestamp
- The write operation can only be started/stopped at the sector boundary
- read-only file attribute cannot prevent writing
In order to understand the penultimate point, you need to know that the card’s memory is divided into blocks (sectors) of 512 bytes each and recording can only be started from the beginning of the sector. Thus, if we want to write 1000 bytes, then the first sector will be written completely, and only 488 bytes will be written to the second, and the remaining 24 bytes will be filled with zeros.
To write to an open file, you must perform the following steps:
- set the pointer to the sector boundary; if set not to the boundary, the pointer will be rounded to the lower sector boundary
- call the write function the required number of times
- finalize the record by calling the function with a null pointer
In order to give an example of how the recording function works, it is necessary to consider one more function.
FRESULT pf_lseek(DWORD offset)- sets the read/write pointer in the open file. You can set the pointer by absolute or relative offset; for absolute offset you need to pass a number to the function
pf_lseek(5000);
for relative, pass the value of the pointer to the current position fs.fptr and the amount of displacement
pf_lseek(fs.fptr + 3000);
In order for the function to work, you need to write in the pffconf.h file
#define_USE_LSEEK 1
Options:
DWORD offset- the number of bytes by which the pointer needs to be shifted.
Return values:
FR_OK (0)- returned if the function is successful
FR_DISK_ERR- disk error
FR_NOT_OPENED- the file was not opened
You can write data to a file as follows.
FATFS fs;//declare an object of type FATFS BYTE buff;//buffer for reading the file WORD br; //counter of bytes read //mount the disk if (pf_mount(&fs) == FR_OK) ( //open the file located in the root directory if(pf_open("hello.txt") == FR_OK) ( //set the pointer to the first sector pf_lseek(0); //write pf_write(buff, 10, &br); //finalize the record pf_write(0, 0, &br); ) )
I’m also leaving here a piece of actually working code that uses all the functions described above.
#define F_CPU 8000000UL #define buff_size 10 #include
FRESULT pf_opendir(DIR* dp, const char * path)- the function opens an existing directory and creates a pointer to an object of type DIR, which will be used to obtain a list of files in the open directory.
In order for the function to work, you need to write in the pffconf.h file
#define_USE_DIR 1
Options:
DIR *dp- pointer to a variable of type DIR.
const char * path- pointer to a string that contains the path to the directory, directories are separated by a slash
Return values:
FR_OK (0)- returned if the function is successful
FR_NO_PATH- could not find the path
FR_NOT_READY- failed to initialize disk
FR_DISK_ERR- disk error
FR_NOT_ENABLED- the disk was not mounted
//declare variables FATFS fs; DIR dir; //mount the disk pf_mount(&fs); //open the directory pf_opendir(&dir, "MY_FOLDER");
FRESULT pf_readdir(DIR* dp, FILINFO* fno)- function allows you to read the contents of a directory. To do this, you need to open the directory using the pf_opendir() function and call pf_readdir(). Each time the function is called, it will return the name of the object (folder/file) located in the specified directory. When it iterates through all objects, it will return a null string in the fno.fname array element.
In order for the function to work, you need to write in the pffconf.h file
#define_USE_DIR 1
Options:
DIR *dp- pointer to a variable of type DIR, which must be previously declared
FILINFO *fno- a pointer to a variable of type FILINFO, which must be previously declared.
Return values:
FR_OK- successful completion of the function
FR_DISK_ERR- disk error
FR_NOT_OPENED- directory is not open
FATFS fs; FRESULT res; FILINFO fno; DIR dir; //mount the disk pf_mount(&fs); //open the directory res = pf_opendir(&dir, MY_FOLDER); //read the contents of the directory for(;;)( res = pf_readdir(&dir, &fno); //check if there were any errors while reading //and if there are any other files in the specified directory if ((res != FR_OK) || ( fno.fname == 0))( break; ) //output in a convenient way fno.fname usart_sendStr(fno.name); usart_sendStr(/r); )
And finally, I’ll leave the working draft here
