How to release/reset serial port FTDI devices - Mac OSX
MacOS High Sierra 10.13.3 FTDI Driver Fix - January 31, 2018
By: Garrett Johnson Tired of your dev. boards not being recognized on your shiny new macbook? Are you blaming those damn C-ports?PROBLEM: FTDI devices not usable in MacOS High Sierra. In my own case, I was having trouble connecting FT232R chip devices to my 2016 Macbook Pro with C-Ports. The devices appeared in my USB device tree (System Information -> Hardware -> USB), but did not show up as a serial device using Arduino, or Coolterm. - NOTE: they did not appear either when in Terminal with the command (ls /dev/cu*) or (ls /dev/tty*)
SOLUTION:
3) Download the 2.4.2 drivers from FTDI's website http://www.ftdichip.com/Drivers/VCP.htm and install. The install will succeed, BUT due to Apples built-in FTDI drivers they will not work.
2) Reboot computer and enter recovery mode Via powering down and holding down CMD + R on reboot.
3) In recovery mode open terminal from utilities at the top of the screen and type the following to tempraily disable System Integrity Protection:
csrutil disable
The computer will prompt you to reboot to make changes take effect.
4) On reboot we now need to disable the Apple FTDI drivers (NOTE: this can be reversed at any time so do not worry). - open Terminal and type the following.
cd /system/library/extensions
sudo mv AppleUSBFTDI.kext AppleUSBFTDI.disabled
sudo touch /System/Library/Extensions
chgrp -R wheel FTDIUSBSerialDriver.kext
sudo mv D2zzHelper.kext D2xxHelper.disabled
Now you will have successfuly have disabled Apple's built-in FTDI drivers and replaced them with FTDI v2.4.
5) Restart your computer in recovery mode. Shutdown, hold Command + R and open terminal in the Utilities tab. Enter the following to reenable Apple's System Integrity Protection
csrutil enable
**NOTE: I have tested this on a 2016 Macbook Pro with MacOS 10.13.3 on the following devices/apps: 1) Screen from within terminal, CoolTerm, Bus Pirate V3.6, JTAGulator, Arduino Uno, Adafruit Mega AT, Arduino Mega clone.
I had the same issue, albeit on Sierra, talking to an Arduino Nano clone (which also uses a FTDI FT232RL bridge).
What seems to have worked for me is actually removing the FTDI driver (/Library/Extensions/FTDIUSBSerialDriver.kext), after finding that Apple ships an FTDI driver with the OS itself (/System/Library/Extensions/AppleUSBFTDI.kext).
I think having both drivers active at the same time causes a conflict, which ties up the USB port.
I'd like to provide an additional answer that solves one more piece of the puzzle that I had. Even following Garrett Johnson's excellent answer above, my FTDI driver was still not working. It turned out that - and I know this sounds insane - that my System Preferences "Security & Privacy" tab was not accepting my trackpad's click on the "Allow" button that would allow the driver to load. I got down this path after seeing this message in install log:
2018-09-15 16:21:04-04 host installd[1160]: kextcache: Kext rejected due to system policy: <OSKext 0x7f869ab80530 [0x7fff87e7aaf0]> { URL = "file:///Library/StagedExtensions/Library/Extensions/FTDIUSBSerialDriver.kext/", ID = "com.FTDI.driver.FTDIUSBSerialDriver" }
Of course, I clicked "Allow" in there, but nothing seemed to happen. The button registered the click, but I didn't have any window pop up or anything else for some form of confirmation. Searching around the Internets, I discovered this lengthy thread on Karabiner's github page discussing several solutions for forcing System Preferences to permit the mouse click:
https://github.com/tekezo/Karabiner-Elements/issues/1017
Apparently I had some software running that was intercepting the trackpad activity. It wasn't chrome in my case, unlike several people on that list. I have no clue what it was, which is a little concerning. The solution that worked for me was to enable Mouse Keys, then push "I" to click the mouse over the "Allow" button. At that point, a window popped up, and I was able to permit the FTDI driver to load.
I'm still shaking my head!