I have looked and looked at this ttyACM0 thing with linux and tried just about every fix on the net I also have a Decimilia and Duemilanove running other projects, both of which work out of the box on the same system and default appropriately to /dev/ttyUSB0 - no issues. This is what happens on my xubuntu 12.04 system and UNO compatible - Freetronics Eleven. First - permissions set as recommended for groups and files. Next - Uno is selected as the board, and when it appears (not grayed out), serial port /dev/ttyACM0. From the beginning; Connect board to USB.
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Serial Port Programming in Embedded C (CS) Vidya-mitra. Programming in Visual Basic.Net How to Connect Access Database to. Java Project For Beginners Step By Step Using NetBeans And MySQL. Read from a Serial port, notifying when data arrives: COM Port « Development Class « Java. Import javax.swing.JLabel; import javax.swing.JPanel; /** * Read from a Serial port, notifying when data arrives. * Simulation of part of an event-logging service. } } } /** * Open a serial port using Java Communications. * * @author Ian.
Code: dmesg 1562.488131 usb 3-1: USB disconnect, device number 6 1570.049707 usb 3-1: new full-speed USB device number 7 using xhcihcd 1570.121549 usb 3-1: ep 0x82 - rounding interval to 1024 microframes, ep desc says 2040 microframes 1570.124259 cdcacm 3-1:1.0: ttyACM0: USB ACM device Open IDE (1.0 ubuntu installed or 1.0.1 in user folder) Serial port /dev/ttyACM0 with a tick But this is where the trouble starts; Select File (or File Sketchbook 'your favorite sketch') Serial port grayed out; and this. Code: dmesg 1611.679418 xhcihcd 0000:0c:00.0: ERROR no room on ep ring 1611.679423 cdcacm 3-1:1.1: acmsubmitreadurb - usbsubmiturb failed: -12 1611.679426 ttyportclosestart: tty-count = 1 port count = 0. 1615.390878 xhcihcd 0000:0c:00.0: ERROR no room on ep ring 1615.390893 cdcacm 3-1:1.1: acmsubmitreadurb - usbsubmiturb failed: -12 1615.390903 ttyportclosestart: tty-count = 1 port count = 0. Now disconnect USB and reconnect; Serial port /dev/ttyACM0 with a tick.
Compile and upload OK, except for. Code: avrdude: seropen: can't open device '/dev/tty/ACM0': Input/output error ioctl('TIOCMET'): Invalid argument Sometimes the error above doesn't show Now try selecting the Serial Monitor (bunch of Java errors). Serial port '/dev/tty/ACM0' not found (of course). Dmesg output same as previous failure.
This behaviour occurs when connecting and opening the IDE the first time. Second time around is unpredictable as to whether you even get to upload the script. As I see it, any attempt to use the IDE causes ttyACM0 to become unavailable. I guess, if I understand dmesg output correctly, writing to the device fails, I think?
Reading further, Kernel 3.4 (version from memory) should fix this. Apparently, it's a bug in 3.2, however, some people have found a fix. Interestingly, there is not a lot of consistency to each one. I have tried a lot of fixes on the net to no avail, except at one point I had it running smoothly. Then looked the other way and sneezed - and of course it broke.
Reapplying the previous 'fix' did not fix it. Hope there's enough here to help, but I guess it's old news anyhow. I know this post comes very late to the discussion, but I've spent days debugging problems with /dev/ttyACM0 under Linux (Ubuntu). I updated my BIOS, tried different kernels, and of course I'd double checked that my user account had read/write access to the device (because it was in the dialout group). The issue for me was modemmanager. On my laptop, modemmanager was grabbing the /dev/ttyACM0 somehow and causing contention.
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I got 'device or resource busy' messages; I got timeouts. I just got weird behavior in general, and almost always attempts to program failed. Because it was so hard to find, I'm coming back here to update this thread, which was fairly prominent when I tried to hunt down the issue. For me the fix was: $ sudo apt-get -purge remove modemmanager After that, things work as they should. On another laptop, modemmanager almost never caused a problem. Perhaps one in 25 times I had an issue. But on the laptop I use from day to day it was more like 99 out of 100 times it failed.