Catalina - USB Serial Cables seem to be broken TL;DR - How do I make a USB Serial cable work on Catalina?

I work as an embedded software developer. I write software on small circuit boards like an Arduino or BeagleBone or RaspberryPi. You might know or hear the phrase: "JTAG DEBUGGER"

Every day I use various USB serial converters to do my work.

I just got a new (Nov 2019) MacBook Pro 1 week ago with a real escape key.

I can get SOME, but not all, USB serial things to work.

Knowns:

A) (TYPE_CDC_DEVICES) Some development boards (from ST Microsystems and Texas Instruments) implement what is known as a "USB CDC ACM" Serial port:

These CDC type devices seem to work.

B) (TYPE_CHIP_DEVICES) Others are what you would describe as a "USB Serial Cable" in some cases, the usb-chip that makes this work is built into the main board and is used to as a debugger.

This is an APPLE supplied driver.

These chips come from companies like: FTDI, and PROLIFIC (Apple has a driver for this), and MICROCHIP, and SILABS.

For example the FTDI driver FROM APPLE is here:

/System/Library/DriverExtensions/DriverKit.AppleUSBFTDI.dext

These CHIP type cables and boards DO NOT WORK.

I cannot open the serial device with my TERMINAL programs.
Such as: Screen, and CoolTerm and others.

C) I know the device is present, and the driver is loaded - I can see the device, but when I try to open the device I get various different errors.
(The exact error depends on the application I am using).

foo@bar /dev % ls -l /dev/*usb*
crw-rw-rw-  1 root  wheel   18,  27 Dec  1 16:33 /dev/cu.usbserial-534400
crw-rw-rw-  1 root  wheel   18,  29 Dec  1 16:33 /dev/cu.usbserial-534401
crw-rw-rw-  1 root  wheel   18,  26 Dec  1 16:33 /dev/tty.usbserial-534400
crw-rw-rw-  1 root  wheel   18,  28 Dec  1 16:33 /dev/tty.usbserial-534401
foo@bar /dev % 


D) Others have problems too - I am not alone.


http://community.m5stack.com/topic/1369/m5stickc-usb-driver-and-catalina
https://community.platformio.org/t/mac-usb-port-detected-but-wont-upload/8756


Trying to run screen as root does not help.

E) Tried "sudo chmod a+rwx /dev/tty.usb*"

PART 2 .... 

Often these USB chips have 2 interfaces, more specifically the FTDI2232.

Interface #0 - tends to be the JTAG debugger interface.

Interface #1 - tends to be the UART debug terminal.

I need both to work. But if I can't get the basic UART to work - I can't even start with the JTAG part.

I am stuck.
Just FYI, I have the same problem. Using Fusion it will work on e.g. a virtual Windows Machine. 

Another user has also posted this, but no replies on that thread. It appears to be a more general problem.

Update: I've been working on this for some days, but it might be working now. I am not quite sure what did the trick, however. 

I've installed/reinstalled the VCP driver found here. That didn't help. 

Then I also installed the D2xxHelper, which also didn't help. Actually it made it worse since this actually removed the device completely from /dev/cu.usbserialxxx. 

I then rebooted the Mac and the device was back and now actually working as it should. If it was necessary to install both or only one of the two and reboot, I do not know. Hope this helps you too.