.xlist

;--------------------------------	
; AUTHOR  Marcus G. Calescibetta
; DATE    May 2, 1984
; VERSION 2.3
;--------------------------------

false		equ	0
true		equ	not false

;;---------------
;; DRIVE EQUATES
;;---------------
;;
;; high byte = no. of logical drives on physical drive
;; low  byte = physical drive type number (a unique no. identifing drive type)
;;

nodrive		equ	000fh		;; use to skip logigical drives

f548		equ	01f0h		;; 5.25" - 48 tpi floppy drive
f596		equ	01f1h		;; 5.25" - 96 tpi floppy drive
f8		equ	01f2h		;; 8" floppy drive

st503		equ	0100h		;; Seagate 503
st506		equ	0101h		;; Seagate 506
tm601s		equ	0102h		;; Tandon  601s
tm602s		equ	0103h		;; Tandon  602s
tm603s		equ	0104h		;; Tandon  603s
tm603se		equ	0205h		;; Tandon  603se
tm501		equ	0106h		;; Tandon  501
tm502		equ	0207h		;; Tandon  502
tm503		equ	0208h		;; Tandon  503
sa602		equ	0109h		;; Shugart 602
sa604		equ	010ah		;; Shugart 604
sa606		equ	010bh		;; Shugart 606
sa1002		equ	010ch		;; Shugart 1002
sa1004		equ	010dh		;; Shugart 1004
q2010		equ	010eh		;; Quantum 2010
q2020		equ	020fh		;; Quantum 2020
q2030		equ	0310h		;; Quantum 2030
q2040		equ	0411h		;; Quantum 2040
m4010		equ	0112h		;; Mini Scribe 4010
m4020		equ	0213h		;; Mini Scribe 4020
dma5		equ	0114h		;; DMA 5 removable
dma55c		equ	0215h		;; DMA 5/5 cartriage boot
dma55f		equ	0216h		;; DMA 5/5 fixed boot

maxhst		defl	0		;; maximum host sector size
maxusg		defl	0		;; maximum no. phy sec per block

frst8		defl	0ffffh		;; first 8" floppy drive flag
frst548		defl	0ffffh		;; first 5.25" 48 tpi floppy drive flag
frst596		defl	0ffffh		;; first 5.25" 96 tpi floppy drive flag

;;------------------------------------
;; MACRO - DISK PARAMETER DEFINITIONS
;;------------------------------------

dskdef	macro	drvstr

	.lall
;------------------
; SYSTEM DRIVE MAP 
;------------------
	.xall

hpdno	defl	0			;; hard disk physical drive no.
fpdno	defl	0			;; floppy disk physical drive no.
dno	defl	0			;; logical drv no. of our drvs
cnt	defl	0			;; cnt of how many entrys made

drvmap:
	irp	drvtyp,<drvstr>
	if	drvtyp lt 16
	xdmap	%drvtyp			;; enter previous drv into dmap
cnt	defl	cnt+1
	else
	if	drvtyp eq nodrive
	xxdmap				;; enter no drv entry into dmap
cnt	defl	cnt+1
	else

	if	(drvtyp eq f8) or (drvtyp eq f548) or (drvtyp eq f596)
	dmap	%dno,drvtyp,%fpdno
fpdno	defl	fpdno+1
dno	defl	dno+1
cnt	defl	cnt+1
	else

	repô	(drvtyð shò 8©		;» enteò logicaì drvó intï dmap
	dmap	%dno,drvtyp,%hpdno
dno	defl	dno+1
cnt	defl	cnt+1
	endm

hpdno	defl	hpdno+1
	endif

	endif
	endif
	endm

	rept	(010h-cnt)		;; fill in rest of drive map
	xxdmap
	endm

dno	defl	0
hpdno	defl	0
fpdno	defl	0

	irp	drvtyp,<drvstr>

;;--------------------------------
;; 5.25" 48-TPI FLOPPY DISK DRIVE
;;--------------------------------

	if	drvtyp eq f548

	dph	%dno,drvtyp

	if	frst548 eq 0ffffh

fdpb548:

;;-----------------------------------------------------
;; 	XEROX 820, KAYPRO II SINGLE DENSITY FORMAT
;;-----------------------------------------------------
;;
;;	dpb	10,18,3,7,0,82,31,8,3,1024
;;
;;-----------------------------------------------------
;; 	OSBORNE SINGLE DENSITY FORMAT
;;-----------------------------------------------------
;;
;;	dpb	10,20,4,15,1,45,63,16,3,2048
;;
;;-----------------------------------------------------

	dpb	10,20,4,15,1,45,63,16,3,2048
	dpb	11,32,4,15,0,77,63,32,1,2048
	dpb	12,64,4,15,0,155,127,32,1,2048

fddb548:

;;-----------------------------------------------------
;; XEROX 820, KAYPRO II SINGLE DENSITY FORMAT
;;-----------------------------------------------------
;;
;;	ddb	10,%fpdno,0,0,1024,128,64,1
;;
;;-----------------------------------------------------
;;	OSBORNE SINGLE DENSITY FORMAT
;;-----------------------------------------------------
;;
;;	ddb	10,%fpdno,0,0,2048,256,64,1
;;
;;-----------------------------------------------------


	ddb	10,%fpdno,0,0,2048,256,64,1
	ddb	11,%fpdno,0,0,2048,1024,4,1
	ddb	12,%fpdno,0,0,2048,1024,4,2

tran548:

;;-----------------------------------------------------
;; 	XEROX 820, KAYPRO II SINGLE DENSITY FORMAT
;;-----------------------------------------------------
;;
;;	db	1,6,11,16,3,8,13,18,5
;;	db	10,15,2,7,12,17,4,9,14
;;	ds	8,0ffh
;;
;;-----------------------------------------------------	
;;	OSBORNE SINGLE DENSITY FORMAT
;;-----------------------------------------------------
;;
;;	db	2,3,6,7,10,11,14,15,18,19
;;	db	4,5,8,9,12,13,16,17,20,21
;;	ds	6,0ffh
;;
;;-----------------------------------------------------

	db	2,3,6,7,10,11,14,15,18,19
	db	4,5,8,9,12,13,16,17,20,21
	ds	6,0ffh

frst548	defl	0
	endif

	alvcsv	%dno,155,32
dno	defl	dno+1

	endif

;;--------------------------------
;; 5.25" 96-TPI FLOPPY DISK DRIVE
;;--------------------------------

	if	drvtyp eq f596

	dph	%dno,drvtyp

	if	frst596 eq 0ffffh

fdpb596:
	dpb	20,18,3,7,0,82,63,16,3,1024
	dpb	21,32,4,15,0,150,63,32,1,2048
	dpb	22,64,4,15,0,300,127,32,1,2048
fddb596:
	ddb	20,%fpdno,0,0,1024,128,32,1
	ddb	21,%fpdno,0,0,2048,1024,4,1
	ddb	22,%fpdno,0,0,2048,1024,4,2
tran596:
	db	1,7,13,19,25,5,11,17,23,3,9,15,21
	db	2,8,14,20,26,6,12,18,24,4,10,16,22
	
frst596	defl	0
	endif

	alvcsv	%dno,300,32
dno	defl	dno+1

	endif

;;----------------------
;; 8" FLOPPY DISK DRIVE
;;----------------------

	if	drvtyp eq f8

	dph	%dno,drvtyp

	if	frst8 eq 0ffffh

fdpb8:
	dpb	30,26,3,7,0,242,63,16,2,1024
	dpb	31,64,4,15,0,303,127,32,1,2048
	dpb	32,128,4,15,0,607,255,32,1,2048
fddb8:
	ddb	30,%fpdno,0,0,1024,128,32,1
	ddb	31,%fpdno,0,0,2048,1024,8,1 
	ddb	32,%fpdno,0,0,2048,1024,8,2
tran8:
	db	1,7,13,19,25,5,11,17,23,3,9,15,21
	db	2,8,14,20,26,6,12,18,24,4,10,16,22
	
frst8	defl	0
	endif

	alvcsv	%dno,607,32
dno	defl	dno+1

	endif

;;-------------------------------------------
;; DMA MICRO MAGNUM 5/5 HARD DISK FIXED BOOT
;;-------------------------------------------

	if	drvtyp eq dma55f 
	dph	%dno
	dph	%dno+1
	dpb	%dno+0,128,5,31,1,1219,511,0,1,4096
	dpb	%dno+1,128,5,31,1,1219,511,0,1,4096
	ddb	%dno+0,%hpdno,2,15,4096,256,32,2
	ddb	%dno+1,%hpdno,0,15,4096,256,32,2
	alvcsv	%dno+0,1219,0
	alvcsv	%dno+1,1219,0
dno	defl	dno+2
	endif

;;-----------------------------------------------
;; DMA MICRO MAGNUM 5/5 HARD DISK CARTRIAGE BOOT
;;-----------------------------------------------

	if	drvtyp eq dma55c 
	dph	%dno
	dph	%dno+1
	dpb	%dno+0,128,5,31,1,1219,511,0,1,4096
	dpb	%dno+1,128,5,31,1,1219,511,0,1,4096
	ddb	%dno+0,%hpdno,0,15,4096,256,32,2
	ddb	%dno+1,%hpdno,2,15,4096,256,32,2
	alvcsv	%dno+0,1219,0
	alvcsv	%dno+1,1219,0
dno	defl	dno+2
	endif

;;------------------------------
;; DMA MICRO MAGNUM 5 HARD DISK
;;------------------------------

	if	drvtyp eq dma5 
	dph	%dno
	dpb	%dno+0,128,5,31,1,1219,511,0,1,4096
	ddb	%dno+0,%hpdno,0,15,4096,256,32,2
	alvcsv	%dno+0,1219,0
dno	defl	dno+1
	endif

;;------------------
;; ST 503 HARD DISK
;;------------------

	if	drvtyp eq st503 
	dph	%dno
	dpb	%dno+0,128,5,31,1,607,511,0,1,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,2
	alvcsv	%dno+0,607,0
dno	defl	dno+1
	endif	

;;------------------
;; ST 506 HARD DISK
;;------------------

	if	drvtyp eq st506
	dph	%dno
	dpb	%dno+0,256,5,31,1,1215,511,0,1,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,4
	alvcsv	%dno+0,1215,0
dno	defl	dno+1
	endif	

;;-------------------
;; TM 601S HARD DISK
;;-------------------

	if	drvtyp eq tm601S
	dph	%dno
	dpb	%dno+0,128,5,31,1,607,511,0,1,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,2
	alvcsv	%dno+0,607,0
dno	defl	dno+1
	endif	

;;-------------------
;; TM 602S HARD DISK
;;-------------------

	if	drvtyp eq tm602S
	dph	%dno
	dpb	%dno+0,256,5,31,1,1215,511,0,1,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,4
	alvcsv	%dno+0,1215,0
dno	defl	dno+1
	endif	

;;-------------------
;; TM 603S HARD DISK
;;-------------------

	if	drvtyp eq tm603S
	dph	%dno
	dpb	%dno+0,384,5,31,1,1823,1023,0,1,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,6
	alvcsv	%dno+0,1823,0
dno	defl	dno+1
	endif

;;--------------------
;; TM 603SE HARD DISK
;;--------------------

	if	drvtyp eq tm603SE
	dph	%dno
	dph	%dno+1
	dpb	%dno+0,384,5,31,1,2047,1023,0,1,4096
	dpb	%dno+1,384,5,31,1,699,511,0,172,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,6
	ddb	%dno+1,%hpdno,0,0,4096,512,16,6
	alvcsv	%dno+0,2047,0
	alvcsv	%dno+1,699,0
dno	defl	dno+2
	endif

;;------------------
;; TM 501 HARD DISK
;;------------------

	if	drvtyp eq tm501
	dph	%dno
	dpb	%dno+0,128,5,31,1,1219,511,0,1,4096
	ddb	%dno+0,%hpdno,0,3,4096,512,16,2
	alvcsv	%dno+0,1219,0
dno	defl	dno+1
	endif

;;------------------
;; TM 502 HARD DISK
;;------------------

	if	drvtyp eq tm502
	dph	%dno
	dph	%dno+1
	dpb	%dno+0,256,5,31,1,2047,1023,0,1,4096
	dpb	%dno+1,256,5,31,1,391,511,0,257,4096
	ddb	%dno+0,%hpdno,0,3,4096,512,16,4 
	ddb	%dno+1,%hpdno,0,3,4096,512,16,4
	alvcsv	%dno+0,2047,0
	alvcsv	%dno+1,391,0
dno	defl	dno+2
	endif

;;------------------
;; TM 503 HARD DISK
;;------------------

	if	drvtyp eq tm503
	dph	%dno
	dph	%dno+1
	dpb	%dno+0,384,5,31,1,2047,1023,0,1,4096
	dpb	%dno+1,384,5,31,1,1611,1023,0,172,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,6
	ddb	%dno+1,%hpdno,0,0,4096,512,16,6
	alvcsv	%dno+0,2047,0
	alvcsv	%dno+1,1611,0
dno	defl	dno+2
	endif

;;------------------
;; SA 602 HARD DISK
;;------------------

	if	drvtyp eq sa602
	dph	%dno
	dpb	%dno+0,128,5,31,1,635,511,0,1,4096
	ddb	%dno+0,%hpdno,0,3,4096,512,16,2
	alvcsv	%dno+0,635,0
dno	defl	dno+1
	endif

;;------------------
;; SA 604 HARD DISK
;;------------------

	if	drvtyp eq sa604
	dph	%dno
	dpb	%dno+0,256,5,31,1,1271,511,0,1,4096
	ddb	%dno+0,%hpdno,0,3,4096,512,16,4
	alvcsv	%dno+0,1271,0
dno	defl	dno+1
	endif

;;------------------
;; SA 606 HARD DISK
;;------------------

	if	drvtyp eq sa606
	dph	%dno
	dpb	%dno+0,384,5,31,1,1907,1023,0,1,4096
	ddb	%dno+0,%hpdno,0,3,4096,512,16,6
	alvcsv	%dno+0,1907,0
dno	defl	dno+1
	endif

;;-------------------
;; SA 1002 HARD DISK
;;-------------------

	if	drvtyp eq sa1002
	dph	%dno
	dpb	%dno+0,128,5,31,1,1019,511,0,1,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,2
	alvcsv	%dno+0,1019,0
dno	defl	dno+1
	endif

;;-------------------
;; SA 1004 HARD DISK
;;-------------------

	if	drvtyp eq sa1004
	dph	%dno
	dpb	%dno+0,256,5,31,1,2039,1023,0,1,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,4
	alvcsv	%dno+0,2039,0
dno	defl	dno+1
	endif

;;------------------------
;; QUANTUM 2010 HARD DISK
;;------------------------

	if	drvtyp eq q2010
	dph	%dno
	dpb	%dno+0,128,5,31,1,2043,1023,0,1,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,2
	alvcsv	%dno+0,2043,0
dno	defl	dno+1
	endif

;;------------------------
;; QUANTUM 2020 HARD DISK
;;------------------------

	if	drvtyp eq q2020
	dph	%dno
	dph	%dno+1

;;
;; Partion drive by track offset (use Q2020 loader)
;;	
;;	dpb	%dno+0,256,5,31,1,2047,1023,0,1,4096
;;	dpb	%dno+1,256,5,31,1,2039,1023,0,257,4096
;;	ddb	%dno+0,%hpdno,0,0,4096,512,16,4
;;	ddb	%dno+1,%hpdno,0,0,4096,512,16,4
;;	alvcsv	%dno+0,2047,0
;;	alvcsv	%dno+1,2039,0
;;
;; Partion drive by head offset (use Q2010 loader)
;;
;;	dpb	%dno+0,128,5,31,1,2043,1023,0,1,4096
;;	dpb	%dno+1,128,5,31,1,2043,1023,0,1,4096
;;	ddb	%dno+0,%hpdno,0,0,4096,512,16,2
;;	ddb	%dno+1,%hpdno,2,0,4096,512,16,2
;;	alvcsv	%dno+0,2043,0
;;	alvcsv	%dno+1,2043,0
;;

	dpb	%dno+0,256,5,31,1,2047,1023,0,1,4096
	dpb	%dno+1,256,5,31,1,2039,1023,0,257,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,4
	ddb	%dno+1,%hpdno,0,0,4096,512,16,4
	alvcsv	%dno+0,2047,0
	alvcsv	%dno+1,2039,0

dno	defl	dno+2
	endif

;;------------------------
;; QUANTUM 2030 HARD DISK
;;------------------------

	if	drvtyp eq q2030
	dph	%dno
	dph	%dno+1
	dph	%dno+2
	dpb	%dno+0,384,5,31,1,2047,1023,0,1,4096
	dpb	%dno+1,384,5,31,1,2047,1023,0,172,4096
	dpb	%dno+2,384,5,31,1,2031,1023,0,343,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,6
	ddb	%dno+1,%hpdno,0,0,4096,512,16,6
	ddb	%dno+2,%hpdno,0,0,4096,512,16,6
	alvcsv	%dno+0,2047,0
	alvcsv	%dno+1,2047,0
	alvcsv	%dno+2,2031,0
dno	defl	dno+3
	endif

;;------------------------
;; QUANTUM 2040 HARD DISK
;;------------------------

	if	drvtyp eq q2040
	dph	%dno
	dph	%dno+1
	dph	%dno+2
	dph	%dno+3
	dpb	%dno+0,512,5,31,1,2047,1023,0,1,4096
	dpb	%dno+1,512,5,31,1,2047,1023,0,129,4096
	dpb	%dno+2,512,5,31,1,2047,1023,0,257,4096
	dpb	%dno+3,512,5,31,1,2031,1023,0,385,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,8
	ddb	%dno+1,%hpdno,0,0,4096,512,16,8
	ddb	%dno+2,%hpdno,0,0,4096,512,16,8
	ddb	%dno+3,%hpdno,0,0,4096,512,16,8
	alvcsv	%dno+0,2047,0
	alvcsv	%dno+1,2047,0
	alvcsv	%dno+2,2047,0
	alvcsv	%dno+3,2031,0
dno	defl	dno+4
	endif

;;---------------------------
;; MINISCRIBE 4010 HARD DISK
;;---------------------------

	if	drvtyp eq m4010
	dph	%dno
	dpb	%dno+0,128,5,31,1,1915,1023,0,1,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,2
	alvcsv	%dno+0,1915,0
dno	defl	dno+1
	endif

;;---------------------------
;; MINISCRIBE 4020 HARD DISK
;;---------------------------

	if	drvtyp eq m4020
	dph	%dno
	dph	%dno+1
	dpb	%dno+0,256,5,31,1,2047,1023,0,1,4096
	dpb	%dno+1,256,5,31,1,1783,1023,0,257,4096
	ddb	%dno+0,%hpdno,0,0,4096,512,16,4
	ddb	%dno+1,%hpdno,0,0,4096,512,16,4
	alvcsv	%dno+0,2047,0
	alvcsv	%dno+1,1783,0
dno	defl	dno+2
	endif

	if	(drvtyp eq f8) or (drvtyp eq f548) or (drvtyp eq f596)
fpdno	defl	fpdno+1 	
	else
	if	drvtyp gt 15
hpdno	defl	hpdno+1
	endif
	endif

	endm

	if	frst8 eq 0ffffh
fdpb8:					; no 8" floppy used but need label
fddb8:					; no 8" floppy used but need label
tran8:					; no 8" floppy used but need label
	endif
	if	frst548 eq 0ffffh
fdpb548:				; no 5"-48 tpi drv used but need label
fddb548:				; no 5"-48 tpi drv used but need label
tran548:				; no 5"-48 tpi drv used but need label
	endif	
	if	frst596 eq 0ffffh
fdpb596:				; no 5"-96 tpi drv used but need label
fddb596:				; no 5"-96 tpi drv used but need label
tran596:				; no 5"=96 tpi drv used but need label
	endif

usgblk:	ds	maxusg			; maximum # host sectors / block
dirbuf:	ds	128d			; cp/m directory buffer storage 
hstbuf:					; host buffer follows 
	endm

;;-------------------
;; MACRO - DRIVE MAP 
;;-------------------

dmap	macro	dn,drvtyp,pdno

	if	drvtyp eq f548
	db	1,pdno			; 5" - 48 tpi floppy
	dw	dph&dn,ddb&10
	else
	if	drvtyp eq f596
	db	2,pdno			; 5" - 96 tpi floppy
	dw	dph&dn,ddb&20
	else
	if	drvtyp	eq f8
	db	3,pdno			; 8" floppy 
	dw	dph&dn,ddb&30
	else
	db	0,pdno			; hard disk
	dw	dph&dn,ddb&dn
	endif
	endif
	endif

	endm

xdmap	macro	dn
	db	010h,dn			; other bio's drive
	dw	0,0
	endm

xxdmap	macro	
	db	0ffh,0ffh		; no drive selected
	dw	0ffffh,0ffffh
	endm

;;---------------------------
;; MACRO - DISK HEADER BLOCK
;;---------------------------

dph	macro	dn,dtyp

	.lall
;-------------------
; DISK HEADER BLOCK
;-------------------
	.xall	
dph&dn:
	dw	0000			; translation vector
	dw	0000			; scratch pad 1
	dw	0000			; scratch pad 2
	dw	0000			; scratch pad 3
	dw	dirbuf			; dirbuf addr 

	ifb	<dtyp> 
	dw	dpb&dn			; dpb addr for hrd dsk
	else
	dw	0			; dpb addr for fpy filled in dynamicly
	endif

	dw	csv&dn			; directory check vector
	dw	alv&dn			; disk allocation vector

	endm

;;------------------------------
;; MACRO - DISK PARAMETER BLOCK
;;------------------------------

dpb	macro 	dn,spt,bsh,blm,exm,dsm,drm,cks,off,bsiz

	.lall
;----------------------
; DISK PARAMETER BLOCK
;----------------------
	.xall

dpb&dn:
	dw	spt			; cpm sectors per track
	db	bsh			; block shift factor
	db	blm			; block mask
	db	exm			; extent mask
	dw	dsm			; no. blocks on drive
	dw	drm			; no. directory entrys
	rsvdir	dn,drm,bsiz		;;reserved directory blocks 
	dw	cks			; no. directory entries to check
	dw	off			; track offset

	endm
	
;;-------------------------------
;; MACRO - DISK DEBLOCKING BLOCK
;;-------------------------------

ddb	macro	dn,pd,hdoff,srate,bsiz,hsiz,hsspt,hhd

	.lall
;-----------------------
; DISK DEBLOCKING BLOCK
;-----------------------
	.xall

ddb&dn:
	dw	hsiz			; host sec size
	ssiz	hsiz			;;sdh register sector size
	db	pd			; physical drive no.
	db	hdoff			; head offset (for partioning by hds)
	db	srate			; cmd register step rate
	db	hsspt-1			; host sec per trk - 1 (hst sec msk)
	db	(bsiz/hsiz)-1		; host sec per blk - 1 (blk sec msk)
	shff	((hsiz/128)*hsspt)	;;calc log2 cpm spt 
	shff	(bsiz/128)		;;calc log2 cpm spb
	db	hhd-1			; heads - 1
	shff	(hsiz/128)		;;calc log2 cpm sps
	db	(hsiz/128)-1 		; cpm sps - 1

	if	hsiz gt maxhst
maxhst	defl	hsiz
	endif

	if	(bsiz/hsiz) gt maxusg
maxusg	defl	(bsiz/hsiz)
	endif

	endm

;;--------------------------------------
;; MACRO - COMPUTE ALV AND CSV BUF SIZE
;;--------------------------------------


alvcsv	macro	dn,dsm,cks

	.lall
;---------------------------------------
; DRIVE ALLOCATION AND CHECK SUM VECTOR
;---------------------------------------
	.xall

alv&dn:	ds	(dsm/8)+1		; drive block allocation vector
csv&dn:	ds	cks			; drive directory check vector

	endm

;;--------------------------------------
;; MACRO - COMPUTE NO. DIRECTORY BLOCKS
;;--------------------------------------

rsvdir	macro	dn,drm,bsiz

x	defl	((drm+1)/(bsiz/32))
y	defl	080h
done	defl	0
al0&dn	defl	0
al1&dn	defl	0

	rept	8
	if	x eq 0
	db	al0&dn			; directory block allocation 0
	db	al1&dn			; directory block allocation 1
done	defl	0ffh
	exitm
	endif

al0&dn	defl	al0&dn or y
y	defl	y shr 1
x	defl	x-1
	endm

y	defl	080h

	if	done eq 0
	rept	8
	if	x eq 0
	db	al0&dn			; directory block allocation 0
	db	al1&dn			; directory block allocation 1
done	defl	0ffh
	exitm
	endif

al1&dn	defl	al1&dn or y
y	defl	y shr 1
x	defl	x-1
	endm
	endif

	if	done eq 0
	db	al0&dn			; directory block allocation 0
	db	al1&dn			; directory block allocation 1
	endif

	endm
	
;;-----------------------------------
;; MACRO - COMPUTE DRIVE SECTOR SIZE
;;-----------------------------------

ssiz	macro	secsiz

	if	secsiz eq 128
	db	060h			; sdh reg sec siz 060 = 128 bps
	else

	if	secsiz eq 512
	db	020h			; sdh reg sec siz 020 = 512 bps
	else

	if	secsiz eq 256
	db	000h			; sdh reg sec siz 000 = 256 bps
	else

	db	000h

	endif
	endif
	endif


	endm

;;------------------------------
;; MACRO - COMPUTE SHIFT FACTOR
;;------------------------------

shff	macro	num			 

@y	defl	num
@x	defl	0

	rept	8
	if	@y eq 1
	db	@x			; log2 (num)
	exitm
	endif
@y	defl	@y shr 1
@x	defl	@x + 1
	endm

	endm

	.list