MicroSD Card Error

I’ve got a P1S with a high quality SanDisk 256gb card formatted to Fat32 in it and have the camera record option turned off. It’s been working fine since I started using the card almost 2 months ago.

Lately when sending something to print I’ll get this “MicroSD Card Error” message along with a code that I’ll have to come back and add once a print is done. But if I go to the printer it shows the card and let’s me view the files and I can put it in my computer and it works fine and doesn’t find any issues with it.

What I have found is that if I eject the card from the printer and stick it right back in, a file will send and print fine. They last time I did this I noticed when I put the card back in, it said there was 0.1 gb less used space which I would think that wouldn’t change from just ejecting and putting back in?

I did download the portable version of Orca Slicer a few days ago and it might be happening more often with it than Bambu Studio but happens to both. It was also happening before I downloaded it and since it’s not “installed” on my computer and did not change any registry values, I can’t imagine the use of the program is causing it.

I’ve tried searching and it seems like there are lots of issues with the SD card but the main solution is to replace the cheap card it comes with which doesn’t apply. Other than that, I didn’t see many solutions and didn’t see this particular problem very much.

Since my printer is in a shop on another part of the property, it’s a pain to have to get up and go out there to mess with the card. Also, I’ve tried multiple high quality cards and the Internet/LAN connection is strong, fast, and not an issue.

Any suggestions on things to try?

So the 32GB capacity restriction in FAT32 didn’t cause any issues?

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Have you tried another SD card? Have you tried reformatting the SD card in a PC and checked verify?

I ask because SD cards do wear out. If you have been writing to the same sectors over and over again, it’s worth noting that most NAND technology is only good for a 1,000 write cycles. Once a cell is dead, the onboard logic is supposed to re-locate that sector to another spot through wear leveling. But it doesn’t always work perfectly. I’ve had experiences where a card would seem to work OK but then get funky errors. When I put it through diagnostics, I would then find out that it had issues. Reformatting would help but if it’s a heavily traveled sector. It may not work as advertised all the time.

SanDisk is my go to memory card maker of choice when it comes to reliability. Look for their model that is geared towards use in surveillance cameras. I’ve used those for my Dash Cam and my house camera. Whereas the standard SD memories would start to fail in those applications, the extended memory versions worked better.

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I think the 32 gb is more a Windows restriction on what size limit it will format as Fat 32. In order to format larger memory, an application has to be downloaded to do so. Beyond that, 128 and 256 gb cards have worked fine until now.

I do have multiple cards I’ve tried and it doesn’t seem to make a difference which card is loaded. And with the saving video turned off I don’t think the card is being rewritten to and it’s basically just saving each new file that’s being sent to print.

I’ve put the cards in my computer which has no problems accessing and reading/writing to it and I’ve tried checking for errors and it doesn’t find anything wrong with it. I might try downloading a more sophisticated program for analyzing memory but I don’t think that’s the issue at this point. The fact I can eject the card and then pull it and reinsert it, and it then sends and prints fine seems more to do with the printer and maybe something to do with RAM or cache. I just formatted a brand new 128 gb card that I’m going to try using for a while and see what happens.

You can download an SD Card formatter from the SD Card Memory organization here:

SD cards don’t have a lot of “smarts” to deal with error conditions, not like a HDD or SSD does (even though the Flash chips in a SD card are similar to the ones in a SSD, the SSD has its own controller that layers on a lot of sophistication both for higher performance and increased data integrity). The contents of a SD card can become corrupted, or regions can fail in ways that the built-in controller on the chip can’t handle, or the device accessing the SD card can’t handle.

I would reformat the card. Do the long format, not the quick format.

most NAND technology is only good for a 1,000 write cycles

Not strictly correct. It is heavily dependent on the class of card. Samsung recently started selling cards for video surveillance use-cases that are rated to 10K cycles. These cards are also much faster at writing data. But it’s safe to say that the less expensive the NAND, the fewer write/erase cycles it will deliver before it wears out. (if you want to spend a lot of money, NAND used in the “SLC” mode can be good for as much as 100K cycles).

But because SD cards don’t do “refresh” operations (an SSD is constantly scanning your data to make sure it’s in tip-top condition), SD cards can start to cough up errors long before they wear out. And the propensity to have errors as a function of how long data has been “at rest” on the card increases with both wear level and storage temperature.

1000 cycles might not sound like a lot, but on a 32GB card that’s 32 Terabytes of data. There are very fast SD cards on the market, but even the high end cards can only muster around 100MB/S sustained writing (excluding SD Express, which hooks directly in to the NVMe bus and can go a lot faster. Our printers don’t support this interface). So at 100MB/S, that’d take 89 hours of continuous writing to get there.

I’d be surprised if you’ve worn out the card. It’s possible that it’s developed a defect, no manufacturing process yields 100% perfect parts. It’s also possible that the card is a counterfeit. Samsung and SanDisk both have problems with this. They look like legitimate product but they’re made with “scavenged NAND” (like, have you wondered what happens to the cell phone you recycle? Parts like the NAND get stripped and sold for pennies on the dollar. Less reputable manufacturers will buy these cards and package them as if they were new product).

It’s not like a 32GB card costs much nowadays. If reformatting doesn’t fix your current card, buy a new card and throw this one away (or use it on something you don’t care that much about, if you can’t always get all the data back that was written to it).

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I reecently started getting this error right aftere the latest P1P firmware upgrade. Not sure why is happening. I cannot print anything at all. It constantly throws this error. Any suggestions to fix it would be helpful.

“MicroSD card read/write exception”

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The error is self explanatory. There is an issue with your SD card. Don’t read too much into the fact that it happened during your upgrade, that may simply be coincidence.

Cause

It may help to understand that Bambu’s design uses the SD card as a cache. SD cards don’t like frequent writes. The blocks on the card typically have a maximum lifespan of less than 10,000 writes. The one’s that shipped with the printer were the cheapest Bambu could source, I replaced mine within the first six months.

Simple first remedy

But before replacing the SD card with a more robust one, you might try simply reformatting the card from the printer menu. This quick troubleshooting test will do two things: first, any bad blocks will be moved to a bad block table and taken out of the equation; second, it will create a clean slate. If the capacity after formatting reduces, that’s a strong indicator that the card had many errors. Either way, it’s a simple, quick troubleshooting step. If the problem goes away for a time and then starts to reappear, you’ll know it’s likely a suspect SD card.

Long term remedy

If the SD card is in fact identified as the culprit, one option is to replace it with a high-endurance SD card, which is typically designed for applications like surveillance cameras that do many writes. Just search for “SD card high endurance,” and you’ll find many options. High endurance cards are advertised to allow over 1,000,000 writes which is why they are often found in Dashcams and surveillance cameras that are constantly over writing the same blocks.

High Endurance SD cards 32MB limit

Here’s a search term on Amazon that will give you some suggestions. Note: Bambu does not support anything beyond 32GB. Amazon.com : high endurance SD card 32gb

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I’m having the same issue. I’ve tried three different cards, including the original. They all are recognized on other devices and formatted FAT32. The issue started after my last firmware update.

Does the printer require that an SD card be installed or will it work fine without a card?

The P series printer needs an SD card installed. The X series does not.

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