Disable the floppy A: drive?

Hi All,

Anyone know if it's possible to write asm code inside Delphi 2 to disable a
floppy drive?

        set bit 2 on interrupt 21h to disable irq6

I've attempted this in Delphi 2 using the asm construct within a button
procedure 'Diasble Floppy' but all I get is a fatal exception error and the
program crashes! -- I've done this with a DOS exe booted from the
autoexec.bat file but now I would like to run this inside windows 95!

The idea is to lock the floppy unless requested by a person with the
correct password.

Is anyone willing to help?