First attempt at printing gives "Production complete" message after 6.5 seconds

Hello. I am working on the "Software Tweaking" page of the Darwin build instructions [www.reprap.org]. Specifically, I am in the "Measure the deposited filament section" area of the page, which instructs me to, for the first time with this machine, print a .stl file, widebar.stl.

After setting the parameters as specified (Except that I used 210C for a extrusion temp, as I am using HDPE), closing the program, opening it, loading the widebar.stl file, selecting "HDPE", and clicking "Start build", my RepRap is motionless. About 7 seconds later, I get the following message:



Apparently, the reprap-host software thinks it finished the whole job in 6.5 seconds. Wouldn't that be nice?

Any ideas about what the problem is?

Some facts, as I understand them:

1.) I am using the latest released reprap-host software, reprap-host-20080523.zip

2.) I am using the reprap single-Arduino SNAP file from reprap-arduino-firmware-1.3.zip

3.) The stepper motor exerciser works when I start up the reprap-host program fresh, and I am able to control each stepper.

4.) The extruder exerciser works when I start up the reprap-host program fresh, and I am able to heat, sense temperature, and extrude.

5.) On a typical run of reprap-host, doing things like 3 and 4, I usually get the following console messages:

$ reprap-host
Experimental: JNI_OnLoad called.
Stable Library
=========================================
Native lib Version = RXTX-2.1-7
Java lib Version = RXTX-2.1-7
Exception in thread "RepRap" java.lang.NullPointerException
at javax.swing.ImageIcon.(ImageIcon.java:138)
at org.reprap.gui.botConsole.PrintTabPanel.initComponents(Unknown Source)
at org.reprap.gui.botConsole.PrintTabPanel.(Unknown Source)
at org.reprap.gui.botConsole.BotConsoleFrame.initComponents(Unknown Source)
at org.reprap.gui.botConsole.BotConsoleFrame.(Unknown Source)
at org.reprap.gui.botConsole.BotConsoleFrame$1.run(Unknown Source)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)
sendMessage error - retrying
sendMessage error - retrying
sendMessage error - retrying
sendMessage error - retrying
sendMessage error - retrying


Everything before the sendMessage errors happens on startup, and the sendMesage errors happen usually when I'm doing something like telling it to extrude or run a motor. These errors are unpredictable. On a given program run, I may get 0 or I may get 10. Usually, they come one at a time.

Are these sendMessage errors normal? The retries seem to work fine, and the cumulative effect seems to just be a delay in the robot's response.

6. Sometimes when I try to print the stl file, I get only the errors mentioned above. Other times, I've gotten a slew of the following errors:

java.lang.NullPointerException
at org.reprap.comms.snap.SNAPCommunicator.receivePacket(Unknown Source)
at org.reprap.comms.snap.SNAPCommunicator.sendMessage(Unknown Source)
at org.reprap.comms.IncomingMessage.(Unknown Source)
at org.reprap.devices.GenericExtruder$RequestIsEmptyResponse.(Unknown Source)
at org.reprap.devices.GenericExtruder.RefreshEmptySensor(Unknown Source)
at org.reprap.devices.GenericExtruder.TEMPpollcheck(Unknown Source)
at org.reprap.devices.GenericExtruder.getTemperature(Unknown Source)
at org.reprap.gui.botConsole.GenericExtruderTabPanel.refreshTemperature(Unknown Source)
at org.reprap.gui.botConsole.GenericExtruderTabPanel.access$100(Unknown Source)
at org.reprap.gui.botConsole.GenericExtruderTabPanel$1.run(Unknown Source)
java.lang.NullPointerException
at org.reprap.comms.snap.SNAPCommunicator.receivePacket(Unknown Source)
at org.reprap.comms.snap.SNAPCommunicator.sendMessage(Unknown Source)
at org.reprap.comms.IncomingMessage.(Unknown Source)
at org.reprap.devices.GenericExtruder$RequestIsEmptyResponse.(Unknown Source)
at org.reprap.devices.GenericExtruder.RefreshEmptySensor(Unknown Source)
at org.reprap.devices.GenericExtruder.TEMPpollcheck(Unknown Source)
at org.reprap.devices.GenericExtruder.getTemperature(Unknown Source)
at org.reprap.gui.botConsole.GenericExtruderTabPanel.refreshTemperature(Unknown Source)
at org.reprap.gui.botConsole.GenericExtruderTabPanel.access$100(Unknown Source)
at org.reprap.gui.botConsole.GenericExtruderTabPanel$1.run(Unknown Source)

7. I have tried shutting down the RepRap, resetting the Arduino, turning the RepRap back on, and starting reprap-host again. Same 6-second print.

Any thoughts? Has this happened to anyone else? Thanks for your help.

Wow... It seems like someone else, just a little while ago, had the same problem as I did. [forums.reprap.org]

Changing nullcartesian to cartesian in my preferences fixed the problem. What is nullcartesian for, anyway, and why is it the default?

Also, if anyone has any insight into the errors I get, I would greatly appreciate hearing it.

~Andy

Some other errors I've gotten:

When setting the Extruder0_XYSpeed to 255, and trying to print the above stl, the machine starts printing, then stops, and eventually outputs:

IO error/timeout, resending

Printing at the 247 speed works fine.

Another error I've gotten:

Exception in thread "Producer" java.lang.StackOverflowError
at org.reprap.geometry.polygons.treeList.getChild(Unknown Source)
at org.reprap.geometry.polygons.treeList.setParents(Unknown Source)
at org.reprap.geometry.polygons.treeList.setParents(Unknown Source)
at org.reprap.geometry.polygons.treeList.setParents(Unknown Source)
at org.reprap.geometry.polygons.treeList.setParents(Unknown Source)
at org.reprap.geometry.polygons.treeList.setParents(Unknown Source)
at org.reprap.geometry.polygons.treeList.setParents(Unknown Source)


Just thought I should post them as a sort of bug report.

Quote

Changing nullcartesian to cartesian in my preferences fixed the problem. What is nullcartesian for, anyway, and why is it the default?

It just does a build preview, and no actual IO. It means the software can run and be tested without needing a real cartesian bot attached to it.