Arduino Uno R3 doesn't show up in Mac OS X (10.6.8) system with USB?

Hi,

I can't seem to get my newly acquired Arduino Uno (Rev. 3) board to show up on my Mac OS X ( 10.6.8 ) system reliably and now it's gotten to a point where it doesn't seem to show up at all. Until recently some combination of unplugging and re-plugging the board and the separate power supply would make it appear (as evidenced by a USB serial device showing up under /dev/tty.... and in the IDE) but now I seem to get only the following in the USB Prober application when I connect the board:

56.906 [1] [0x1c27be00] The IOUSBFamily is having trouble enumerating a USB device that has been plugged in. It will keep retrying. (Port 3 of Hub at 0xfd550000)
59.903 [1] [0x1c27be00] The IOUSBFamily was not able to enumerate a device.
60.747 [1] [0x1c27be00] The IOUSBFamily is having trouble enumerating a USB device that has been plugged in. It will keep retrying. (Port 3 of Hub at 0xfd550000)
64.143 [1] [0x1c27be00] The IOUSBFamily was not able to enumerate a device.
64.971 [1] [0x1c27be00] The IOUSBFamily is having trouble enumerating a USB device that has been plugged in. It will keep retrying. (Port 3 of Hub at 0xfd550000)
65.803 [1] [0x1c27be00] The IOUSBFamily gave up enumerating a USB device after 10 retries. (Port 3 of Hub at 0xfd550000)
65.803 [1] [0x1c27be00] The IOUSBFamily was not able to enumerate a device.

My understanding is that the Arduino Uno R3 doesn't need any USB drivers to be installed (although it shouldn't hurt). Just in case, I've tried installing the FTDI USB drivers (I downloaded FTDIUSBSerialDriver_v2_2_17.dmg) but that, indeed, didn't seem to make any difference.

Any idea what I'm missing? Has some part of the boot code on my board been overwritten? How can I get my Arduino to show up reliably?

Thanks in advance for any insights,
-Patrick.

Since there is no FTDI chip, one would expect no change in installing the drivers. You could install drivers for a laser cutter and get the same result.

It looks like the ATmega16u2 isn't enumerating. It could indicate corrupted firmware on the ATmega16u2. The ATmega328 is probably fine, since it isn't involved in USB enumeration.

Hi James,

That makes sense to me. Can I fix (re-load?) the firmware on the ATmega16u2? Is this a known problem? I have no idea how I might have ended up in this state, and I don't see anyone else puzzled by how to connect their Arduino Uno to a Mac?

Thanks!
-Patrick.

I have an R3 Uno and have no problems with it on my Mac. So there is something about your setup. The board has an ISP header for re-flashing the ATmega16u2 chip if it comes to that. First I would be simply checking if the firmware on it is what you expect.

A simple test would be to find another PC/Mac somewhere and try that.

Hi Nick,

A simple test would be to find another PC/Mac somewhere and try that.

That's a great idea! I tried it on another 10.6.8 system and it also didn't show up but, just in case, I tried it on a system that happened to be running 10.7. No idea why but the USB modem appeared as expected! What's more, since that test it's shown up without a problem on my original system, too! Maybe Mac OS X "Lion" has heretofore unknown curative powers :slight_smile:

Thanks to all who replied - aside from the occasional "Serial port in use" that I can manage, I think I'm totally back in business!

Best regards,
-Patrick.

"Serial Port in Use"

Can generally be fixed with:
$ sudo mkdir /var/lock
$ sudo chmod 777 /var/lock

Unless, of course, there is actually something keeping the serial port open.

I got the same issue, I try tons of thinghs, but the solucion was at bit of distance.
I just programm again the xxu2 (in my case the USB2SERIAL with 8u2 chip)

I leave here the link to use the dfu programmer (in mac)

https://github.com/arduino/Arduino/tree/master/hardware/arduino/firmwares/atmegaxxu2/arduino-usbserial