Cannot initialise SD card 0: Card is unusable

  • I am having an issue with my new Duet Wifi Board (Firmware 1.19 Board Version 1.0). I installed it fine and have been using it for about a week now. Tonight I went to upload a new gcode file and it stated that it loaded all of it but the file size showed 0. Thinking it was a problem with my slicer I redid the file and tried to upload it again. I received an error message about being unable to access the sd card - I don't remember what the message was but I have gotten similar a couple of times and was able to power off, remove and replace the sd card and power back on so I figured that was all I needed to do. When I repowered the printer it would not connect to the the wifi. I attached a usb cable and tried to reinitialize the wifi and realized it was not reading the sd card.

    I removed the card and plugged it into my computer and it works fine.
    I formatted a spare card I had and copied the files to it but the Duet will not recognize either card.
    The LEDs for 3.3v, 5v, and 24v power seem to act as they should.
    Connecting to the board via usb is not an issue and I have seemingly successfully reflashed the firmware to the same version it came with Using BOSSA. The Com port numbers and descriptors changed as described here after using erase and reflashing.
    No wiring changes have been made since successfully using the sd card but I did unplug all but the power connections to the board without any change.
    I get the same error message with both sd cards: SENDING:M21 Cannot initialise SD card 0: Card is unusable
    Both cards work fine in both of my Windows PCs and I have run scandisk on both without errors.
    M122 shows that it is recognizing whether an sd card is present or not but it won't seem to do anything with it.

    Is there something else I can try to get the sd card to read?

  • UPDATE: I have continued to tinker with this and have managed to get it to work… Sort of. I noticed that there is a small amount of slop in the way the SD card locks into its slot. The card clicks in as it seems it should but With a small amount of pressure it can be wiggled just a bit. I have no experience with Micro SD cards outside of my cell phone which holds it very firmly in place. I tried putting just enough pressure on the top of the card to hold it against the base of the slot and plugged in the USB cable. I was then able to mount the card using M21 and it reported the correct card size. I could still not read the file list or do anything that required accessing the SD card. I experimented a bit more and found that if I apply that pressure only on the edge closest to the USB connector that I can mount and read the card, it connects to the WIFI on its own and I can bring up the web interface.

    I obviously cannot stand there holding the SD card the whole time it is printing and as soon as I let go it stops reading the card. Can anyone suggest a work around that will make my board reliably useable again without damaging it or the card?

  • administrators

    I'm sorry that have received a Duet with a fault. I suspect that one of the pins as the back of the socket isn't properly soldered to the PCB. I suggest you ask your supplier to replace the Duet.

  • OK. Thanks David, I was really hoping that this was a fixable problem so I didn't have to return it. I have already been in touch with Filastruder and I have no doubt they will take care of me.
    I love the board by the way. I was a bit hesitant to spend that much but I have not been disappointed. Your Wiki and support forum here made wiring and configuring pretty straight forward and I learned a lot. While it was running it did an awesome job and I know I've only scratched the surface of what it can do. I really appreciate all the work you folks put into this.

  • administrators

    My guess is that the problem is a bad joint between one of the pins at the back of the SD card socket and the PCB. But unless you are experienced in SMD PCB assembly and have a fine-tipped soldering iron, don't attempt to repair it yourself because that risks causing further damage.

  • Nope, I am JUST smart enough to know I do not have the proper tools or experience to attempt that kind of repair. I have already set up the return with Filastruder, which is where I purchased this board. I was really impressed to get a response from their customer service folks on a Sunday but everything is good to go. I should be back up and printing with a replacement board in a few days. Thank you.


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