Issues with my Mac detecting my serial USB converter

normandin17 · June 22, 2011, 2:23pm

I have a Mac and I just got the usb serial converter. I installed the updated drivers from plugable.com. My mac sees the device in the system profiler but when I use ZTerm to connect to a device all I get for options are “Bluetooth-PDA-Sync” and “Bluetooth-Modem” .

Lampros_Chaidas · June 22, 2011, 6:38pm

Hi!

Many thanks for your post! Sorry you’re having problems with our USB to Serial adapter on the Mac! Let’s see what we can do !

With the USB adapter connected, open up a terminal and type the following:
ioreg -c IOSerialBSDClient | grep usb
You should get something like this:

"IOTTYDevice" = "usbserial"   
"IOCalloutDevice" = "/dev/cu.usbserial"   
"IODialinDevice" = "/dev/tty.usbserial" ```   
 
What is the output of this command when you try it? If you're not getting anything it probably means the driver is not installed properly.   
 
\* What Mac OS X version do you have?   
\* When you go to 'System Preferences'-\>'Network'-\>is there a 'USB-Serial-Controller D' entry there?   
 
Once we have this information we can suggest next steps!   
 
Regards,   
Lampros

normandin17 · June 22, 2011, 9:43pm

Lampros, Thanks for the quick reply. This is what I get:

±o com_parallels_usb_control
I have Mac OS X 10.6.7. Nothing in the Networking for the USB Serial Controller. I tried to reinstall the driver and it just says I have a newer version installed already.

Thanks,

Mike

Lampros_Chaidas · June 22, 2011, 10:57pm

Mike,

Thanks for the reply. I think it’s a driver issue, you should definitely be seeing a device on Networking.

Let’s take a step back:
What is the device listed as in System Profiler? This is what we get on our Mac with 10.6.7:
!](https://sslproxy.getsatisfaction.com/sslproxy/SWhAdDNLMG5zdGFuVGlWenmLbJDGd3CABhjZermgcystANA4T6nd0pzV0fSzBRRGOd17A4b8ZLwi6-HESbXI0kSNOXlyIwuZT59sKYTX1sI4y32cuojOAZDt5CFUOudAbiSphlU0ohtNf_S0SN8y01mOlUVUi9EYkb547lELp6k=.png)](http://s3.amazonaws.com/satisfaction-production/s3_images/519746/serial_adapter-system_profiler.png)

Let’s uninstall the drivers:

Disconnect the device
Open up a terminal and type:
cd /System/Library/Extensions
Unload the driver:
sudo kextunload ProlificUSBSerial.kext
Delete the driver files:
sudo rm -r ProlificUSBSerial.kext

Let’s install the drivers: (With the device disconnected)

Install the drivers
Restart the computer as instructed after the installation is finished
Once the Mac has restarted and you’re logged in, plug in the adapter
Open the terminal again and try those 2 commands:
ioreg -c IOSerialBSDClient | grep usb
kextstat | grep prolific

What is the output of those 2 commands?
This is what we see on our system:
!](https://sslproxy.getsatisfaction.com/sslproxy/SWhAdDNLMG5zdGFuVGlWenmLbJDGd3CABhjZermgcystANA4T6nd0pzV0fSzBRRGOd17A4b8ZLwi6-HESbXI0oHSfF8lqK9KC0fplTvnJTlMX7cB5w0OR9VbGbf9-LCWcWmmiKLqZP0hgUIc-JFjBQ==.png)](http://s3.amazonaws.com/satisfaction-production/s3_images/519748/driver.png)

In System Preferences->Network->click the “+” sign to add a connection, do you see the USB-Serial Controller D under ‘Interface’?
This is what it should look like:
!](https://sslproxy.getsatisfaction.com/sslproxy/SWhAdDNLMG5zdGFuVGlWenmLbJDGd3CABhjZermgcystANA4T6nd0pzV0fSzBRRGOd17A4b8ZLwi6-HESbXI0tOTdd18_O3zfb3LOhfaDuXeoz6AtdyaF3Z-dujLXleBd0_yHXJK630l8YhzrUoA0jBcZXjeAI_UQKqYMbRHzjE=.png)](http://s3.amazonaws.com/satisfaction-production/s3_images/519750/serial_adapter-networking.png)

And finally on ZTerm:
!](https://sslproxy.getsatisfaction.com/sslproxy/SWhAdDNLMG5zdGFuVGlWenmLbJDGd3CABhjZermgcystANA4T6nd0pzV0fSzBRRGOd17A4b8ZLwi6-HESbXI0sa9irSmQqtUz2qRG-3jGecw0K2Xo_RSz-e7nCw1QzNxknGTeLjnIbae6QcLDtIQOLWzxYRSTyzhufER92RRkCc=.png)](http://s3.amazonaws.com/satisfaction-production/s3_images/519752/serial_adapter-zterm.png)

Let us know if this helps!
Regards,
Lampros

normandin17 · June 23, 2011, 2:06am

Here is what I get in my system profiler

!](https://sslproxy.getsatisfaction.com/sslproxy/SWhAdDNLMG5zdGFuVGlWenmLbJDGd3CABhjZermgcystANA4T6nd0pzV0fSzBRRGOd17A4b8ZLwi6-HESbXI0s6tvj9lYnKGeXyzy0cxFBZx-J-d7AdtXdmYUObSLgy3CL1pgcwiUmQU86HqtNXDNQuNtcM6oLikKqL4QBmrdlua5322xihOIBbTiAQAcITp.png)](http://s3.amazonaws.com/satisfaction-production/s3_images/519834/Screen_shot_2011-06-22_at_7.05.53_PM.png)

I will uninstall it and reinstall it per your instructions.

normandin17 · June 23, 2011, 2:08am

When I try to unload the driver I get this error:

(kernel) Kext com.prolific.driver.PL2303 not found for unload request.
Failed to unload com.prolific.driver.PL2303 - (libkern/kext) not found.

Does this mean I can bypass it and just delete it?

Lampros_Chaidas · June 23, 2011, 5:02pm

Hi Mike,

Step 3 sudo kextunload ProlificUSBSerial.kext is there simply to make sure that if the driver is currently loaded, unload it. The message you got means that the driver was not loaded at that moment. You may proceed with step 4 and delete the old drivers.

Let us know how it goes and if you need any help!

normandin17 · June 23, 2011, 10:42pm

Just like magic. Thank you it worked!

Lampros_Chaidas · June 23, 2011, 10:53pm

Hi Mike!

Thanks for letting us know! That’s great news!
Glad we could help!

Let us know if there’s anything else we can help with, we’re always here to help!

Regards,
Lampros

Zaikon · September 19, 2011, 2:29pm

Hello can i please have some help i found this the most usefull link across the internet but my case is at follows i click on the above link to install it following
Let’s install the drivers: (With the device disconnected)

Install the drivers
Restart the computer as instructed after the installation is finished
Once the Mac has restarted and you’re logged in, plug in the adapter

but always i get
USB-Serial Controller D:

Product ID: 0x2008
Vendor ID: 0x0557 (ATEN International Co. Ltd.)
Version: 3.00
Speed: Up to 12 Mb/sec
Manufacturer: Prolific Technology Inc.
Location ID: 0xfa130000 / 4
Current Available (mA): 500
Current Required (mA): 100

Is something wrong with the versions ??
i am running Software Mac OS X Server Lion 10.7.1 (11B2118)

e-lisi:Extensions root# kextunload ProlificUSBSerial.kext
(kernel) Kext com.prolific.driver.PL2303 not found for unload request.
Failed to unload com.prolific.driver.PL2303 - (libkern/kext) not found.
e-lisi:Extensions root# sudo kextunload ProlificUSBSerial.kext
(kernel) Kext com.prolific.driver.PL2303 not found for unload request.
Failed to unload com.prolific.driver.PL2303 - (libkern/kext) not found.

So to delete i just go to the recursive remove step mentioned above.

Roze_Padamadan · September 20, 2011, 12:35am

Hi Zaikon,

My guess is that the latest drivers that you are installing is not working because of the different Product ID and Vendor ID ( It is definitely not Plugable USB to RS-232 DB9 Serial Adapter that you are using ).

You should contact the manufacturer of the device to get the issue resolved but if you are unable to get help from them, then you could give the following steps a try and see if you can get this driver to work with your device-:

Install the drivers. (With the device disconnected)
Reboot the system as instructed after the installation is finished .
Launch the Terminal Window ( located in /Applications/Utilities/ )
Use the following command to open the Property List of the Prolific driver:
sudo nano /System/Library/Extensions/\ProlificUsbSerial.kext/Contents/Info.plist
Enter your admin password . This is necessary as the ProlificUsbSerial kernel extension is owned by root.
Find the ‘idProduct’ in the plist file . In the next line you would see an Integer value 8963 . Change it to 8200.
Right below that you see ‘idVendor’. In the line after that you would see an Integer value 1659. Change it to 1367.
Save the changes (Control-W) and quit (Control-X) nano
Use the following command to load the kernel extension:
sudo kextload /System/Library/Extensions/\ProlificUsbSerial.kext/Contents/Info.plist
Plug in the device to the system.

Do let us know if it fixes the issue for you.

Regards,
Roze

Zaikon · September 20, 2011, 3:07pm

Thanks a lot for the tip i just plugged in another serial cable i had and worked just fine

MarcEdwards · November 30, 2011, 6:18pm

Just bought a new Air running Lion. None of this worked after following explicitly. I get the error:

System/Library/Extensions/ProlificUsbSerial.kext/Contents/Info.plist failed to load - (libkern/kext) not found; check the system/kernel logs for errors or try kextutil(8).

I called support and they only had a 'Sorry no drivers for Lion." Has anyone figured this one out…

bernieplug · November 30, 2011, 7:56pm

Hi Marc - can you say what brand of USB serial adapter you have?

MarcEdwards · November 30, 2011, 11:12pm

http://www.aten.com/products/productI…

Jerome_Myers · December 1, 2011, 5:30pm

Hi Marc,

Unfortunately, that’s not one of Plugable’s products so we won’t be able to help. Sorry about that!!!

Best Wishes and Happy Holidays!!!

Jerome.

MarcEdwards · December 1, 2011, 11:36pm

Hi jerome:

No problems. I appreciate the response. I found this string in a google search and didn’t realize it was for a plug able adapter. Anyways, I went back to mfr. and found their installation for mac OSX. Works great! I did want to thank you as this is a great guide for setting up.

I will look into buying these in the future. Cheaper and great support!

Marc

Jerome_Myers · December 1, 2011, 11:43pm

Hi Marc,

Glad to hear you have a resolution!

Jerome.

Horatio · January 12, 2012, 6:48am

This thread has been really useful for me to understand the general concept of the driver. Unfortunately, it does not work for me: Ever since having switched to Lion, I cannot get the adapter to work. I followed all of the steps to install the driver, but I still get the following info from System Profiler (as far as I remember, plugging the adapter into keyboard or directly into the computer (screen) did not make a difference):

USB-Serial Controller:

Produkt-ID: 0x2303
Hersteller-ID: 0x067b (Prolific Technology, Inc.)
Version: 3,00
Geschwindigkeit: Bis zu 12 MBit/s
Hersteller: Prolific Technology Inc.
Standort-ID: 0xfa210000 / 4
Verfügbare Stromstärke (mA): 100
Erforderliche Stromstärke (mA): 100

Terminal provided the following info:

Macintosh:~ jhs$ kextstat | grep prolific
126 0 0xffffff7f80791000 0x8000 0x8000 com.prolific.driver.PL2303 (2.0.0)
Macintosh:~ jhs$ ioreg -c IOSerialBSDClient | grep usb
| | | “IOTTYBaseName” = “usbserial”
| | | “IOCalloutDevice” = “/dev/cu.usbserial”
| | | “IODialinDevice” = “/dev/tty.usbserial”
| | | “IOTTYDevice” = “usbserial”

Any idea what’s wrong? Shouldn’t the “Version” field in System Profiler read 4.00? Thanks and regards,
Jan

Jerome_Myers · January 13, 2012, 6:58pm

Hi Jan-Hendrik,

Thanks for posting your question, we be able to help. Here’s a link to the product page for our pl2303-db9. Can you verify that this is the product you have?

http://plugable.com/products/pl2303-db9/

Next, try the instructions at the following page and verify that the drivers have downloaded and installed correctly.

http://plugable.com/2011/07/12/instal…

If after these steps, your install is still not working, would it be possible to try the adapter on another system?

Post back with what you find and we’ll figure out next steps,
Thanks,
Jerome.

Plugable Technologies