Can't Connect my Serial Device Through USB to Serial Adapter on Mac OSX 10.6.8!

I have just received and followed the installation instruction for USB Serial Adapter (1.5.0v) but I can’t connect to my serial device on my mac os x 10.6.8. Although I can when running a vm of windows 7 and everything works great. However the main software that I need to run is mac only.

System Profiler

USB-Serial Controller D:

Product ID: 0x2303
Vendor ID: 0x067b (Prolific Technology, Inc.)
Version: 4.00
Speed: Up to 12 Mb/sec
Manufacturer: Prolific Technology Inc.
Location ID: 0x1d100000 / 2
Current Available (mA): 500
Current Required (mA): 100


kextstat | grep prolific
0 0x841a7000 0x7000 0x6000 com.prolific.driver.PL2303 (1.5.0)


ioreg -c IOSerialBSDClient | grep usb
| | | “IOTTYBaseName” = “usbserial”
| | | “IOCalloutDevice” = “/dev/cu.usbserial”
| | | “IODialinDevice” = “/dev/tty.usbserial”
| | | “IOTTYDevice” = “usbserial”


ls /dev/*usbserial*
/dev/cu.usbserial /dev/tty.usbserial

I have also setup the network configuration for USB-Serial Controller D:
Vendor: Null Modem
Model: 9600 bps (This matches my device)
Error correction: Uncheck
Manual Dial
Sound: Off

Everything appears to be correct, just no luck.

Any help would be appreciated.


Thank you for posting your question about the USB to Serial adapter.

I agree, everything looks good, and the fact you can connect with a Windows in a VM tends to indicate things are running well at a hardware level.

What software are you using to connect to the device? Would it be possible to tell me what the serial device you are connecting to is?

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