Problem with uploading sketches to arduino uno

Development Tools IDE 1.x
1

Hello,

I was wondering if anyone can help me with my problem. I already consulted the troubleshooting page and couldn't find much help. I have an arduino uno connected to my new macbook pro. The following message pops up when I try and upload an example sketch.

The message:

processing.app.SerialException: Serial port '/dev/tty.usbmodemfd121' 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/tty.usbmodemfd121' 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)

2

Are you using Processing or the Arduino application? Your error message suggests the former.

3

Verify you are not using Processing, as already suggested. If you are using the Arduino IDE (which is based on Processing, which may explain the debug messages if you are using Arduino IDE), then run the following in a terminal:

"lsof | grep usbmodemfd121"

lsof stands for "list of open files." In BSD (and other UNIX variants), which OSX is based on, most devices are actually an extension of the file system.

This will tell you what process has the device locked. (Typically it is the software for a wireless broadband device.)

4

I am using the arduino ide and not processing, but I do have it installed on my computer.

5

try what James C4S recommended, its probably some other application using the serial port.

6

for some reason the arduino ide isn't sending that message anymore. I put the "lsof | grep usbmodemfd121" in terminal and hit enter while my arduino ide was open but I got no response. But now, I get this message: avrdude: stk500_recv(): programmer is not responding. When I am trying to upload the blink sketch.