ANSI/BHMA code F20 Entrance function.
Latch bolt retracted by lever/knob from either side unless outside is locked by
rotation of thumb turn inside. Deadbolt thrown or retracted by inside thumb turn
only. Throwing deadbolt locks outside knob/lever and free wheeling. When
outside is locked, latch bolt is retracted by key outside or by knob/lever inside.
Outside knob/lever remains locked and free wheeling until unlocked by
operating inside lever. Operating inside lever/knob retracts deadbolt and
latch bolt at the same time and unlocks outside lever/knob. Auxiliary latch
deadlocks latch bolt when door is closed. inside lever is always free for