serial port '/dev/tty.usbserial-A4001sOt' already in use. Try quitting any progr

running Mac os 10.5.8 PowerPC G5

have latest version of Arduino and FTDI drivers. I am using the Deicimila ATMega168. I have it correctly selected under “Board” and the tty port is selected under “Serial Port”. I have a solid green light and a blinking yellow LED at pin 13 when initially plugged in. I have tried plugging the USB cable into all the different ports on the tower with the same result.

I’ve tried various combinations of running Upload and pressing the reset button with the same error. I have unplugged and restarted the computer several times. I have opened the Firewall and allowed Arduino IDE as an exception.

I haven’t used this board on this computer before. I did get it working on the previous PowerPC I was using that ran 10.4.11.

Here is the verbose output from shift + Upload:

Binary sketch size: 1010 bytes (of a 14336 byte maximum)
processing.app.SerialException: Serial port ‘/dev/tty.usbserial-A4001sOt’ already in use. Try quiting any programs that may be using it.
at processing.app.Serial.(Unknown Source)
at processing.app.Serial.(Unknown Source)
at processing.app.debug.Uploader.flushSerialBuffer(Unknown Source)
at processing.app.debug.AvrdudeUploader.uploadViaBootloader(Unknown Source)
at processing.app.debug.AvrdudeUploader.uploadUsingPreferences(Unknown Source)
at processing.app.Sketch.upload(Unknown Source)
at processing.app.Sketch.exportApplet(Unknown Source)
at processing.app.Sketch.exportApplet(Unknown Source)
at processing.app.Editor$DefaultExportAppHandler.run(Unknown Source)
at java.lang.Thread.run(Thread.java:655)
processing.app.debug.RunnerException: Serial port ‘/dev/tty.usbserial-A4001sOt’ already in use. Try quiting any programs that may be using it.
at processing.app.debug.Uploader.flushSerialBuffer(Unknown Source)
at processing.app.debug.AvrdudeUploader.uploadViaBootloader(Unknown Source)
at processing.app.debug.AvrdudeUploader.uploadUsingPreferences(Unknown Source)
at processing.app.Sketch.upload(Unknown Source)
at processing.app.Sketch.exportApplet(Unknown Source)
at processing.app.Sketch.exportApplet(Unknown Source)
at processing.app.Editor$DefaultExportAppHandler.run(Unknown Source)
at java.lang.Thread.run(Thread.java:655)

Thanks for your help

Hmm, it might be that some other application really is using the port. Anything that connects to a USB peripheral could be doing it: bluetooth applications, mobile wifi dongle software, smartphone synching applications, etc. Find anything like that?

Or, maybe RXTX (the serial port library that Arduino uses) is trying to acquire a lock file (even though the version that comes with Arduino shouldn't). Do you have another RXTX installed somewhere? Like /Library/Java/Extensions?

I have the same error.

I still have it despite: - removing all serial port hardware and software - moving Java extensions per: http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1211165807/6 - changing the folder permissions per karman.homelinux.net/blog/archives/277 - restarting the computer - re-installing Arduino

I'm on a Mac, using a Nano v3.0 (328), and have previously used Arduino successfully with a Uno.

Matt

The only thing I have connected to the computer is the keyboard and the mouse. I don't know how to see what background processes are running on a Mac (what's Mac's version of the Windows Task Manager?).

I will try greennomad's troubleshooting suggestions and post my results.

Thanks

Alright, per the older forum page that addressed this issue, this fix worked for me: http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1211165807/6

In Terminal, I used the following commands:

$ sudo mkdir /var/lock $ sudo chmod 777 /var/lock

No idea what's going on here, but it worked. I can now upload sketches :)

Sadly, that doesn’t work for me.

I am able to get my Uno to work, but when I plug in my Nano (and change the Board accordingly), I still get this error:

Binary sketch size: 450 bytes (of a 30720 byte maximum)
processing.app.SerialException: Serial port ‘/dev/cu.ColumbusGPS-DevB’ already in use. Try quiting any programs that may be using it.
at processing.app.Serial.(Serial.java:144)
at processing.app.Serial.(Serial.java:76)
at processing.app.debug.Uploader.flushSerialBuffer(Uploader.java:75)
at processing.app.debug.AvrdudeUploader.uploadViaBootloader(AvrdudeUploader.java:93)
at processing.app.debug.AvrdudeUploader.uploadUsingPreferences(AvrdudeUploader.java:56)
at processing.app.Sketch.upload(Sketch.java:1603)
at processing.app.Sketch.exportApplet(Sketch.java:1568)
at processing.app.Sketch.exportApplet(Sketch.java:1524)
at processing.app.Editor$DefaultExportHandler.run(Editor.java:2293)
at java.lang.Thread.run(Thread.java:680)
processing.app.debug.RunnerException: Serial port ‘/dev/cu.ColumbusGPS-DevB’ already in use. Try quiting any programs that may be using it.
at processing.app.debug.Uploader.flushSerialBuffer(Uploader.java:99)
at processing.app.debug.AvrdudeUploader.uploadViaBootloader(AvrdudeUploader.java:93)
at processing.app.debug.AvrdudeUploader.uploadUsingPreferences(AvrdudeUploader.java:56)
at processing.app.Sketch.upload(Sketch.java:1603)
at processing.app.Sketch.exportApplet(Sketch.java:1568)
at processing.app.Sketch.exportApplet(Sketch.java:1524)
at processing.app.Editor$DefaultExportHandler.run(Editor.java:2293)
at java.lang.Thread.run(Thread.java:680)

greennomad: are you sure you're using the right serial port? /dev/cu.ColumbusGPS-DevB doesn't sound correct to me.

After reinstalling my operating system , I found the new FTDI drivers on their website and now it works.