This is also new for me. So here is what I did / found out. Until now, I ordered the "Quad-Flop" controller from Texelec and a (modified?) Gotek drive.
The Texelec seemed to be the most versatile option (and probably the only currently available option apart from tons of old random FDCs on ebay).
For the Gotek drive, the best option is one with an AT32F435 chip on it (there are also STM<something> - old and AT32F415 - less memory). There are versions of a Gotek drive on the internet, that are already modified for convinience:
- already flashed with
FlashFloppy (way better firmware)
- modified with a OLED display (instead of three LED digits)
- modified with a rotary knob
- modified with a speaker or buzzer for floppy sounds
In order to connect a floppy to the controller, you originally had to use a 34 pin floppy cable. There was a direct connection to the one drive (drive B / fd1), then a cable twist and a connector to the other drive (drive A / fd0). With the Gotek, I assume that we just need a straight cable, since the Gotek seems to have a Jumper for choosing between fd0 / fd1 and will probably "emulate" the cable twist.
The Gotek also has a 4-pin 3.5" power connector, and I need figure out where to take the 5V from, when everything arrived.
From the software side, the PC8477B controller on the Texelec is pretty common and compatible to the original NEC µPD765 controller (using port 3F0-3F7). Thats the single important thing when you need low-level compatibility in order to run old Minix, PC/IX, Xenix or whatever.
For the BIOS, the XT-IDE bios seems to support it - and the Texelec also has an optional BIOS. But BIOS is just software and thanks to Sergey, all the BIOSes are open source. If something doesn't work as expected, I feel confident enough to make it work.