Cura 3.1 doesn't see my printer on USB

[Smokingman 0]

When Using Cura 15.04.6, I can print just fine with USB on my Prusa i3. However, I wan't to use some of the new features in 3.1, but it doesn't see my printer.

I looks like it finds it in the logs, but then tries different baud rates and fails. Is there a way to manually set the connection information, or get the auto detection working?

Here's what I think are the relevant portions of the log:

 

2017-12-09 17:29:20,000 - DEBUG - USBPrinting.USBPrinterOutputDevice._connect [312]: Attempting to connect to COM3...2017-12-09 17:29:20,029 - WARNING - UM.OutputDevice.OutputDeviceManager.removeOutputDevice [126]: Could not find output device with id COM3 to remove...2017-12-09 17:29:20,775 - DEBUG - USBPrinting.USBPrinterOutputDevice._connect [328]: Attempting to connect to printer with serial COM3 on baud rate 1152002017-12-09 17:29:24,429 - DEBUG - USBPrinting.USBPrinterOutputDevice._connect [354]: Correct response for auto-baudrate detection received.2017-12-09 17:29:24,620 - DEBUG - USBPrinting.USBPrinterOutputDevice._connect [354]: Correct response for auto-baudrate detection received.2017-12-09 17:29:25,633 - INFO - FirmwareUpdateChecker.FirmwareUpdateChecker._onContainerAdded [52]: You have a 'Prusa i3' in printer list. Let's check the firmware!2017-12-09 17:29:25,636 - INFO - cura.Settings.GlobalStack.addExtruder [74]: Extruder[Prusa i3 fdmextruder] added to [Prusa i3] at position [0]2017-12-09 17:29:25,637 - WARNING - UM.Settings.ContainerStack.addMetaDataEntry [162]: Meta data with key machine was already added.2017-12-09 17:29:25,639 - DEBUG - UM.Settings.ContainerRegistry.load [231]: Loading data into container registry took 5.451940536499023 seconds2017-12-09 17:29:25,929 - DEBUG - UM.Controller.setActiveView [86]: Setting active view to SolidView2017-12-09 17:29:25,936 - WARNING - cura.Settings.GlobalStack.addExtruder [70]: Extruder [Prusa i3 fdmextruder] has already been added to this stack [Prusa i3]2017-12-09 17:29:25,937 - WARNING - UM.Settings.ContainerStack.addMetaDataEntry [162]: Meta data with key machine was already added.2017-12-09 17:29:25,938 - WARNING - cura.Settings.ExtruderManager.registerExtruder [220]: Extruder [Prusa i3 fdmextruder] has already been registered on machine [Prusa i3], not doing anything...2017-12-09 17:29:27,470 - WARNING - cura.Settings.GlobalStack.addExtruder [70]: Extruder [Prusa i3 fdmextruder] has already been added to this stack [Prusa i3]2017-12-09 17:29:27,472 - WARNING - UM.Settings.ContainerStack.addMetaDataEntry [162]: Meta data with key machine was already added.2017-12-09 17:29:27,473 - WARNING - cura.Settings.ExtruderManager.registerExtruder [220]: Extruder [Prusa i3 fdmextruder] has already been registered on machine [Prusa i3], not doing anything2017-12-09 17:29:27,546 - DEBUG - USBPrinting.USBPrinterOutputDevice._connect [328]: Attempting to connect to printer with serial COM3 on baud rate 250000...2017-12-09 17:29:34,196 - DEBUG - USBPrinting.USBPrinterOutputDevice._connect [328]: Attempting to connect to printer with serial COM3 on baud rate 2304002017-12-09 17:29:39,333 - DEBUG - AutoSave.AutoSave._onTimeout [48]: Autosaving preferences, instances and profiles2017-12-09 17:29:40,708 - DEBUG - USBPrinting.USBPrinterOutputDevice._connect [328]: Attempting to connect to printer with serial COM3 on baud rate 576002017-12-09 17:29:47,215 - DEBUG - USBPrinting.USBPrinterOutputDevice._connect [328]: Attempting to connect to printer with serial COM3 on baud rate 384002017-12-09 17:29:53,725 - DEBUG - USBPrinting.USBPrinterOutputDevice._connect [328]: Attempting to connect to printer with serial COM3 on baud rate 192002017-12-09 17:30:00,236 - DEBUG - USBPrinting.USBPrinterOutputDevice._connect [328]: Attempting to connect to printer with serial COM3 on baud rate 96002017-12-09 17:30:06,746 - ERROR - USBPrinting.USBPrinterOutputDevice._connect [366]: Baud rate detection for COM3 failed2017-12-09 17:30:06,747 - DEBUG - USBPrinting.USBPrinterOutputDevice.close [380]: Closing the USB printer connection.2017-12-09 17:30:06,747 - DEBUG - USBPrinting.USBPrinterOutputDevice.close [385]: PrinterConnection.close: cannot join current thread (expected)2017-12-09 17:30:06,751 - WARNING - UM.OutputDevice.OutputDeviceManager.removeOutputDevice [126]: Could not find output device with id COM3 to remove