Just in case, if anyone does not know that yet. NetBSD supports this, but not a graphical enviroment on Turbuchannel based systems :-(
Description:
TC-USB is a single-slot-width TURBOchannel USB host option based upon a Cypress (former ScanLogic) SL811HS USB 1.1 controller. It can be operated at typical TURBOchannel frequencies between 12.5 MHz and 25 MHz. A Lattice ispMACH 4000ZE family CPLD serves as glue logic for interfacing the 8-bit USB controller and 32-bit TURBOchannel. I/O read and write transactions and interrupts are supported. A basic option module ROM implemented in the CPLD compatible with TCF0 and TCF1 systems provides option information. The USB host port is an ESD-protected USB-A receptacle connector capable of sourcing 500 mA of current (limited) to devices.
http://www.flxd.de/tc-usb/
