I have been using a TRENDnet TU-S9 USB to serial adapter for a couple years.
When I upgraded OSX from 10.10 Yosemite to 10.11 El Capitan, it stopped working.
I've tried reinstalling the driver, but that did not fix it.
I ran ioreg -p IOUSB and could still see the device, which is a good sign.
...
+-o USB-Serial Controller D@14200000 <class AppleUSBDevice, id 0x100000533, registered, matched, active, busy 0 (6 ms), retain 11>
...
Unfortunately /dev does not contain tty.usbserial when my adapter is connected.
How do I get OSX to create /dev/tty.usbserial when I connect my adapter?
Best Answer
Prolific has a new driver out that works with El Cap: http://www.prolific.com.tw/US/ShowProduct.aspx?p_id=229&pcid=41