Wheelie: Routine at 7311

7311: Routine at 7311

Used by the routine at 6C00.
7311	CALL $6B2D	Call 6B2D.
This entry point is used by the routine at 76D7.
7314	CALL $716E	Call 716E.
7317	LD HL,($7817)	HL=*7817.
731A	LD A,L	A=L.
731B	RLCA	RLCA.
731C	RLCA
731D	RLCA
731E	LD L,A	L=A.
731F	AND %00000111	Keep only bits 0-2.
7321	LD B,A	B=A.
7322	LD A,L	A=L.
7323	AND %11111000	Keep only bits 3-7.
7325	LD L,A	L=A.
7326	LD A,($7819)	A=*7819.
7329	ADD A,L	A+=L.
732A	LD L,A	L=A.
732B	LD A,H	A=H.
732C	LD H,$F8	H=F8.
732E	LD DE,$0800	DE=0800.
7331	SUB $99	A-=99.
7333	ADD HL,DE	HL+=DE.
7334	SUB $05	A-=05.
7336	JR NZ,$7333	Jump to 7333 if A is not zero.
7338	LD A,H	A=H.
7339	ADD A,B	A+=B.
733A	LD H,A	H=A.
733B	PUSH HL	Stash HL on the stack.
733C	LD DE,$0008	DE=0008.
733F	SBC HL,DE	HL-=DE (with carry).
7341	EX DE,HL	Exchange the DE and HL registers.
7342	LD HL,($7841)	HL=*7841.
7345	SBC HL,DE	HL-=DE (with carry).
7347	LD A,H	Jump to 736C if H is not zero.
7348	AND A
7349	JR NZ,$736C
734B	LD A,L	A=L.
734C	CP $50	Jump to 736C if A is higher than 50.
734E	JR NC,$736C	Jump to 736C if A is higher than 50.
7350	SUB $08	A-=08.
7352	SRA A
7354	LD C,$44	C=44.
7356	LD E,A	E=A.
7357	LD D,$0B	D=0B.
7359	LD A,$00	A=00.
735B	ADC A,$00
735D	CALL $76D7	Call 76D7.
7360	LD A,($7825)	Jump to 736C if *7825 is not equal to 44.
7363	CP $44
7365	JR NZ,$736C
7367	LD A,$01	Write 01 to *7840.
7369	LD ($7840),A	Write 01 to *7840.
736C	POP HL	Restore HL from the stack.
736D	LD A,($7840)	Return if *7840 is zero.
7370	AND A
7371	RET Z
7372	LD A,H	Return if H is not zero.
7373	AND A
7374	RET NZ
7375	LD A,L	Return if L is higher than 80.
7376	CP $80
7378	RET NC
7379	LD A,$80	A=80.
737B	SUB L	A-=L.
737C	NOP	No operation.
737D	NOP
737E	NOP
737F	NOP
7380	NOP
7381	LD C,$47	C=47.
7383	LD D,$0B	D=0B.
7385	SRA A
7387	LD E,A	E=A.
7388	LD A,$40	A=40.
738A	ADC A,$00
738C	CALL $76D7	Call 76D7.
738F	RET	Return.