I'm getting really tired of "SD Card Timeout" print failures under f/w 0.0.8 using one of my original Zortrax cards. I've cleaned the contacts and recently did a full (not "quick") format but still get failures. It's nice that the f/w now reports the cause of the print stop, but why the failures now occur much more often is a bit of a mystery. Whatever.
Anyone have a recommendation for a card size/brand that always works? I know about the size limit for updates but I can always keep the original cards around for that.
Not sure but the original Zortrax card has to be one of the slowest accessing cards ever. I notice this when it is plugged into the Mac downloading files.
As you may be aware, flash cards are block sectored devices almost like a disk drive, as they age access times can increase due to several factors (error correction, block sparing, 'read many' errors, etc.). I have noticed this increase on the Zortrax card, originally it was much faster. Class 10 cards are pretty cheap these days and the access times on them are several orders of magnitude faster than the supplied Zortrax card. I like Sandisk or Lexar - you can be pretty sure they aren't using the 'floor sweeping' devices that some of the non name brand cheapies are using.
I was still having trouble with a fresh 8GB Sandisk card, then Catalin C advised me that if a timeout error occurs on a card, copying the file in question to another card may propagate the error somehow. Seems farfetched, but re-slicing, saving to the desktop, then copying to the new SD card finally produced a successful print.
I was still having trouble with a fresh 8GB Sandisk card, then Catalin C advised me that if a timeout error occurs on a card, copying the file in question to another card may propagate the error somehow. Seems farfetched, but re-slicing, saving to the desktop, then copying to the new SD card finally produced a successful print.
Maybe someone can provide a technical explanation for that - I can't - just trial and error.
I've switched to MicroSD + SD adaptor for some time. Adaptors are cheap and MSD can be used on pretty much any other devices - cameras, phones (except the damned Iphones, of course).
My old knowledge from FPGA time says: when technology going into smaller um to get faster speed and smaller voltage then IC is more prone to communication errors I using standard card delivered with Zortrax and I think slower and more old technology should works better in such of electromagnetic noisy enviorement the best is to choose cheapest and oldest card type.
I was still having trouble with a fresh 8GB Sandisk card, then Catalin C advised me that if a timeout error occurs on a card, copying the file in question to another card may propagate the error somehow. Seems farfetched, but re-slicing, saving to the desktop, then copying to the new SD card finally produced a successful print.
Compare the file size on desktop to bad one on card. Just had this happen again.. I saved directly to card. 1652kb Failed!!!! Saved to desktop 2032kb.. Transferred to card and verified file size. Success!! You would think it would detect an error right off. Maybe it needs to check for a return to X-Y zero at end of code so it knows it's complete.. Good idea???? :huh: :D
Compare the file size on desktop to bad one on card. Just had this happen again.. I saved directly to card. 1652kb Failed!!!! Saved to desktop 2032kb.. Transferred to card and verified file size. Success!! You would think it would detect an error right off. Maybe it needs to check for a return to X-Y zero at end of code so it knows it's complete.. Good idea???? :huh: :D
Hi,
Good idea I think, the printer could indeed check if the file is complete & correct. A simple MD5 saved at the same time the zcode is but in a different file could do the trick. Z Suite could also provide a “verify” option based in the same system. Drawback is the need to slide again all models again…
I consider SD-Cards a non reliable storage medium. I’m not alone with this, almost every micro computer forum tells that if the system should do daily business one should put it on a different media, best of all a harddisk or ssd.
The problem with SD is not caused by minimizing components (micro SD is not less reliable) but because of a combination of several factors. The hardware itsself (thin plastic housing and weak contacts asking for mechanical and EMI trouble), the controller (same issues for the cheaper ones) and drivers/file system in the OS.
Most of us may have heard about failing media in cameras, but the usage with the M200 is much more demanding.
In a camera the card is written once a picture is taken and the pics are often taken from the camera via USB with the card staying in the camera.
With the M200 the card is taken off for every change of print files and the card is in use all the time while printing.
Zortrax has reason to suggest not to save a file directly to SD from Z-Suite and of course copying between SDs calls for trouble one more time. I always avoid this and had not a single failed print because of the card with my original Z-SD. Just the mechanical write protect lock is weak now causing trouble when inserting the card at the Mac.
It would not be impossible to have read errors from a flash card. To minimize geometries (and maximize profits) the cells in NAND flash are made as small as possible, to the point where a certain error rate is expected. This is dealt with by error correction applied to the block on reads. They are block sectored devices - not random access - and so have a catalog indexing which blocks are strung together to make which files. Blocks are bad even when new, these are spared out in the manufacturing process. Blocks can go bad in use, these are supposed to be spared out by the OS using them. If the catalog gets corrupted, then you are somewhat screwed. In addition to those problems, NAND flash has a unique "read many" error mode in addition to the "write many" errors that most programmable non-vols have. Most forms of memory can be read an indefinite number of times, but in flash this may eventually cause the cell to flip. The read many and write many errors again should be dealt with by what is called "wear leveling" algorithms in the OS, basically moving stuff around so that the same locations are not used time after time and data is rewritten before it is read too much.
At least that was all the case last time I was involved in them. Miracle devices really, but not without their issues.
Actually I'm pretty sure I have a malfunctioning card socket. Using an almost-new Sandisk 8GB card, I select "Models" and it says "no files found". Then I push the top of the card toward the back of the printer, select "models" again, and all the files are there.
I'm having this problem only when I transfer zcode to the sd through a usb hub. When I'm pluging the sd card to a rear main usb socket everything is fine.
Actually I'm pretty sure I have a malfunctioning card socket. Using an almost-new Sandisk 8GB card, I select "Models" and it says "no files found". Then I push the top of the card toward the back of the printer, select "models" again, and all the files are there.
I seem to be having the same problem on my HP desktop, which I use for ZSuite and transferring photos from a digicam SD card. It can be difficult for Win 7 to recognize either the Zortrax or digicam SD cards unless the cards are nudged in the card reader and I sometimes have the same problem in the Zortrax card reader. Replacing the HP reader will probably be a lot easier than replacing the Zortrax reader. Is the Zortrax reader user-replaceable?
Nifty use of scrap raft. Is that a surface mount (term?) solder job on the reader? How do you desolder all the pins on the old reader at one time? Snip off the terminals and desolder the little stubs one at a time?
If you elect to replace your reader, please post some details about the technique and part source.
Yes, it's surface-mount (SMD). Removing an SMD part that's going to be scrapped is usually pretty easy - as you say, you can snip leads and de-solder them individually. In the case of this card socket, however, there's not really much to snip, and you want to be careful not to rip up any PCB tracks. A hot air rework tool would probably be best, although the solder-flood method often works well too - melt a load of solder onto all the pins at once, remove the part, then remove the solder with wick.
