USB driver for serial comm (FTDI)

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Level 1

4 points

USB driver for serial comm (FTDI)

I’m on Mavericks (10.9.5) and fighting with a USB device with a “FT232R” chip (from FTDI) for USB to serial conversion.

It was not accessible in OS X (e.g. QuickTerm didn’t list it, only the Bluetooth Port + Modem).

Using an old Windows (in a Parallels VM on the same Mac) I could (and still can) access the device, switch it back and forth between OS X and Win, and send commands to it using a terminal SW.

In OS X it seems to be unknown, however, the USB Device Tree reports the FT232R USB UART correctly with Product ID and Vendor ID from FTDI.

But I want to get rid of the Win (VM) solution and installed the FTDI driver for Mac, didn’t work.

As suggested by FTDI for Mavericks

[ http://www.ftdichip.com/Support/Documents/AppNotes/AN_134_FTDI_Drivers_Installat ion_Guide_for_MAC_OSX.pdf ]

I have also disabled (renamed) the AppleUSBFTDI.kext, restarted and installed the FTDI driver (version 2.3, signed by Apple). The installer always tells me “success” but I still can’t see the driver /System/Library/Extensions/FTDIUSBSerialDriver.kext (should it be there?) and the device isn’t accessible from OS X.

I’ve tried again and again, there is no FTDI or USBSerial device listed in /dev when I plug it in or switch it back from Win - I guess because the (OS X) driver isn’t correctly installed?

Could someone help, please?

(I have little knowledge in OS X)

iMac, OS X Mavericks (10.9.5), USB serial adapter FTDI (FT232R)

Posted on Sep 5, 2016 3:50 PM

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Answer 1

Best reply

watski

Level 1

4 points

Jan 2, 2017 11:50 AM in response to SerCom

I am not sure if this will help but I had a similar problem after upgrading to Sierra. My FT232s would work after a reboot but if I disconnected and reconnected them they would not reappear. I installed the official FTDI drivers (v2.3), removed Apple's driver and rebooted.

sudo mv /Library/Extensions/FTDIKext.kext ~/

Now I can disconnect/reconnect my FT232 boards again 😀

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Answer 2

Feb 24, 2017 12:33 PM in response to SerCom

I have every symptom that the original poster mentions except I am using mac ox sierra 10.12.3.

I am using parallels running a windows 10 VM and the FTDI device that I'm using works fine there.

Can anyone shed light on this issue??

It seems that something changed in a mac os x update that causes a change in how FTDI devices must be configured.

It would be really nice to not require a windows 10 VM to get access to an FTDI USB to serial device.

To answer one if your initial questions about the difference between two of the folders for kernel extensions, I did find this from the kextload man pages.

FILES

/System/Library/Extensions/ The standard system repository of kernel extensions

/Library/Extensions/ The standard repository of non Apple kernel extensions

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Answer 3

Eric Root

Level 10

684,015 points

Sep 6, 2016 8:17 AM in response to SerCom

Does the drive show in Disk Utility? Can you reformat it to Mac OS Extended (Journaled)?

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Answer 4

SerCom Author

Level 1

4 points

Sep 6, 2016 2:24 PM in response to Eric Root

Thanks for attention!

Nope, not visible in Finder or Disk Utility, it’s not a drive, it won’t reply without a command.

The device is a test equipment with a serial port, originally RS232 (+/- 9V, DB-25). I’d send a (serial) “request” and the device will answer accordingly, e.g. transmit status info or accept commands.

I’ve adapted the electronics of that device (stripped the internal RS232 to TTL converter electronics for the uP, added the the USB socket and USB-TTL conversion with FT232R) to connect to modern computers.

It works with my Win - laptop and my (office) iMac (with an USB extender), but only when using the “Parallels” Win XP.

When I plug it into the iMac the VM automatically jumps in: “FT232 USB UART, new device detected, connect it to Mac or Win XP?”. Now I select “Mac” but nothing happens in OS X.

In the VM under “Devices” I can see the FT232 UART but connected to the Mac, and it’s not accessible in Win XP.

However, when I select the device from the VM “Devices” menu the VM tells me “FT232 UART is now connected to the Win XP” and I can send commands and receive statements from the test equipment. I also can hand it back to OS X but it's not recognized there.

Btw. also when the Parallels VM isn’t running the USBSerial doesn’t show up in /dev when I plug it in.

PS: This sounds similar with Yosemite (although my device definitely has an original FT232RQ chip):

http://arduino.stackexchange.com/questions/12133/mac-osx-yosemite-no-serial-port s-showing-for-uno-r3#

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Answer 5

SerCom Author

Level 1

4 points

Sep 7, 2016 3:18 PM in response to SerCom

I’ve run EtreCheck 3.0.3 (307) (it crashed twice when I was typing the “Problem description”?) and found probably related info:

(A) - EtreCheck reports:

/Library/Extensions

[not loaded] com.FTDI.driver.D2XXHelper (1.0 - SDK 10.11 - 2016-09-03)

[not loaded] com.FTDI.driver.FTDIUSBSerialDriver (2.3 - SDK 10.9 - 2016-09-03)

- and I can see:

/Library/Extensions/FTDIKext.kext

and

/Library/Extensions/FTDIUSBSerialDriver.kext

(but not any D2XXHelper file as one would expect from the EtreCheck report, anyway, the D2XXHelper.kext would block the desired VCP driver so it must not be installed / loaded)

(B) - From the FTDI Application Note AN_134:

“

5.4 The device cannot be accessed even though the deviceID is supported in FTDIUSBSerialDriver

An ownership or permissions problem is preventing the system from making the device accessible.

Check that the driver is owned by root and wheel. The most common symptom is the group for FTDIUSBSerialDriver is not wheel.
To change the group, login as root and perform the following script in a Terminal window (Go > Applications > Utilities > Terminal):

cd /system/library/extensions
chgrp -R wheel FTDIUSBSerialDriver.kext

Reboot for the change to take effect.

”

- From their “cd /system/library/extensions” I’d take they expect the FTDIUSBSerialDriver.kext to be installed under /systems/…, but it is not.

This might be an error in the FTDI document,

however, my /Library/Extensions/FTDIUSBSerialDriver.kext

already is reported as “root” and “wheel” (whatever that means - please help!) in Terminal.

Only EtreCheck reports it as [not loaded].

Is this part of the problem?

- What is the difference of the folders

/System/Library/Extensions (where FTDI wants me to change the group)

and

/Library/Extensions (wher the driver is located, but “not loaded”).

What are they used for? Where should the driver reside?

- Who should load the driver when I plug in the device or switch it back from the Parallels VM?

- FTDI has 2 different drivers for that devices: A VCP and a programming driver.

I want the VCP (UART) emulation, this FTDI driver “allows applications that use the POSIX programming interface to communicate with the device” (???).

The D2XX “uses FTDI’s programming interface to access advanced features of the chip” (I don’t need that at the moment).

The D2XXHelper must not be installed, otherwise the VCP wouldn’t work (says FTDI).

However, EtreCheck reports the D2XXHelper as [not loaded].

Should I try to disable / rename that D2XXHelper,

but where would I find it?

I’d really appreciate any hint!

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Answer 6

SerCom Author

Level 1

4 points

Sep 9, 2016 2:28 PM in response to SerCom

Bump! (?)

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Answer 7

Oct 14, 2016 4:36 PM in response to SerCom

You can check if the extension was installed correctly with `kextstat | grep FTDI` and it should show some information indicating that a kernel extension with designator com.FTDI.driver.FTDIUSBSerialDriver is loaded. From the sound of it, I don't think you need the DxxHelper; I don't remember ever using anything like that.

I sometimes have similar problems, usually because the device was closed or disconnected wrongly, and the FTDI driver will fail to load any more devices until I restart the computer. I don't have much more to offer beyond that, though.

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Answer 8

Dec 13, 2016 12:45 PM in response to SerCom

Not sure if you have figured this out or not.

Have you tried using the kextload command in terminal to load your driver?

ssudo kextload /Library/Extensions/FTDIUSBSerialDriver.kext

I have a device which requires disabling the AppleUSBFTDI driver as well. I don't use that kernel extension that you have, though.

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Answer 9

Eric Root

Level 10

684,015 points

Feb 25, 2017 8:23 AM in response to boochbrain

Does the drive have a name? Someone who was having similar problems posted that when they gave the drive a name, it became visible in the mac OS.

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