New FT232 clones (FT232 is the most cloned pieces of silicon on Earth) have a mechanism to protect from "being killed" (FTDI DRIVERS ARE KILLING FAKE CHIPS): it simply doesn't allow write anything to it's configuration memory…"
I guess you can use 4049 inverter (I assume you already know that you need CD4049UB, and will set 5V on your FTDI and power up 4049 from 5V on of FTDI board).
But in my opinion the simplest solution could be to use a pair of NPN…"
I was not able to flash my FrSky D4R-II using FTDI USB cable on Windows 7 or Windows 8 (it doesn't recognize my receiver and doesn't show receiver UID #).
I was able to flash it only on Windows XP.
You should use FTDI driver's…"