# Why output stops due to "!SD busy" error? **URL:** \ **Category:** General Discussion\ **Created:** [September 6, 2022, 8:12am UTC](https://klipper.discourse.group/t/why-output-stops-due-to-sd-busy-error/4064 "2022-09-06T08:12:14Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Lee](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/lee/32/2728_2.png) [@Lee](https://klipper.discourse.group/u/Lee)\ **Post date:** [September 6, 2022, 8:12am UTC](https://klipper.discourse.group/t/why-output-stops-due-to-sd-busy-error/4064/1 "2022-09-06T08:12:14Z")
### Basic Information: Printer Model: AM8 MCU / Printerboard: SKR1.4, A8 baord, RPI 4 `klippy.log` _Fill out above information and in all cases attach your_ `klippy.log` _file. Pasting your_ `printer.cfg` _is **not** needed_ ### Describe your issue: These days I am writing macros to use “MMU” and testing them to know the optimal state. I am checking it by slicing with XYZ cube calibration. “!!!SD busy” continues to work. Perhaps the cause is the PAUSE command. If there is a problem and you modify the macro, then it will stop in a paused state. maybe in a macro “{% if printer.pause\_resume.is\_paused != true %}” I wonder if it’s not possible to check the real-time change when checking this condition. “printer.query\_endstops.last\_query” Like this object, I wonder if it needs to be updated with QUERY\_ENDSTOPS before to recognize the change. Prusa Slicer Startup gcode Additions include: all\_eject mmu\_unlock home\_mmu\_only M140 S60 ;set bed temp M190 S60 ; wait for designated temp G28 ; home axis G1 Z20 X-10 y0 F1000 M104 S230 ;set extruder temp M109 S230 ; wait for designated temp t0 G21 G90 M82 M107 G92 E0 G1 Z10 F400 G1 X5 Y10 F1200 G1 Z0.3 G1 Y70 E12 F300 G1 Y80 M73 P0 R35 G1 Z10 G92 E0 M117 Printing… G21 ; set units to millimeters G90 ; use absolute coordinates M82; use absolute distances for extrusion G92 E0 added like this I translated it with a translator, so please understand if it’s awkward. I will wait for your reply [klippy (2).log](https://klipper.discourse.group/uploads/short-url/9HH5OwPqlANdiQNQxGrB4R2wly5.log) (390.3 KB) ---
**Author:** ![Sineos](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/sineos/32/18_2.png) [@Sineos](https://klipper.discourse.group/u/Sineos)\ **Post date:** [September 6, 2022, 8:56am UTC](https://klipper.discourse.group/t/why-output-stops-due-to-sd-busy-error/4064/2 "2022-09-06T08:56:17Z")
Your log shows: ```auto Got EOF when reading from device Got EOF when reading from device Timeout with MCU 'mcu' (eventtime=88155.908377) Transition to shutdown state: Lost communication with MCU 'mcu' Dumping gcode input 0 blocks ``` `Got EOF when reading from device` is and indication that the Linux operating system has lost contact to an USB device (in this case the `mcu`). This leads some moments later to `Timeout with MCU 'mcu' (eventtime=88155.908377)`. This points to some hardware issue: - Cable - Connectors - Ports - General failure of a hardware component Check with `sudo dmesg` if there are any USB related error messages ---
**Author:** ![Lee](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/lee/32/2728_2.png) [@Lee](https://klipper.discourse.group/u/Lee)\ **Post date:** [September 7, 2022, 3:28pm UTC](https://klipper.discourse.group/t/why-output-stops-due-to-sd-busy-error/4064/3 "2022-09-07T15:28:42Z")
I checked with sudo dmesg and there is a log like this. Among them ch341-uart ttyUSB0: usb\_serial\_generic\_write\_bulk\_callback - urb stopped: -32 There seems to be an error, is this a problem? [195.241302] usb 1-1.4: USB disconnect, device number 4 [196.043001] usb 1-1.4: new full-speed USB device number 5 using xhci\_hcd [196.182811] usb 1-1.4: New USB device found, idVendor=1d50, idProduct=614e, bcdDevice= 1.00 [196.182844] usb 1-1.4: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [196.182860] usb 1-1.4: Product: lpc1768 [196.182875] usb 1-1.4: Manufacturer: Klipper [196.182890] usb 1-1.4: SerialNumber: 0C600014618445AF60C2D65CC22000F5 [196.189684] cdc\_acm 1-1.4:1.0: ttyACM0: USB ACM device [636.396526] usb 1-1.4: USB disconnect, device number 5 [636.692540] ch341-uart ttyUSB0: usb\_serial\_generic\_read\_bulk\_callback - urb stopped: -32 [636.692982] ch341-uart ttyUSB0: usb\_serial\_generic\_read\_bulk\_callback - urb stopped: -32 [636.780181] ch341-uart ttyUSB0: usb\_serial\_generic\_write\_bulk\_callback - urb stopped: -32 [636.806387] ch341-uart ttyUSB0: usb\_serial\_generic\_write\_bulk\_callback - urb stopped: -32 [636.858487] ch341-uart ttyUSB0: usb\_serial\_generic\_write\_bulk\_callback - urb stopped: -32 [636.908513] usb 1-1.1: USB disconnect, device number 3 [636.910696] ch341-uart ttyUSB0: ch341-uart converter now disconnected from ttyUSB0 [636.910787] ch341 1-1.1:1.0: device disconnected [642.287671] usb 1-1.1: new full-speed USB device number 6 using xhci\_hcd [642.424106] usb 1-1.1: New USB device found, idVendor=1a86, idProduct=7523, bcdDevice= 2.60 [642.424126] usb 1-1.1: New USB device strings: Mfr=0, Product=2, SerialNumber=0 [642.424141] usb 1-1.1: Product: USB2.0-Serial [642.429000] ch341 1-1.1:1.0: ch341-uart converter detected [642.434361] usb 1-1.1: ch341-uart converter now attached to ttyUSB1 [644.017725] usb 1-1.4: new full-speed USB device number 7 using xhci\_hcd [644.157495] usb 1-1.4: New USB device found, idVendor=1d50, idProduct=614e, bcdDevice= 1.00 [644.157514] usb 1-1.4: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [644.157530] usb 1-1.4: Product: lpc1768 [644.157545] usb 1-1.4: Manufacturer: Klipper [644.157560] usb 1-1.4: SerialNumber: 0C600014618445AF60C2D65CC22000F5 [644.162364] cdc\_acm 1-1.4:1.0: ttyACM1: USB ACM device [1251.306261] usb 1-1.4: USB disconnect, device number 7 [1252.074247] usb 1-1.1: USB disconnect, device number 6 [1252.075069] ch341-uart ttyUSB1: ch341-uart converter now disconnected from ttyUSB1 [1252.075196] ch341 1-1.1:1.0: device disconnected [91717.465706] usb 1-1.1: new full-speed USB device number 8 using xhci\_hcd [91717.622022] usb 1-1.1: New USB device found, idVendor=1a86, idProduct=7523, bcdDevice= 2.60 [91717.622041] usb 1-1.1: New USB device strings: Mfr=0, Product=2, SerialNumber=0 [91717.622057] usb 1-1.1: Product: USB2.0-Serial [91717.631305] ch341 1-1.1:1.0: ch341-uart converter detected [91717.637863] usb 1-1.1: ch341-uart converter now attached to ttyUSB0 [91718.185671] usb 1-1.4: new full-speed USB device number 9 using xhci\_hcd [91718.325344] usb 1-1.4: New USB device found, idVendor=1d50, idProduct=614e, bcdDevice= 1.00 [91718.325353] usb 1-1.4: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [91718.325359] usb 1-1.4: Product: lpc1768 [91718.325365] usb 1-1.4: Manufacturer: Klipper [91718.325371] usb 1-1.4: SerialNumber: 0C600014618445AF60C2D65CC22000F5 [91718.332027] cdc\_acm 1-1.4:1.0: ttyACM0: USB ACM device ---
**Author:** ![Sineos](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/sineos/32/18_2.png) [@Sineos](https://klipper.discourse.group/u/Sineos)\ **Post date:** [September 8, 2022, 7:38am UTC](https://klipper.discourse.group/t/why-output-stops-due-to-sd-busy-error/4064/4 "2022-09-08T07:38:28Z")
> [@Lee](#): > > [636.692540] ch341-uart ttyUSB0: usb\_serial\_generic\_read\_bulk\_callback - urb stopped: -32 This is definitively a problem. - Try without webcam. Webcam is putting high strain on the USB - Alternatively wire the MCU with direct serial connection to the RPi ---
**Author:** ![Lee](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/lee/32/2728_2.png) [@Lee](https://klipper.discourse.group/u/Lee)\ **Post date:** [September 9, 2022, 1:34am UTC](https://klipper.discourse.group/t/why-output-stops-due-to-sd-busy-error/4064/5 "2022-09-09T01:34:01Z")
There are skr1.4 board and A8 board for MMU2 that use usb The camera is currently using the CSI port as a Raspberry Pi cam. Is this a problem, too? I think the CH341 driver is probably A8 board, but I will buy the cable and change it. Thank you for your answer. I will post a review after changing the cable. ---
**Author:** ![Sineos](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/sineos/32/18_2.png) [@Sineos](https://klipper.discourse.group/u/Sineos)\ **Post date:** [September 9, 2022, 9:49am UTC](https://klipper.discourse.group/t/why-output-stops-due-to-sd-busy-error/4064/6 "2022-09-09T09:49:11Z")
The CH3xx serial to USB chips are known for being problematic and some recent Kernel variants contain buggy drivers. > [@Lee](#): > > The camera is currently using the CSI port as a Raspberry Pi cam. Is this a problem, too? Not sure. The RPi being a highly integrated device so many resources are shared. How far they influence each other I cannot tell. Worth a try.