;
;  Disassembly of SD's DDBIOS ROM
;      ver. 4.2   (256b sects.)
;         rzh    2/14/92
;
cr		equ	0dh
lf		equ	0ah
;
		org     0f000h
;
bios:		NOP		;cold
		LD	E,0
;
		JP	0F063H	;warm
		JP	0E006H	;console status
		JP	0E009H	;console input
		JP	0E00CH	;console output
		JP	0F10AH
		db	0,0,0
		db	0,0,0
		JP	0F159H	;home
		JP	0F168H	;select
		JP	0F16DH	;track
		JP	0F172H	;sector
		JP	0F177H	;dma
		JP	0F17CH	;read
		JP	0F198H	;write
		JP	0F3B4H	;load
		JP	0F3C1H	;save
		JP	0F406H	;format

		db	22h,97h,26h
		db	21h,0ffh,0ffh
		db	22h,9ch,26h

;    8" single density

		db	26	;sectors/track
		db	77	;tracks/side
		db	100-27	;index header gap
		db	6	;gap 1
		db	11	;gap 2
		db	27	;gap 3
		db	8	;restore command
		db	1ah	;seek no verify cmd.
		db	1eh	;seek with verify

;    8" double density

		db	26	;sectors/track
		db	77	;tracks/side
		db	100-54	;index header gap
		db	8	;gap 1 (pre ID gap)
		db	22	;gap 2 (ID->data gap)
		db	54	;gap 3 (data->ID gap)
		db	0ah	;restore command
		db	1ah	;seek no verify cmd.
		db	1eh	;seek with verify

;    5" single density

		db	18	;sectors/track
		db	35	;tracks/side
		db	20-8	;index header gap
		db	6	;gap 1 (pre ID gap)
		db	11	;gap 2 (ID->data gap)
		db	8	;gap 3 (data->ID gap)
		db	0bh	;restore command
		db	1bh	;seek no verify cmd.
		db	1fh	;seek with verify

;    5" double density

		db	18	;sectors/track
		db	80	;tracks/side
		db	100-16  ;header gap bytes
		db	8	;gap 1 (pre ID gap)
		db	22	;gap 2 (ID->data gap)
		db	16	;gap 3 (data->ID gap)
		db	0bh	;restore command
		db	1bh	;seek no verify cmd.
		db	1fh	;seek with verify

warm:		LD	SP,80H
		IN	A,(7FH)
		LD	A,0
		LD	(42H),A
		LD	A,E
		CP	4
		JP	NC,0E803H
		PUSH	AF
		LD	A,0EFH
		PUSH	HL
		LD	(4DH),SP
		POP	HL
		RRCA
		JR	NC,0F099H
		OUT	(63H),A
		CALL	0F3A8H
		AND	4
		JR	Z,0F095H
		XOR	A
		OUT	(65H),A
		LD	A,2
		LD	(44H),A
		LD	A,1AH
		CALL	0F2FAH
		IN	A,(63H)
		JR	0F07CH

		POP	AF
		PUSH	AF
		CALL	0F159H
		POP	AF
		CALL	0F10AH
		JR	NZ,0F0BDH
		CALL	0F0C7H
		LD	HL,80H
		LD	A,(HL)
		AND	0CEH
		JR	NZ,0F0B4H
		BIT	0,(HL)
		JP	NZ,80H
		LD	A,31H
		LD	HL,0E800H
		CP	(HL)
		JP	Z,0E800H
		LD	A,0E0H
		LD	HL,0E002H
		CP	(HL)
		JP	Z,0E003H
		HALT
		LD	HL,80H
		LD	(40H),HL
		XOR	A
		LD	(44H),A
		INC	A
		LD	(43H),A
		CALL	0F17CH
		RET	Z
		JR	0F0BDH

		LD	A,(42H)
		LD	E,A
		LD	A,4
		DEC	A
		CP	B
		JR	Z,0F0F1H
		DEC	A
		CP	B
		JR	Z,0F0F8H
		DEC	A
		CP	B
		JR	Z,0F101H
		OR	1
		POP	HL
		RET

		LD	A,E
		AND	0FH
		LD	(42H),A
		RET

		LD	A,E
		AND	0FH
		OR	20H
		LD	(42H),A
		RET

		LD	A,E
		AND	0FH
		OR	60H
		LD	(42H),A
		RET

		LD	B,4
		AND	0FH
		OR	40H
		LD	(42H),A
		LD	HL,(40H)
		LD	(51H),HL
		CALL	0F13CH
		LD	HL,(51H)
		LD	(40H),HL
		LD	A,(42H)
		RET	NZ
		JR	NC,0F12AH
		SET	6,A
		LD	E,A
		LD	A,(49H)
		OR	A
		LD	A,E
		RES	4,A
		JP	P,0F137H
		SET	4,A
		LD	(42H),A
		XOR	A
		RET

		PUSH	BC
		PUSH	IX
		PUSH	HL
		LD	(4DH),SP
		POP	HL
		CALL	0F1D3H
		CALL	0F226H
		POP	IX
		POP	BC
		LD	A,(4BH)
		RRCA
		RET	Z
		DEC	B
		CALL	0F0DBH
		JR	0F13CH

		LD	(4DH),SP
		PUSH	IX
		CALL	0F1D3H
		CALL	0F1C7H
		POP	IX
		RET

		LD	A,C
		LD	(42H),A
		RET

		LD	A,C
		LD	(44H),A
		RET

		LD	A,C
		LD	(43H),A
		RET

		LD	(40H),BC
		RET

		LD	BC,301H
		LD	(56H),BC
		PUSH	IX
		LD	IX,(53H)
		PUSH	BC
		CALL	0F25CH
		POP	BC
		JR	Z,0F195H
		CALL	0F1B1H
		JR	0F189H

		POP	IX
		RET

		LD	BC,301H
		LD	(56H),BC
		PUSH	IX
		LD	IX,(53H)
		PUSH	BC
		CALL	0F2ADH
		POP	BC
		JR	Z,0F195H
		CALL	0F1B1H
		JR	0F1A5H

		DJNZ	0F1C6H
		LD	A,(57H)
		LD	B,A
		DEC	C
		JP	P,0F1C1H
		POP	AF
		POP	IX
		XOR	A
		INC	A
		RET

		PUSH	BC
		CALL	0F1C7H
		POP	BC
		RET

		LD	(4DH),SP
		LD	A,(IX+6)
		CALL	0F2FAH
		XOR	A
		RET

		LD	DE,42H
		LD	A,(DE)
		AND	60H
		LD	C,A
		LD	A,(DE)
		AND	3
		LD	B,A
		LD	A,1
		JR	Z,0F1E5H
		RLCA
		DJNZ	0F1E2H
		OR	C
		AND	7FH
		LD	B,A
		LD	A,C
		LD	IX,0F03FH
		CP	0
		JR	Z,0F20EH
		LD	IX,0F048H
		CP	40H
		JR	Z,0F20EH
		LD	IX,0F048H
		CP	0C0H
		JR	Z,0F20EH
		LD	IX,0F051H
		CP	20H
		JR	Z,0F20EH
		LD	IX,0F05AH
		LD	(53H),IX
		PUSH	BC
		POP	AF
		CPL
		OUT	(63H),A
		LD	A,(DE)
		LD	(55H),A
		CALL	0F249H
		IN	A,(64H)
		AND	80H
		JP	NZ,0F2D1H
		RET

		CALL	0F332H
		LD	HL,48H
		LD	BC,667H
		LD	A,0F8H
		LD	(46H),A
		CALL	0F365H
		LD	A,0C0H
		CALL	0F267H
		LD	A,(48H)
		CP	(IX+1)
		JP	NC,0F2EEH
		OUT	(65H),A
		XOR	A
		RET

		LD	A,(42H)
		BIT	5,A
		LD	A,27H
		JR	Z,0F254H
		LD	A,3CH
		LD	B,0
		DJNZ	0F256H
		DEC	A
		JR	NZ,0F254H
		RET

		CALL	0F28CH
		LD	A,88H
		CALL	0F280H
		LD	HL,(40H)
		LD	(4CH),A
		LD	DE,(4CH)
		PUSH	DE
		DI
		OUT	(64H),A
		JR	0F274H

		JR	0F276H

		INIR
		POP	DE
		LD	(4CH),DE
		EI
		JR	0F2C5H

		LD	H,A
		LD	A,(49H)
		LD	L,A
		AND	1
		LD	A,H
		RET	Z
		SET	1,A
		RET

		POP	HL
		LD	(4DH),SP
		PUSH	HL
		LD	A,(42H)
		LD	D,A
		LD	A,(55H)
		CP	D
		JR	Z,0F2A2H
		CALL	0F1D3H
		CALL	0F226H
		CALL	0F2E1H
		LD	A,0FEH
		LD	(46H),A
		JP	0F36CH

		CALL	0F28CH
		LD	A,0A8H
		CALL	0F280H
		LD	HL,(40H)
		LD	(4CH),A
		DI
		OUT	(64H),A
		JR	0F2C0H

		JR	0F2C2H

		OTIR
		EI
		CALL	0F332H
		IN	A,(64H)
		LD	D,A
		LD	A,(46H)
		AND	D
		RET	Z
		LD	A,D
		LD	(47H),A
		CALL	0F249H
		OR	1
		LD	SP,(4DH)
		CALL	0F7F6H
		RET

		CALL	0F21EH
		LD	A,(IX+1)
		LD	C,A
		LD	A,(44H)
		CP	C
		JR	C,0F2F2H
		LD	A,0FH
		JR	0F2D1H

		LD	C,A
		IN	A,(65H)
		CP	C
		RET	Z
		LD	A,(IX+8)
		LD	(4CH),A
		LD	B,0D2H
		DJNZ	0F2FFH
		CALL	0F332H
		LD	A,(44H)
		OUT	(67H),A
		LD	A,80H
		LD	(46H),A
		LD	A,(4CH)
		OUT	(64H),A
		LD	B,0AH
		DJNZ	0F315H
		CALL	0F2C5H
		CALL	0F249H
		LD	A,(4CH)
		CP	(IX+6)
		RET	Z
		IN	A,(64H)
		AND	10H
		JR	NZ,0F32EH
		IN	A,(65H)
		CP	C
		RET	Z
		LD	A,20H
		JR	0F2D1H

		LD	E,0
		PUSH	BC
		LD	C,2
		IN	A,(64H)
		AND	1
		JR	Z,0F35DH
		DJNZ	0F337H
		DEC	E
		JR	NZ,0F337H
		DEC	C
		JR	NZ,0F337H
		POP	BC
		IN	A,(63H)
		OR	80H
		OUT	(60H),A
		DJNZ	0F34CH
		IN	A,(60H)
		CALL	0F3A8H
		LD	A,(IX+6)
		CALL	0F2FAH
		LD	A,0FEH
		JR	0F330H

		POP	BC
		IN	A,(63H)
		OR	80H
		OUT	(63H),A
		RET

		IN	A,(63H)
		AND	7FH
		OUT	(63H),A
		RET

		LD	B,0
		LD	A,(IX+0)
		INC	A
		LD	C,A
		LD	A,(43H)
		CP	C
		JR	C,0F37DH
		LD	B,10H
		DEC	C
		SUB	C
		PUSH	AF
		CALL	0F392H
		POP	AF
		OUT	(66H),A
		LD	BC,8067H
		LD	A,(42H)
		BIT	6,A
		JR	Z,0F365H
		LD	B,0
		JR	0F365H

		IN	A,(63H)
		CPL
		LD	E,A
		AND	10H
		CP	B
		RET	Z
		LD	A,E
		AND	6FH
		OR	B
		CPL
		OUT	(63H),A
		LD	B,0D2H
		DJNZ	0F3A3H
		JP	0F226H

		LD	A,0D0H
		OUT	(64H),A
		LD	A,0AH
		DEC	A
		JR	NZ,0F3AEH
		IN	A,(64H)
		RET

		CALL	0F7F6H
		CALL	0F17CH
		RET	NZ
		CALL	0F3CEH
		JR	NZ,0F3B7H
		RET

		CALL	0F7F6H
		CALL	0F198H
		RET	NZ
		CALL	0F3CEH
		JR	NZ,0F3C4H
		RET

		LD	HL,(40H)
		LD	DE,80H
		LD	A,(42H)
		BIT	6,A
		JR	Z,0F3DEH
		LD	DE,100H
		ADD	HL,DE
		LD	(40H),HL
		LD	HL,45H
		DEC	(HL)
		RET	Z
		DEC	HL
		DEC	HL
		INC	(HL)
		LD	A,(49H)
		OR	A
		PUSH	IX
		LD	IX,(53H)
		LD	A,(IX+0)
		POP	IX
		JP	P,0F3FDH
		RLCA
		INC	A
		CP	(HL)
		RET	NZ
		LD	(HL),1
		INC	HL
		INC	(HL)
		OR	A
		RET

		CALL	0F7F6H
		LD	(51H),SP
		PUSH	IY
		PUSH	IX
		PUSH	HL
		LD	HL,800H
		LD	(40H),HL
		LD	(4DH),SP
		POP	HL
		CALL	0F1D3H
		CALL	Z,0F1C7H
		JR	NZ,0F455H
		CALL	0F45CH
		CALL	0F4CCH
		XOR	A
		CALL	0F500H
		PUSH	BC
		CALL	0F555H
		CALL	0F59FH
		POP	BC
		JR	NZ,0F43EH
		CP	(IX+1)
		JR	NZ,0F42CH
		LD	A,4CH
		LD	(44H),A
		IN	A,(63H)
		RES	5,A
		OUT	(63H),A
		LD	DE,55H
		LD	A,(DE)
		SET	5,A
		LD	(DE),A
		POP	IX
		POP	IY
		RET

		POP	IX
		LD	SP,(51H)
		RET

		LD	HL,(40H)
		LD	A,(IX+4)
		RRCA
		LD	A,4EH
		JP	NC,0F46AH
		LD	A,0FFH
		LD	E,A
		LD	B,(IX+2)
		CALL	0F4C7H
		LD	B,(IX+5)
		CALL	0F4C7H
		XOR	A
		LD	B,(IX+3)
		CALL	0F4C7H
		CALL	0F4C0H
		LD	A,0FEH
		LD	(HL),A
		INC	HL
		PUSH	HL
		EXX
		POP	DE
		EXX
		XOR	A
		LD	B,4
		CALL	0F4C7H
		LD	A,0F7H
		LD	(HL),A
		INC	HL
		LD	B,(IX+4)
		LD	A,B
		SRL	A
		INC	A
		LD	C,A
		LD	A,E
		CALL	0F4C7H
		LD	B,C
		XOR	A
		CALL	0F4C7H
		CALL	0F4C0H
		LD	A,0FBH
		LD	(HL),A
		INC	HL
		LD	B,80H
		LD	A,(42H)
		BIT	6,A
		JR	Z,0F4B6H
		LD	B,0
		LD	A,0E5H
		CALL	0F4C7H
		LD	A,0F7H
		LD	(HL),A
		INC	HL
		RET

		LD	A,E
		OR	A
		RET	M
		LD	A,0F5H
		LD	B,3
		LD	(HL),A
		INC	HL
		DJNZ	0F4C7H
		RET

		EXX
		LD	B,(IX+0)
		DEC	B
		EXX
		LD	DE,(40H)
		PUSH	HL
		OR	A
		LD	C,(IX+2)
		LD	B,0
		EX	DE,HL
		ADD	HL,BC
		EX	DE,HL
		SBC	HL,DE
		PUSH	HL
		POP	BC
		POP	HL
		PUSH	BC
		EX	DE,HL
		EXX
		EXX
		LDIR
		POP	BC
		PUSH	BC
		EXX
		DJNZ	0F4E8H
		EXX
		POP	BC
		EX	DE,HL
		LD	A,(42H)
		BIT	4,A
		LD	A,80H
		JR	NZ,0F4FDH
		XOR	A
		LD	L,A
		LD	H,L
		RET

		PUSH	HL
		PUSH	BC
		EXX
		POP	BC
		POP	HL
		PUSH	DE
		POP	IY
		PUSH	DE
		EX	AF,AF'
		LD	D,1
		LD	A,(IX+0)
		CP	1AH
		LD	A,1
		JR	Z,0F51DH
		LD	A,(IX+0)
		SRL	A
		INC	A
		JR	NC,0F544H
		EX	AF,AF'
		LD	(IY+0),A
		OR	L
		JP	P,0F52AH
		LD	(IY+1),H
		RES	7,A
		EX	AF,AF'
		LD	(IY+2),A
		PUSH	AF
		LD	A,(42H)
		BIT	6,A
		JR	Z,0F53BH
		LD	A,1
		LD	(IY+3),A
		POP	AF
		CP	(IX+0)
		JR	Z,0F551H
		ADD	IY,BC
		INC	A
		LD	E,A
		LD	A,1AH
		CP	(IX+0)
		LD	A,E
		JR	Z,0F51DH
		LD	A,D
		LD	D,E
		JR	0F51DH

		EX	AF,AF'
		POP	DE
		EXX
		RET

		PUSH	DE
		PUSH	BC
		EXX
		EX	AF,AF'
		POP	BC
		PUSH	DE
		LD	E,A
		LD	D,C
		LD	B,(IX+2)
		LD	C,67H
		LD	HL,(40H)
		LD	A,80H
		LD	(46H),A
		CALL	0F365H
		LD	A,(42H)
		BIT	6,A
		LD	A,0
		JR	Z,0F578H
		LD	A,1
		LD	(50H),A
		LD	A,0F4H
		LD	(4CH),A
		DI
		OUT	(64H),A
		LD	A,(50H)
		OTIR
		LD	B,D
		OTIR
		OR	A
		JR	Z,0F590H
		OTIR
		LD	B,D
		DEC	E
		JR	NZ,0F589H
		POP	DE
		POP	HL
		LD	A,(HL)
		OUT	(C),A
		DJNZ	0F596H
		EI
		EXX
		EX	AF,AF'
		RET

		EX	AF,AF'
		LD	A,2FH
		DJNZ	0F5A2H
		DEC	A
		JR	NZ,0F5A2H
		IN	A,(63H)
		OR	80H
		BIT	7,L
		JR	Z,0F5BFH
		BIT	0,H
		RES	0,H
		JR	NZ,0F5BFH
		INC	H
		RES	4,A
		OUT	(63H),A
		DJNZ	0F5BAH
		EX	AF,AF'
		CP	A
		RET

		SET	4,A
		OUT	(63H),A
		EX	AF,AF'
		INC	A
		CP	(IX+1)
		RET	Z
		LD	(44H),A
		PUSH	HL
		LD	(4DH),SP
		POP	HL
		DJNZ	0F5D2H
		EXX
		EX	DE,HL
		LD	A,(IX+7)
		CALL	0F2FAH
		EX	DE,HL
		EXX
		IN	A,(65H)
		LD	B,A
		LD	A,(44H)
		CP	B
		LD	B,0
		RET

		db	0ah
		db	0c3h,0ach,0bh
		db	21h,0a2h,26h
		db	7eh
		db	36h,0
		db	0c9h
		db	21h,0a0h,26h
		db	0beh
		db	0c9h
		db	0cdh,9ah,24h
		db	0cdh,4ch,16h
		db	3ah,83h

		LD	SP,80H
		LD	HL,0F65BH
		CALL	0F638H
		CALL	0F641H
		JR	NZ,0F62EH
		LD	A,L
		LD	(42H),A
		LD	A,H
		LD	(39H),A
		CALL	0F018H
		LD	IX,(53H)
		LD	A,(39H)
		CALL	0F67CH
		CALL	0F018H
		LD	HL,0F66EH
		CALL	0F638H
		JR	0F600H

		LD	C,'?'
		CALL	0F00CH
		CALL	0F6C6H
		JR	0F600H

		CALL	0F653H
		JP	NZ,0E741H
		JP	0E707H

		CALL	0F653H
		JP	NZ,0E79AH
		JP	0E760H

		CALL	0F653H
		JP	NZ,0E74DH
		JP	0E713H

		LD	B,A
		LD	A,(0E028H)
		CP	1
		LD	A,B
		RET

		db	'TEST#DRV# (TTDD)'
		db	': ',3
		db	lf,cr,'TASK DONE'
		db	cr,lf,3

		CP	0
		JP	Z,0F7D3H
		CP	5
		JR	Z,0F69EH
		JR	C,0F6E7H
		CP	0FFH
		RET	NZ
		LD	HL,0F694H
		CALL	0F638H
		CALL	0F641H
		JP	(HL)

		db	'ADDRESS: ',3

		CALL	0F033H
		RET

		LD	HL,0F6CFH
		CALL	0F638H
		LD	A,(4CH)
		CALL	0F7EEH
		LD	A,(47H)
		CALL	0F7EEH
		LD	A,(42H)
		CALL	0F7EEH
		LD	A,(44H)
		CALL	0F7EEH
		LD	A,(43H)
		CALL	0F64AH
		CALL	0F653H
		JP	NZ,0E72FH
		JP	0E6F5H

		db	'CMD STAT DRV TRK'
		db	' SCTR> ',3

		XOR	A
		LD	(44H),A
		INC	A
		LD	(43H),A
		JR	0F745H

		LD	HL,800H
		LD	(40H),HL
		CALL	0F02AH
		CALL	NZ,0F6A2H
		LD	HL,900H
		LD	(40H),HL
		CALL	0F027H
		CALL	NZ,0F6A2H
		LD	A,(39H)
		CP	2
		JR	Z,0F71FH
		PUSH	AF
		CALL	0F759H
		POP	AF
		CP	3
		JP	Z,0F7B0H
		CP	4
		JP	Z,0F7A0H
		LD	HL,43H
		INC	(HL)
		LD	A,(IX+0)
		PUSH	HL
		LD	HL,42H
		BIT	4,(HL)
		POP	HL
		JR	Z,0F730H
		RLCA
		INC	A
		CP	(HL)
		JR	NZ,0F745H
		LD	(HL),1
		INC	HL
		INC	(HL)
		LD	A,(IX+1)
		CP	(HL)
		JR	NZ,0F745H
		LD	(HL),0
		LD	C,'P'
		CALL	0F00CH
		CALL	0F006H
		JR	Z,0F750H
		CALL	0F009H
		CP	'.'
		RET	Z
		LD	A,(39H)
		CP	2
		JR	Z,0F6FDH
		JR	0F6F1H

		LD	HL,900H
		EX	DE,HL
		LD	HL,800H
		LD	A,(42H)
		BIT	6,A
		LD	B,80H
		JR	Z,0F76BH
		LD	B,0
		LD	A,(DE)
		CP	(HL)
		LD	A,0FFH
		LD	(47H),A
		JP	NZ,0F6A2H
		INC	HL
		INC	DE
		DJNZ	0F76BH
		LD	HL,38H
		LD	DE,800H
		LD	B,40H
		LD	A,(42H)
		BIT	6,A
		JR	NZ,0F78AH
		SLA	B
		LD	A,(HL)
		RRCA
		JR	C,0F78FH
		INC	DE
		LD	A,R
		LD	(DE),A
		INC	DE
		INC	DE
		DJNZ	0F78FH
		LD	A,(HL)
		RRCA
		JR	C,0F79DH
		INC	A
		LD	(HL),A
		RET

		XOR	A
		LD	(HL),A
		RET

		PUSH	HL
		LD	HL,42H
		LD	A,(HL)
		AND	0F0H
		LD	(HL),A
		LD	A,R
		NOP
		AND	1
		OR	(HL)
		LD	(HL),A
		POP	HL
		LD	A,(IX+0)
		INC	A
		LD	B,A
		LD	A,R
		AND	1FH
		OR	A
		JR	Z,0F7B0H
		LD	(43H),A
		CP	B
		JR	NC,0F7B0H
		LD	A,(IX+1)
		LD	B,A
		LD	A,R
		AND	7FH
		LD	(44H),A
		CP	B
		JR	NC,0F7C2H
		JP	0F745H

		CALL	0F018H
		LD	A,(IX+1)
		DEC	A
		OUT	(67H),A
		LD	A,(IX+7)
		OUT	(64H),A
		CALL	0F006H
		JR	Z,0F7D3H
		CALL	0F009H
		CP	'.'
		RET	Z
		JR	0F7D3H

		CALL	0F64AH
		LD	C,' '
		JP	0F00CH

		LD	A,0FFH
		LD	(55H),A
		RET

		db	0ffh,0ffh,0ffh,0ffh

		end