I am looking to make a switchbox for my 34 pin floppy drive (I know you can't hotswap) but I don't know what to use. I have heard of a multiplexer but I think it is only one way. I need to be able to switch the single "B" line from a DOS computer between a 5.25" floppy drive, and a floppy drive emulator. How can I achieve this?
You may actually be able to do a lot better than having to switch 34 wires. Take a look at the floppy connector pinout:
First of all, half of the wires are grounds, which you can just connect in parallel. Secondly, the cabling is actually designed for two drives to share the same cable, with a 'twist' in the cable to differentiate between the drives and all of the other connections wired in parallel. What goes through the twist are the drive select and motor enable signals. You might be able to get away with a simple DPDT switch to decide which drive gets connected to the drive select and motor enable signals, and connect all of the other signals to both drives.