[z180-stamp-cpm3.git] / cbios / ldrbios.180

	title	'LDRBIOS for CP/M 3.0'\r
\r
    ; Port Address Equates\r
\r
	maclib z180reg.inc\r
	maclib config.inc\r
\r
    ; IDE Task File Register Definitions\r
\r
IDEDat	equ	IDEBASE+0	; Data Register\r
IDEErr	equ	IDEBASE+1	; Error Register\r
IDEFeat	equ	IDEBASE+1	; Feature Register\r
IDESCnt	equ	IDEBASE+2	; Sector Count\r
IDESNum	equ	IDEBASE+3	; Sector Number\r
IDECLo	equ	IDEBASE+4	; Cylinder Low\r
IDECHi	equ	IDEBASE+5	; Cylinder High\r
IDESDH	equ	IDEBASE+6	; Drive and Head\r
IDECmd	equ	IDEBASE+7	; Command / Status\r
\r
    ; IDE Hard disk commands:\r
\r
CmdHome	equ	10h		; Recalibrate\r
CmdRd	equ	20h		; Read Sector\r
CmdWr	equ	30h		; Write Sector\r
CmdInit	equ	91h		; Initialize Drive Params\r
CmdId	equ	0ECh		; Read ID\r
CmdSF	equ	0EFh		; Set Feature\r
\r
    ; Partition Table Structures\r
\r
PART_TYPE	equ	4\r
PART_START	equ	8\r
PART_SIZE	equ	12\r
\r
    ; Partition table id\r
    ; (see http://www.win.tue.nl/~aeb/partitions/partition_types-1.html)\r
\r
PARTID1_FAT16	equ	00EH\r
PARTID2_FAT16	equ	006H\r
PARTID_CPM	equ	052H\r
\r
\r
TIMEOUT	equ	1000\r
\r
cr	equ 13\r
lf	equ 10\r
\r
\r
	.z80\r
	cseg\r
\r
    ; BIOS Jump vector.\r
\r
?boot:	jp boot         ; initial entry on cold start\r
?wboot:	jp wboot	; reentry on program exit, warm start\r
\r
?const:	jp const	; return console input status\r
?conin:	jp conin	; return console input character\r
?cono:	jp conout	; send console output character\r
?list:	jp list 	; send list output character\r
?auxo:	jp auxout	; send auxilliary output character\r
?auxi:	jp auxin	; return auxilliary input character\r
\r
?home:	jp home 	; set disks to logical home\r
?sldsk:	jp seldsk	; select disk drive, return disk parameter info\r
?sttrk:	jp settrk	; set disk track\r
?stsec:	jp setsec	; set disk sector\r
?stdma:	jp setdma	; set disk I/O memory address\r
?read:	jp read 	; read physical block(s)\r
?write:	jp write	; write physical block(s)\r
\r
?lists:	jp listst	; return list device status\r
?sctrn:	jp sectrn	; translate logical to physical sector\r
\r
?conos:	jp conost	; return console output status\r
?auxis:	jp auxist	; return aux input status\r
?auxos:	jp auxost	; return aux output status\r
?dvtbl:	jp devtbl	; return address of device def table\r
?devin:	jp cinit	; change baud rate of device\r
\r
?drtbl:	jp getdrv	; return address of disk drive table\r
?mltio:	jp multio	; set multiple record count for disk I/O\r
?flush:	jp flush	; flush BIOS maintained disk caching\r
\r
?mov:	jp move 	; block move memory to memory\r
?tim:	jp time 	; Signal Time and Date operation\r
?bnksl:	jp bnksel	; select bank for code execution and default DMA\r
?stbnk:	jp setbnk	; select different bank for disk I/O DMA operations.\r
?xmov:	jp xmove	; set source and destination banks for one operation\r
\r
	jp 0		; reserved for future expansion\r
	jp 0		; reserved for future expansion\r
	jp 0		; reserved for future expansion\r
\r
;----------------------------------------------------------------------\r
\r
hwini_tab:\r
	db	(hwini0_e-$)/2	;count\r
	db	rcr,CREFSH	;configure DRAM refresh\r
	db	dcntl,CWAITIO	;wait states\r
	db	ccr,M_NCD	;No Clock Divide\r
	db	cmr,PHI_X2	;X2 Clock Multiplier\r
	db	omcr,~M_IOC	;Operation Mode Control Register\r
				;MMU\r
	db	cbr,SYS$CBR	;Common Base Register\r
	db	cbar,USR$CBAR	;Common Base Area Register\r
				;ASCI0\r
	db	asext1,0	;disable BRG\r
	db	stat1,00000000b	;disable RX, TX interrupt, disable CTS1\r
	db	cntlb1,10000000b;PS:10 DR:16 Rate:1  --> BR = Phi/160\r
	db	cntla1,01100101b;RE TE RTS:0 8N2\r
hwini0_e:\r
	db	0		;stop mark\r
	db	0,0,0,0,0,0,0,0	;\r
\r
msg_boot:\r
	db cr,lf,'CPMLDR error: Unable to locate CP/M partition',cr,lf,0\r
\r
;-------------------------------------------------------------------------------\r
\r
    ; CP/M 3 Disk definition macros\r
\r
	maclib cpm3slr.lib	; dpb mcaro\r
\r
    ; The dph macro from the lib depends on GENCPM\r
\r
dphldr macro ?trans,?dpb,?csize,?asize,?dirbcb,?dtabcb\r
    local ?csv,?alv\r
	dw ?trans		; translate table address\r
	db 0,0,0,0,0,0,0,0,0	; BDOS Scratch area\r
	db 0			; media flag\r
	dw ?dpb			; disk parameter block\r
    if nul ?csize\r
	dw 0			; permanently mounted, no checksum vector\r
    else\r
     if ?csize = 0\r
	dw 0\r
     else\r
	dw ?csv			; checksum vector\r
     endif\r
    endif\r
    if nul ?asize\r
	dw 0			; no alloc vector\r
    else\r
     if ?asize = 0\r
	dw 0\r
     else\r
	dw ?alv			; allocation vector\r
     endif\r
    endif\r
	dw ?dirbcb\r
	dw ?dtabcb\r
	dw 0ffffh		; no hash\r
	db 0			; hash bank\r
    if not nul ?csize\r
     if ?csize <> 0\r
?csv	ds	?csize		; checksum vector\r
     endif\r
    endif\r
    if not nul ?asize\r
     if ?asize <> 0\r
?alv	ds	?asize		; allocation vector\r
     endif\r
    endif\r
    endm\r
\r
;-------------------------------------------------------------------------------\r
\r
	; dphldr translate$table,	- disk parameter header\r
	;	 disk$parameter$block,\r
	;	 checksum$size,			(optional)\r
	;	 alloc$size			(optional)\r
	;	 dir$bcb\r
	;	 data$bcb\r
dph0:\r
	dphldr 0,dpbsimhd512,0,0,bcb,bcb\r
\r
bcb:\r
	db	0ffh\r
	rept 9\r
	 db	0\r
	endm\r
	dw	buffer\r
\r
	; dpb	physical$sector$size,	- disk parameter block\r
	;	physical$sectors$per$track,\r
	;	number$tracks,\r
	;	block$size,\r
	;	number$dir$entries,\r
	;	track$offset,\r
	;	checksum$vec$size		(optional)\r
\r
dpbsimhd512:\r
	dpb 512,8,2048,4096,1024,6,8000h\r
\r
;-------------------------------------------------------------------------------\r
\r
wboot:                  ; jump vector locations not used\r
const:\r
conin:\r
list:\r
auxout:\r
auxin:\r
write:\r
listst:\r
conost:\r
auxist:\r
auxost:\r
devtbl:\r
cinit:\r
getdrv:\r
multio:\r
flush:\r
time:\r
bnksel:\r
setbnk:\r
xmove:\r
	ret\r
\r
;-------------------------------------------------------------------------------\r
; output bytes to ports\r
;\r
;     hl: tables of port,value pairs:\r
;         db n, port1,val1, port2,val2,... portn,valn\r
;         ...\r
;         db 0 ; Terminate table\r
\r
ioini1l:\r
	push	bc\r
	jr	io1_nxt\r
io1_lp:\r
	ld	c,(hl)		;port address\r
	inc	hl\r
	otim\r
	jr	nz,io1_lp\r
io1_nxt:\r
	ld	b,(hl)		;count\r
	inc	hl\r
	inc	b\r
	djnz	io1_lp\r
\r
	pop	bc\r
	ret\r
\r
;-------------------------------------------------------------------------------\r
; print message @<HL> up to a null\r
\r
?pmsg:\r
	ld a,(hl)\r
	or a\r
	ret z\r
	ld c,a\r
	push hl\r
	call ?cono\r
	pop hl\r
	inc hl\r
	jr ?pmsg\r
\r
;-------------------------------------------------------------------------------\r
\r
boot:\r
	; Init CPU, MMU, ASCI0\r
\r
	ld	hl,hwini_tab\r
	call	ioini1l\r
\r
	; Init disk partition\r
\r
	call	read_parttbl\r
	or	a\r
	jr	nz,boot_err\r
\r
	; check_signature\r
\r
	ld	hl,buffer+512-1\r
	ld	a,0aah\r
	cp	(hl)			; Test, if it has a valid MBR\r
	jr	nz,boot_err\r
	dec	hl\r
	cpl				; a=055h\r
	cp	(hl)			;\r
	jr	nz,boot_err\r
\r
	; Find CP/M paartition\r
	; Look for first CP/M partition and save partition offset\r
\r
	ld	hl,buffer+512-2-64+PART_TYPE	; Point to  partition type of first first partition table entry\r
	ld	de,16\r
	ld	b,4			; Max # of partition table entries\r
ploop:\r
	ld	a,PARTID_CPM\r
	sub	(HL)			; Test for CP/M Partition\r
	jr	nz,pnext\r
	ld	bc,4\r
	add	hl,bc			; Point to partition start (lba)\r
	ld	de,ptab_start\r
	ldir\r
	ret				;a=0\r
\r
pnext:\r
	add	hl,de\r
	djnz	ploop\r
\r
boot_err:\r
	ld	hl,msg_boot\r
	call	?pmsg\r
halt_loop:\r
	halt\r
	jr	halt_loop\r
\r
;-------------------------------------------------------------------------------\r
\r
conout:\r
	in0	a,(stat1)\r
	and	M_TDRE\r
	jr	z,conout\r
	out0	(tdr1),c\r
	ld	a,c\r
	ret\r
\r
;-------------------------------------------------------------------------------\r
\r
move:\r
	ex de,hl                ; we are passed source in DE and dest in HL\r
	ldir                    ; use Z80 block move instruction\r
	ex de,hl                ; need next addresses in same regs\r
	ret\r
\r
;-------------------------------------------------------------------------------\r
; Select Disk Drive.\r
; Return address of disk parameter header in <HL>\r
\r
seldsk:\r
	ld hl,dph0\r
	ret\r
\r
; Home selected drive.  Treated as SETTRK(0).\r
\r
home:\r
	ld	bc,0		; same as set track zero\r
\r
; Set Track. Saves track address from <BC> in @trk.\r
\r
settrk:\r
	ld	(@trk),bc\r
	ret\r
\r
; Set Sector.  Saves sector number from <BC> in @sect.\r
\r
setsec:\r
	ld	(@sect),bc\r
	ret\r
\r
; Set Disk Memory Address.  Saves DMA address from <BC> in @dma.\r
\r
setdma:\r
	ld	(@dma),bc\r
	ret\r
\r
; Translate sector address. Not needed. Return physical=logical.\r
\r
sectrn:\r
	ld	l,c\r
	ld	h,b\r
	ret\r
\r
;-----------------------------------------------------------------\r
\r
chk_to:\r
	xor	a	;\r
to_l:\r
	dec	a\r
	jr	nz,to_l	;\r
	dec	hl	; 4\r
	ld	a,h	; 4\r
	or	l	; 4\r
	ret	nz	; 10/5\r
	ccf		; 3\r
	ret		; 9\r
\r
;-------------------------------------------------------------------------------\r
; Wait for ready signal with time out\r
;     return:\r
;	 a = 0 if ok\r
;	 a = ff if timeout\r
\r
wait_rdy_to:\r
	push	hl\r
	ld	hl,TIMEOUT\r
wrdy_l:\r
	in	a,(IdeCmd)\r
	xor	01000000b\r
	and	11000000b	; clears carry\r
	jr	z,wrdy_e\r
	call	chk_to\r
	jr	nc,wrdy_l\r
wrdy_e:\r
	pop	hl\r
	sbc	a,a\r
	ret\r
\r
\r
;-------------------------------------------------------------------------------\r
\r
do_ide_cmd:\r
	out	(IdeCmd),a	;\r
	call	wait_rdy_to\r
	ret	c\r
	in	a,(IdeCmd)\r
	and	10001001b	;\r
	ret\r
\r
\r
;-------------------------------------------------------------------------------\r
; Read partition table\r
\r
read_parttbl:\r
	ld	hl,ptab_start\r
	ld	b,8\r
rp_l:\r
	ld	(hl),0\r
	inc	hl\r
	djnz	rp_l\r
\r
	ld	hl,buffer\r
	ld	(@dma),hl\r
\r
;	fall thru\r
\r
;-------------------------------------------------------------------------------\r
; Read a sector\r
\r
; compute logical block number (lba) --> cf-controller\r
\r
	; TODO: sectors per track from dpb\r
	; lba = track * 8 + sector\r
\r
read:\r
	ld	iy,ptab_start\r
	xor	a\r
	ld	hl,(@trk)\r
	add	hl,hl\r
	adc	a,a		; *2\r
	add	hl,hl\r
	adc	a,a		; *4\r
	add	hl,hl\r
	adc	a,a		; *8\r
	ld	de,(@sect)\r
	add	hl,de\r
	adc	a,0\r
	ld	e,a\r
	call	wait_rdy_to\r
	ld	a,(iy+0)	; add partition start\r
	add	a,l\r
	out	(IdeSNum),a\r
	ld	a,(iy+1)\r
	adc	a,h\r
	out	(IdeCLo),a\r
	ld	a,(iy+2)\r
	adc	a,e\r
	out	(IdeCHi),a\r
	ld	a,(iy+3)\r
	adc	a,0\r
	and	00FH\r
	or	0E0H\r
	out	(IdeSDH),a\r
	ld	hl,(@dma)\r
\r
	ld	a,1		; number of sectors to read\r
	out	(IdeSCnt),a	; set sector count\r
\r
	ld	a,CmdRd\r
	out	(IdeCmd),a	; command: read sector data\r
	ld	bc,IdeDat	; I/O address\r
wdrq:\r
	in	a,(IdeCmd)	; wait for DRQ to become active\r
	bit	3,a\r
	jr	z,wdrq\r
	inir			; read 512 data bytes (2 x 256)\r
	inir\r
wnb:				; wait while busy\r
	in	a,(IdeCmd)	;\r
	rlca\r
	jr	c,wnb\r
	rrca			; restore status\r
	and	10001001b	; Busy, DRQ, or Error?\r
	ret	z		; return 0, if everything is ok\r
	ld	a,1\r
	ret\r
\r
;-------------------------------------------------------------------------------\r
\r
ptab_start:\r
	dw	0,0\r
@trk:	dw	0\r
@sect:	dw	0\r
@dma:	dw	0\r
\r
buffer:\r
	end\r
Commit	Line	Data
88c783bb L	1	title 'LDRBIOS for CP/M 3.0'\r
	2	\r
	3	; Port Address Equates\r
	4	\r
3c56f4c2 L	5	maclib z180reg.inc\r
3c56f4c2 L	6	maclib config.inc\r
88c783bb L	7	\r
	8	; IDE Task File Register Definitions\r
	9	\r
	10	IDEDat equ IDEBASE+0 ; Data Register\r
	11	IDEErr equ IDEBASE+1 ; Error Register\r
	12	IDEFeat equ IDEBASE+1 ; Feature Register\r
	13	IDESCnt equ IDEBASE+2 ; Sector Count\r
	14	IDESNum equ IDEBASE+3 ; Sector Number\r
	15	IDECLo equ IDEBASE+4 ; Cylinder Low\r
	16	IDECHi equ IDEBASE+5 ; Cylinder High\r
	17	IDESDH equ IDEBASE+6 ; Drive and Head\r
	18	IDECmd equ IDEBASE+7 ; Command / Status\r
	19	\r
	20	; IDE Hard disk commands:\r
	21	\r
	22	CmdHome equ 10h ; Recalibrate\r
	23	CmdRd equ 20h ; Read Sector\r
	24	CmdWr equ 30h ; Write Sector\r
	25	CmdInit equ 91h ; Initialize Drive Params\r
	26	CmdId equ 0ECh ; Read ID\r
	27	CmdSF equ 0EFh ; Set Feature\r
	28	\r
	29	; Partition Table Structures\r
	30	\r
	31	PART_TYPE equ 4\r
	32	PART_START equ 8\r
	33	PART_SIZE equ 12\r
	34	\r
	35	; Partition table id\r
	36	; (see http://www.win.tue.nl/~aeb/partitions/partition_types-1.html)\r
	37	\r
	38	PARTID1_FAT16 equ 00EH\r
	39	PARTID2_FAT16 equ 006H\r
	40	PARTID_CPM equ 052H\r
	41	\r
	42	\r
	43	TIMEOUT equ 1000\r
	44	\r
	45	cr equ 13\r
	46	lf equ 10\r
	47	\r
	48	\r
	49	.z80\r
	50	cseg\r
	51	\r
	52	; BIOS Jump vector.\r
	53	\r
	54	?boot: jp boot ; initial entry on cold start\r
	55	?wboot: jp wboot ; reentry on program exit, warm start\r
	56	\r
	57	?const: jp const ; return console input status\r
	58	?conin: jp conin ; return console input character\r
	59	?cono: jp conout ; send console output character\r
	60	?list: jp list ; send list output character\r
	61	?auxo: jp auxout ; send auxilliary output character\r
	62	?auxi: jp auxin ; return auxilliary input character\r
	63	\r
	64	?home: jp home ; set disks to logical home\r
	65	?sldsk: jp seldsk ; select disk drive, return disk parameter info\r
	66	?sttrk: jp settrk ; set disk track\r
	67	?stsec: jp setsec ; set disk sector\r
	68	?stdma: jp setdma ; set disk I/O memory address\r
	69	?read: jp read ; read physical block(s)\r
	70	?write: jp write ; write physical block(s)\r
71	\r
72	?lists: jp listst ; return list device status\r
73	?sctrn: jp sectrn ; translate logical to physical sector\r
74	\r
75	?conos: jp conost ; return console output status\r
76	?auxis: jp auxist ; return aux input status\r
77	?auxos: jp auxost ; return aux output status\r
78	?dvtbl: jp devtbl ; return address of device def table\r
79	?devin: jp cinit ; change baud rate of device\r
80	\r
81	?drtbl: jp getdrv ; return address of disk drive table\r
82	?mltio: jp multio ; set multiple record count for disk I/O\r
83	?flush: jp flush ; flush BIOS maintained disk caching\r
84	\r
85	?mov: jp move ; block move memory to memory\r
86	?tim: jp time ; Signal Time and Date operation\r
87	?bnksl: jp bnksel ; select bank for code execution and default DMA\r
88	?stbnk: jp setbnk ; select different bank for disk I/O DMA operations.\r
89	?xmov: jp xmove ; set source and destination banks for one operation\r
90	\r
91	jp 0 ; reserved for future expansion\r
92	jp 0 ; reserved for future expansion\r
93	jp 0 ; reserved for future expansion\r
94	\r
95	;----------------------------------------------------------------------\r
96	\r
97	hwini_tab:\r
98	db (hwini0_e-$)/2 ;count\r
99	db rcr,CREFSH ;configure DRAM refresh\r
100	db dcntl,CWAITIO ;wait states\r
101	db ccr,M_NCD ;No Clock Divide\r
102	db cmr,PHI_X2 ;X2 Clock Multiplier\r
103	db omcr,~M_IOC ;Operation Mode Control Register\r
104	;MMU\r
105	db cbr,SYS$CBR ;Common Base Register\r
106	db cbar,USR$CBAR ;Common Base Area Register\r
107	;ASCI0\r
108	db asext1,0 ;disable BRG\r
109	db stat1,00000000b ;disable RX, TX interrupt, disable CTS1\r
110	db cntlb1,10000000b;PS:10 DR:16 Rate:1 --> BR = Phi/160\r
111	db cntla1,01100101b;RE TE RTS:0 8N2\r
112	hwini0_e:\r
113	db 0 ;stop mark\r
114	db 0,0,0,0,0,0,0,0 ;\r
115	\r
116	msg_boot:\r
117	db cr,lf,'CPMLDR error: Unable to locate CP/M partition',cr,lf,0\r
118	\r
119	;-------------------------------------------------------------------------------\r
120	\r
121	; CP/M 3 Disk definition macros\r
122	\r
123	maclib cpm3slr.lib ; dpb mcaro\r
124	\r
125	; The dph macro from the lib depends on GENCPM\r
126	\r
127	dphldr macro ?trans,?dpb,?csize,?asize,?dirbcb,?dtabcb\r
128	local ?csv,?alv\r
129	dw ?trans ; translate table address\r
130	db 0,0,0,0,0,0,0,0,0 ; BDOS Scratch area\r
131	db 0 ; media flag\r
132	dw ?dpb ; disk parameter block\r
133	if nul ?csize\r
134	dw 0 ; permanently mounted, no checksum vector\r
135	else\r
136	if ?csize = 0\r
137	dw 0\r
138	else\r
139	dw ?csv ; checksum vector\r
140	endif\r
141	endif\r
142	if nul ?asize\r
143	dw 0 ; no alloc vector\r
144	else\r
145	if ?asize = 0\r
146	dw 0\r
147	else\r
148	dw ?alv ; allocation vector\r
149	endif\r
150	endif\r
151	dw ?dirbcb\r
152	dw ?dtabcb\r
153	dw 0ffffh ; no hash\r
154	db 0 ; hash bank\r
155	if not nul ?csize\r
156	if ?csize <> 0\r
157	?csv ds ?csize ; checksum vector\r
158	endif\r
159	endif\r
160	if not nul ?asize\r
161	if ?asize <> 0\r
162	?alv ds ?asize ; allocation vector\r
163	endif\r
164	endif\r
165	endm\r
166	\r
167	;-------------------------------------------------------------------------------\r
168	\r
169	; dphldr translate$table, - disk parameter header\r
170	; disk$parameter$block,\r
171	; checksum$size, (optional)\r
172	; alloc$size (optional)\r
173	; dir$bcb\r
174	; data$bcb\r
175	dph0:\r
176	dphldr 0,dpbsimhd512,0,0,bcb,bcb\r
177	\r
178	bcb:\r
179	db 0ffh\r
180	rept 9\r
181	db 0\r
182	endm\r
183	dw buffer\r
184	\r
185	; dpb physical$sector$size, - disk parameter block\r
186	; physical$sectors$per$track,\r
187	; number$tracks,\r
188	; block$size,\r
189	; number$dir$entries,\r
190	; track$offset,\r
191	; checksum$vec$size (optional)\r
192	\r
193	dpbsimhd512:\r
194	dpb 512,8,2048,4096,1024,6,8000h\r
195	\r
196	;-------------------------------------------------------------------------------\r
197	\r
198	wboot: ; jump vector locations not used\r
199	const:\r
200	conin:\r
201	list:\r
202	auxout:\r
203	auxin:\r
204	write:\r
205	listst:\r
206	conost:\r
207	auxist:\r
208	auxost:\r
209	devtbl:\r
210	cinit:\r
211	getdrv:\r
212	multio:\r
213	flush:\r
214	time:\r
215	bnksel:\r
216	setbnk:\r
217	xmove:\r
218	ret\r
219	\r
220	;-------------------------------------------------------------------------------\r
221	; output bytes to ports\r
222	;\r
223	; hl: tables of port,value pairs:\r
224	; db n, port1,val1, port2,val2,... portn,valn\r
225	; ...\r
226	; db 0 ; Terminate table\r
227	\r
228	ioini1l:\r
229	push bc\r
230	jr io1_nxt\r
231	io1_lp:\r
232	ld c,(hl) ;port address\r
233	inc hl\r
234	otim\r
235	jr nz,io1_lp\r
236	io1_nxt:\r
237	ld b,(hl) ;count\r
238	inc hl\r
239	inc b\r
240	djnz io1_lp\r
241	\r
242	pop bc\r
243	ret\r
244	\r
245	;-------------------------------------------------------------------------------\r
246	; print message @<HL> up to a null\r
247	\r
248	?pmsg:\r
249	ld a,(hl)\r
250	or a\r
251	ret z\r
252	ld c,a\r
253	push hl\r
254	call ?cono\r
255	pop hl\r
256	inc hl\r
257	jr ?pmsg\r
258	\r
259	;-------------------------------------------------------------------------------\r
260	\r
261	boot:\r
262	; Init CPU, MMU, ASCI0\r
263	\r
264	ld hl,hwini_tab\r
265	call ioini1l\r
266	\r
267	; Init disk partition\r
268	\r
269	call read_parttbl\r
270	or a\r
271	jr nz,boot_err\r
272	\r
273	; check_signature\r
274	\r
275	ld hl,buffer+512-1\r
276	ld a,0aah\r
277	cp (hl) ; Test, if it has a valid MBR\r
278	jr nz,boot_err\r
279	dec hl\r
280	cpl ; a=055h\r
281	cp (hl) ;\r
282	jr nz,boot_err\r
283	\r
284	; Find CP/M paartition\r
285	; Look for first CP/M partition and save partition offset\r
286	\r
287	ld hl,buffer+512-2-64+PART_TYPE ; Point to partition type of first first partition table entry\r
288	ld de,16\r
289	ld b,4 ; Max # of partition table entries\r
290	ploop:\r
291	ld a,PARTID_CPM\r
292	sub (HL) ; Test for CP/M Partition\r
293	jr nz,pnext\r
294	ld bc,4\r
295	add hl,bc ; Point to partition start (lba)\r
296	ld de,ptab_start\r
297	ldir\r
298	ret ;a=0\r
299	\r
300	pnext:\r
301	add hl,de\r
302	djnz ploop\r
303	\r
304	boot_err:\r
305	ld hl,msg_boot\r
306	call ?pmsg\r
307	halt_loop:\r
308	halt\r
309	jr halt_loop\r
310	\r
311	;-------------------------------------------------------------------------------\r
312	\r
313	conout:\r
314	in0 a,(stat1)\r
315	and M_TDRE\r
316	jr z,conout\r
317	out0 (tdr1),c\r
318	ld a,c\r
319	ret\r
320	\r
321	;-------------------------------------------------------------------------------\r
322	\r
323	move:\r
324	ex de,hl ; we are passed source in DE and dest in HL\r
325	ldir ; use Z80 block move instruction\r
326	ex de,hl ; need next addresses in same regs\r
327	ret\r
328	\r
329	;-------------------------------------------------------------------------------\r
330	; Select Disk Drive.\r
331	; Return address of disk parameter header in <HL>\r
332	\r
333	seldsk:\r
334	ld hl,dph0\r
335	ret\r
336	\r
337	; Home selected drive. Treated as SETTRK(0).\r
338	\r
339	home:\r
340	ld bc,0 ; same as set track zero\r
341	\r
342	; Set Track. Saves track address from <BC> in @trk.\r
343	\r
344	settrk:\r
345	ld (@trk),bc\r
346	ret\r
347	\r
348	; Set Sector. Saves sector number from <BC> in @sect.\r
349	\r
350	setsec:\r
351	ld (@sect),bc\r
352	ret\r
353	\r
354	; Set Disk Memory Address. Saves DMA address from <BC> in @dma.\r
355	\r
356	setdma:\r
357	ld (@dma),bc\r
358	ret\r
359	\r
360	; Translate sector address. Not needed. Return physical=logical.\r
361	\r
362	sectrn:\r
363	ld l,c\r
364	ld h,b\r
365	ret\r
366	\r
367	;-----------------------------------------------------------------\r
368	\r
369	chk_to:\r
370	xor a ;\r
371	to_l:\r
372	dec a\r
373	jr nz,to_l ;\r
374	dec hl ; 4\r
375	ld a,h ; 4\r
376	or l ; 4\r
377	ret nz ; 10/5\r
378	ccf ; 3\r
379	ret ; 9\r
380	\r
381	;-------------------------------------------------------------------------------\r
382	; Wait for ready signal with time out\r
383	; return:\r
384	; a = 0 if ok\r
385	; a = ff if timeout\r
386	\r
387	wait_rdy_to:\r
388	push hl\r
389	ld hl,TIMEOUT\r
390	wrdy_l:\r
391	in a,(IdeCmd)\r
392	xor 01000000b\r
393	and 11000000b ; clears carry\r
394	jr z,wrdy_e\r
395	call chk_to\r
396	jr nc,wrdy_l\r
397	wrdy_e:\r
398	pop hl\r
399	sbc a,a\r
400	ret\r
401	\r
402	\r
403	;-------------------------------------------------------------------------------\r
404	\r
405	do_ide_cmd:\r
406	out (IdeCmd),a ;\r
407	call wait_rdy_to\r
408	ret c\r
409	in a,(IdeCmd)\r
410	and 10001001b ;\r
411	ret\r
412	\r
413	\r
414	;-------------------------------------------------------------------------------\r
415	; Read partition table\r
416	\r
417	read_parttbl:\r
418	ld hl,ptab_start\r
419	ld b,8\r
420	rp_l:\r
421	ld (hl),0\r
422	inc hl\r
423	djnz rp_l\r
424	\r
425	ld hl,buffer\r
426	ld (@dma),hl\r
427	\r
428	; fall thru\r
429	\r
430	;-------------------------------------------------------------------------------\r
431	; Read a sector\r
432	\r
433	; compute logical block number (lba) --> cf-controller\r
434	\r
435	; TODO: sectors per track from dpb\r
436	; lba = track * 8 + sector\r
437	\r
438	read:\r
439	ld iy,ptab_start\r
440	xor a\r
441	ld hl,(@trk)\r
442	add hl,hl\r
443	adc a,a ; *2\r
444	add hl,hl\r
445	adc a,a ; *4\r
446	add hl,hl\r
447	adc a,a ; *8\r
448	ld de,(@sect)\r
449	add hl,de\r
450	adc a,0\r
451	ld e,a\r
452	call wait_rdy_to\r
453	ld a,(iy+0) ; add partition start\r
454	add a,l\r
455	out (IdeSNum),a\r
456	ld a,(iy+1)\r
457	adc a,h\r
458	out (IdeCLo),a\r
459	ld a,(iy+2)\r
460	adc a,e\r
461	out (IdeCHi),a\r
462	ld a,(iy+3)\r
463	adc a,0\r
464	and 00FH\r
465	or 0E0H\r
466	out (IdeSDH),a\r
467	ld hl,(@dma)\r
468	\r
469	ld a,1 ; number of sectors to read\r
470	out (IdeSCnt),a ; set sector count\r
471	\r
472	ld a,CmdRd\r
473	out (IdeCmd),a ; command: read sector data\r
474	ld bc,IdeDat ; I/O address\r
475	wdrq:\r
476	in a,(IdeCmd) ; wait for DRQ to become active\r
477	bit 3,a\r
478	jr z,wdrq\r
479	inir ; read 512 data bytes (2 x 256)\r
480	inir\r
481	wnb: ; wait while busy\r
482	in a,(IdeCmd) ;\r
483	rlca\r
484	jr c,wnb\r
485	rrca ; restore status\r
486	and 10001001b ; Busy, DRQ, or Error?\r
487	ret z ; return 0, if everything is ok\r
488	ld a,1\r
489	ret\r
490	\r
491	;-------------------------------------------------------------------------------\r
492	\r
493	ptab_start:\r
494	dw 0,0\r
495	@trk: dw 0\r
496	@sect: dw 0\r
497	@dma: dw 0\r
498	\r
499	buffer:\r
500	end\r