NetBSD has no driver for the Fintek F81232 (0x1934:0x0706) on any branch
-- not netbsd-11, not HEAD. The chip attaches as ugen(4) and you get no
/dev/ttyU*. It is the console bridge built into Protectli firewall
appliances, among other things.
This is a working driver, plus the protocol documentation that made it possible. Built, booted and used on real hardware: NetBSD 11.0/i386 on a Samsung NP-Q1U (Q1 Ultra, 2007 UMPC), talking to a pfSense 2.9.0 console.