The Hobbit: Routine at 84B9

84B9: Debounce keyboard

Used by the routines at GameOver and SaveGame.
DebounceAnyKey	84B9	XOR A	Read from the keyboard port.
	84BA	IN A,($FE)	Read from the keyboard port.
	84BC	AND %00011111	A pressed key from any line will set its respective bit; bit 0 (outer key) to bit 4 (inner key). Hence keep only bits 0-4 for the check.
	84BE	CP $1F	Loop back to DebounceAnyKey if a key is being pressed.
	84C0	JR NZ,DebounceAnyKey	Loop back to DebounceAnyKey if a key is being pressed.
NormalAnyKey	84C2	XOR A	Read from the keyboard port.
	84C3	IN A,($FE)	Read from the keyboard port.
	84C5	AND %00011111	A pressed key from any line will set its respective bit; bit 0 (outer key) to bit 4 (inner key). Hence keep only bits 0-4 for the check.
	84C7	CP $1F	Loop back to NormalAnyKey until any key has been pressed.
	84C9	JR Z,NormalAnyKey	Loop back to NormalAnyKey until any key has been pressed.
	84CB	RET	Return.