MP 1,1-5,1 usb/serial problem with catalina patcher

[barneyntd]

I recently installed Catalina on my mac pro 3,1 (early 2008) using dosdude1's patcher, and I really like the result except for one thing: none of my usb/serial adaptors work. I have FTDI and CH340 devices which used to work before the install, and still work on a laptop with a supported Catalina install, but none of them work on my mac pro.

They appear in /dev when plugged in, and system report shows them correctly, but they won't communicate correctly either using CoolTerm or any device specific software such as bitscope-dso or avrdude.

Any ideas?

 

[barneyntd]

Well, I'm answering my own question, in case anyone searches for this. This seems to be the same problem noted on the open core wiki: the USB 1.1 drivers on mac pro 3,1 don't work properly. The workround is to connect USB 1 devices via a USB 2 hub, then they work.