The Hobbit (v1.0): Routine at A7C6

A7C6: Character routine: Gollum asks his riddle

If Gollum (whose location is at C3B0) is in Bilbo's room and Bilbo is visible, he asks the riddle chosen at the start of the game (970B, C6EB), and $B5EA is set to show he is waiting for an answer.
A7C6	LD A,($C3B0)	A = Gollum's own location
A7C9	LD HL,$B5E6	Is Bilbo in the same room?
A7CC	CP (HL)	Is Bilbo in the same room?
A7CD	RET NZ	No: say nothing
A7CE	LD HL,$C012	Is Bilbo actually visible?
A7D1	BIT 7,(HL)	Is Bilbo actually visible?
A7D3	RET Z	No (he is wearing the ring): Gollum cannot see him to ask
A7D4	CALL $9C99	Dry run? Then stop here: it always works
A7D7	LD HL,($B5DF)	HL = the riddle chosen at the start of the game...
A7DA	INC HL	...moved on 2 bytes, to the riddle's own text
A7DB	INC HL	...moved on 2 bytes, to the riddle's own text
A7DC	LD E,(HL)	DE = the riddle's address
A7DD	INC HL
A7DE	LD D,(HL)
A7DF	PUSH DE	HL = that address
A7E0	POP HL	HL = that address
A7E1	CALL $A113	Gollum asks it
A7E4	LD A,$01	Remember that he is now waiting for the answer
A7E6	LD ($B5EA),A
A7E9	RET