Everyone's a Wally: Routine at B902

B902: Clear Play Area

Used by the routines at DrawRoom, ED2A, EDF7, EFC7 and F177.
Clear_PlayArea	B902	PUSH HL	Stash HL, BC and DE on the stack.
	B903	PUSH BC
	B904	PUSH DE
	B905	LD IX,$8248	IX=8248.
	B909	LD C,$98	C=98.
Clear_PlayArea_0	B90B	LD L,(IX+$00)	L=IX+00.
	B90E	LD H,(IX+$01)	H=IX+01.
	B911	LD B,$20	B=20.
Clear_PlayArea_1	B913	LD (HL),$00
	B915	INC HL
	B916	DJNZ Clear_PlayArea_1
	B918	INC IX
	B91A	INC IX
	B91C	DEC C
	B91D	JR NZ,Clear_PlayArea_0
	B91F	LD HL,$58A0	HL=58A0.
	B922	LD BC,$0260	BC=0260.
Clear_PlayArea_2	B925	LD (HL),$46	Write 46 to HL (INK: YELLOW, PAPER: BLACK (BRIGHT) ).
	B927	INC HL	Increment HL by one.
	B928	DEC BC	Decrease BC by one.
	B929	LD A,B	Jump to Clear_PlayArea_2 until BC is zero.
	B92A	OR C
	B92B	JR NZ,Clear_PlayArea_2
This entry point is used by the routine at Clear_Banner.
StackRestore	B92D	POP DE	Restore DE, BC and HL from the stack.
	B92E	POP BC
	B92F	POP HL
	B930	RET	Return.