Contact Sam Cruise: Routine at 78FC

78FC: Check whether a message is in the message queue

Used by the routines at 6100, 6177 and 790D. Returns with the zero flag set if the message whose number is stored at 7FD2 is present in the message queue (meaning it is currently being displayed or has yet to be displayed).
78FC	CALL $6EF4	Update the message line and process the message queue as appropriate
This entry point is used by the routine at 7996.
78FF	LD HL,$7FD2	Collect the message number stored at 7FD2
7902	LD A,(HL)	Collect the message number stored at 7FD2
7903	LD B,$08	There are 8 slots in the message queue
7905	LD L,$B8	HL=7FB8 (the first byte in the message queue)
7907	CP (HL)	Set the zero flag if the message number is in the queue
7908	INC HL	Point HL at the next byte in the message queue
7909	RET Z	Return if the message whose number is stored at 7FD2 is in the message queue
790A	DJNZ $7907	Jump back until all 8 bytes of the message queue have been checked
790C	RET