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usb to rs232 mac connection


usb to rs232 mac connection



driver path:




Check the driver firs write:

ioreg -c IOSerialBSDClient | grep usb


JCG-MacMini:~ cgunver$ ioreg -c IOSerialBSDClient | grep usb

      |   | |             "IOTTYBaseName" = "usbserial"

      |   | |             "IOCalloutDevice" = "/dev/cu.usbserial"

      |   | |             "IODialinDevice" = "/dev/tty.usbserial"

      |   | |             "IOTTYDevice" = "usbserial"


Connect to the USB port with the following command followed by the router USB port speed:


macbook:user$ cd /dev

macbook:user$ ls -ltr /dev/*usb*

CG-MacMini:~ cgunver$ ls -ltr /dev/*usb*

crw-rw-rw-  1 root  wheel   17,   1 Dec 15 13:44 /dev/cu.usbserial

crw-rw-rw-  1 root  wheel   17,   0 Dec 15 13:53 /dev/tty.usbserial


screen /dev/tty.usbserial 9600


To Disconnect the OS X USB Console from the Terminal Window

Enter Ctrl+A followed by Ctrl+\





INSTALLING A USB SERIAL ADAPTER ON MAC OS XHome / ExperienceInstallingPlatformMacProductPL2303-DB9 /Installing a USB Serial Adapte ...

By Bernie ThompsonJuly 12, 2011117 commentsInstalling, Mac, PL2303-DB9

The easiest way to go about installing our Plugable USB to Serial adapter is by starting with the device.

  • If you want to verify that the adapter and the driver were installed properly click here

Connect the device to the Mac. Once connected click on the Apple icon and on ‘About This Mac’


Click on ‘More Info…’


Click on ‘USB’ on the left and on the ‘USB-Serial Controller D’
If all is well you should be seeing something like this:


Time to get the driver! Fire up Safari and browse to and scroll down to Mac.
Click on the ‘PL2303 MacOSX10.6 dmg’, the Safari Downloads window should come up:


Double click on the md_PL23-3_MacOSX10


Now double click on the PL2303_1.4.0.dmg to mount the image


Now double click on the PL2303_1.4.0 to start the installation


Once the installer comes up click ‘Continue’ to proceed.


Then ‘Select a Destination’ click on your desired drive and click ‘Continue’ to move forward


Now just click ‘Install’ to continue.


You may be asked of your username and password – enter them and click ‘OK’


You’ll get a warning about restarting the computer after the installation is complete. This is normal, click ‘Continue Installation‘.


Installing should start (takes a couple of minutes to complete)


When it’s done you should see this:


Click on ‘Restart’ to reboot the Mac.

 After you restart, check that everything has installed OK.
On the Mac there are two methods to determine this:

Method 1:
Click on ‘Applications’


Click on ‘Utilities’


Click on ‘Terminal’


kextstat | grep prolific
ioreg -c IOSerialBSDClient | grep usb
Your results should be very close to this:


Method 2:
Click on ‘System Preferences’


Click on ‘Network’


Now click on the ‘+’ sign on the bottom left, and then on the ‘Select the interface and enter a name for the new Service’ click on ‘Interface’ – you should be seeing the ‘USB-Serial Controller D’ there.


This will create a “Network” interface for a modem or serial port. Because it’s a serial port, it’ll say “Not Configured” and that’s normal:


From the “Advanced” button you can change default settings (usually not needed). And this won’t change the “Not Configured” message – that’s still ok.


Now finally, you need an application which will talk to the serial port. On Mac, the file which maps to the port is /dev/cu.usbserial. If you have a null modem cable and a terminal program on the other side, the Mac actually has a built-in terminal program called “screen” that you can use to test the connection.


Once that is up and connected (and if the serial ports are set to the same baud rate and paramters), you can type on either side and see the characters come across.


USB Serial on the Mac is a real melding of the very new and very old. If you have any trouble, just to see existing FAQs for Plugable’s USB Serial adapter.






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Article details
Article ID: 19
Category: How To
Date added: 2015-12-15 22:33:52
Views: 2511
Rating (Votes): Article rated 3.4/5.0 (5)

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