Mac OS X now comes with drivers for FTDI-based USB serial ports. Unfortunately, if you plug in a JTAG adapter, such as Amontec JTAGkey, you will get a serial port but CrossWorks won't be able to access the JTAG part of the adapter.
In order to correct this you must unload the FTDI drivers:
sudo kextunload -b com.FTDI.driver.FTDIUSBSerialDriver
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8 comments
I just ran into a new issue, hope that there is some one which can help. When I try to connect i get this error message "cannot open USB interface", I'm running OSX version 10.9.1.
The FTDI debugger is found in HW settings (see picture) and I can also see:
/dev/tty.usbserial-FTU2XLL3A
/dev/tty.usbserial-FTU2XLL3B
I have been able to use the NGX ARM debugger, but I think that my OS upgrade to 10.9.1 has done some thing.
It looks like they've renamed the driver in Mavericks - running the following command line to unload the serial driver worked for me:
sudo kextunload -b com.apple.driver.AppleUSBFTDI
Hmm not working, I have tried this link:
http://alvarop.com/2014/01/using-busblaster-openocd-on-osx-mavericks/
And got my "Lock-pick tiny 2" working which is a clone of the KT-LINK probe. But still no luck with the NGX device :-(
Hi Mads,
Could you elaborate? Are you getting the same error? Does the kextunload produce an error?
Regards,
Jon
Hi Jon
The unload is not complaining with errors, but crosswords still comes with "cannot open USB interface" error.
It's strange that the KT-LINK version works, it's also based on the FTDI chip.
Can I get some logs out of crossworks for you?
Hi Mads,
The error indicates that the USB interface cannot be opened - this is usually down to the device already being used (typically by the serial port device driver).
What is the output from
kextstat?Are the tty drivers still visible in the /dev directory?
The KT-Link might be working because it has a non-standard VID/PID and therefore not loading the serial driver.
It might be worth rebooting before running
kextunloadin case any of the other things you have tried have had an effect, also disconnect the KT-Link as well.Regards,
Jon
Hi Jon
I just solved the problem, there is loaded 2 FTDI drivers:
com.apple.driver.AppleUSBFTDI
com.FTDI.driver.FTDIUSBSerialDriver
I have now unloaded both drivers and the NXG JTAG adapter also works?
What if I have connected a Serial port using FTDI will that work now ?
Any way problem considered solved, thanks for the help :-)
Hi Mads,
With the FTDI serial driver unloaded, a FTDI serial port will not work (this is the disadvantage of the NGX device using the standard FTDI VID/PID) - I guess it could possibly be made to work by modifying the FTDI driver's Info.plist file or creating a codeless kext, it depends on how the device is configured.
Anyway, I'm glad you are up and running...
Regards,
Jon
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