When I installed linux the floppy controller was disabled
in Bios because there was no floppy drive.
Now I want to add a floppy drive and have to enable the
controller.
System refuses to start anymore (seems logical to me)
I get a basic console but I am not familiar how to proceed from here.
How do I get the back to running again with the floppy added

Make sure your BIOS has a boot order setup and/or you have no diskette in the floppy drive. Boot order is typically something like Floppy then CD then Hard Drive. Maybe when you installed the floppy you accidentally changed it to not go to hard drive. Also if the floppy is first in boot order (or at least before the hard drive) and you have a diskette in it you'll usually see non-system disk messages.

Also if you have a tape drive or other device it may be they were using the floppy controller (if they weren't SCSI devices) and you have a conflict with the newly added floppy device.

Ooooops..... Stupid me, there was a disk in the drive
that I forgot to take out!!
Thanks for the hint