Duet loses serial communication when SD card installed

Good morning,

Just yesterday I acquired an Ormerod 1 that had never been used, only assembled. I've updated to dc42's most recent RC3 firmware. I can confirm on my Ubuntu laptop that the firmware is loaded across the serial monitor.

However, when I put in an SD card (I've tried two, sizes 32GB and 2GB ), I get a message from the Arduino IDE when starting the Serial Monitor that the port is unavailable. Removing the SD card and restarting the board results in the board communicating.

I'm currently simply connecting a USB cable directly from my laptop to the Duet 0.6 board. My first thought is to get a powered USB hub to make sure I'm getting enough power to the board, but I wanted to see if anyone had any other suggestions or if my board is bad.

Thanks!

There were rumors, that Duet 0.6 and 0.85 are no longer supported by RRF.
AFAIK, V1.20 was the last. Try using an older version, just to eliminate the chance you got an "unused" printer with a dead controller.

A small number of Duet 06/085 users have hit a bug (that I can't reproduce) which causes the Duet to keep resetting if you have networking enabled with all zeros in the IP address (meaning use DHCP). If that bug is affecting you, unplugging the Ethernet cable or setting a static IP address should work around it.

I plan to support RRF 1.21 on the 06/085.

Edited 1 time(s). Last edit at 03/03/2018 08:50AM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thanks for the responses.

I've tried the latest version released by RepRapPro and got the same issue.

The networking was enabled when I tried it yesterday. It was set to 0.0.0.0.

When I get back to it, I'll set a static IP and try it. For most of the time, I had the network cable disconnected.

David, if I do have a faulty board, are there less expensive controllers that will work with an Ormerod? I know some of the RAMPS board are cheaper, but I'd obviously have to use their firmware.

If you connect with no SD card inserted, then insert an SD card, do you lose the connection immediately? If so then it sounds like the card detect switch pin on the SD card socket is shorted to +3.3V. That should be fixable. You could even cut off the card detect pin from the SD card socket, because it isn't used on the older Duets because of a chip bug.

Edited 1 time(s). Last edit at 03/03/2018 12:47PM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

I'm fairly certain that the board stayed on when I put the card in after startup though I was unable to see any of the files.

I'll try again when I can.

If the board stays on when you insert the card, send command M21 to mount the card. After that you should be able to list the files.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Mounting the SD card after powerup seems to be working

I can list the files (only the gcodes dir) using M20. Also I've entered the network setup commands by hand and can get the web interface working.

I am having two more issues and I'm not sure if they stem from not reading the SD card or not. I can't get any temperature output, nor can I home the axes (or move them at all). Is there a command to read and execute the config.g and would that prevent movement?

Let me know if I need to start another post if this is a separate issue. Thanks!

If config.g has not been executed then the temperature sensors will not have been configured and the motor currents will be set to zero.

You can send:

M98 Pconfig.g

to execute config.g. If that causes the Duet to lose connection, binary-chop the commands in config.g until you find out which one is causing the problem. Or you can just list config.g, then send the commands one by one from the GCode Console.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Awesome, I actually put in the config.g by hand and got it to move. I'm glad there's a command for it. Thanks.

I'm working to do the commissioning now.

Should X0 Y0 be at the corner of the glass? When I home X, the probe is way off the bed so that when I try to home Z it never picks up the target under the glass as there is nothing there.

I tried to do i manually with a piece of paper and that seemed to work ok, but then trying to do the bed compensation it got the wrong positions when X was near 0.

You can use the M208 command to define the coordinates at which the homing switches are triggered, so as to set X0 Y0 at bed centre, ornate one corner of the bed, or anywhere else you want. Then in your homez.g and homeall.g files, move the head to the centre of the bed before doing the G30 probing command.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thanks for all the assistance.

I think I'm fairly close to being able to actually use the printer.

It seems to home the X axis wherever it happens to be, so that seems to be an issue.

The other thing I've seen is that the bed temperature sensor seems to lose connection. It goes from room temp to 2000 degrees. I touched the sensor wiring a couple of times and it will go in and out, so I'm guessing the connection to the bed is at fault. I'm going to disassemble the bed to investigate.

Lastly, when the Z axis moves, the gear that is connected to the threaded rod is very, very wobbly. I've even seen it bind a time or two when I'm running it up and down at a higher feed rate. I've asked a friend to reprint the gears, but it looks like the opening on the bottom is too large for the bearing. Is it possible the previous owner put the wrong size bearing there?

Again, thanks for all the help.

I suggest you ask these Ormerod specific questions on the Ormerod section of the forum.

Your X axis homing issue suggests that the proximity sensor is miswired, mis-configured or not working. With firmware 1.21RC you need a separate M574 command for the X axis.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Will do. Thanks for the suggestion.