Fully
Addressed
Devices
Initiative
FADI is an initiative for those who create new pieces of hardware containing legacy devices with well-known addresses. It says that even such devices should be fully addressed - that means all the 8 or 16 addressing bits and /M1 signal should be decoded.
For example, a new Kempston-compatible joystick interface (using eight bit addressed port 31) should detect A0 to A7, /M1, /IORQ, and /RD signals.
Another example - a new AY sound interface (using 16-bit addressed ports) should detect A0 to A15, /IORQ, /M1, /WR and (optionally - depending on usage) /RD signals.