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SUBTTL Initialized data and data used at DOS initialization
PAGE
; DATA AREA for MS-DOS
IFNDEF KANJI
KANJI EQU 0 ;FALSE
ENDIF
CONSTANTS SEGMENT BYTE PUBLIC 'CONST'
EXTRN international_table:BYTE
EXTRN Current_Country:WORD
ORG 0
CONSTRT EQU $ ; Start of constants segment
PUBLIC DevStrLen
DEVSTRLEN DB 3 ; Size of below
PUBLIC DevString
DEVSTRING DB "DEV" ; Dummy device directory
;
; Table of routines for assignable devices
;
; MSDOS allows assignment if the following standard devices:
; stdin (usually CON input)
; stdout (usually CON output)
; auxin (usually AUX input)
; auxout (usually AUX output)
; stdlpt (usually PRN output)
;
; SPECIAL NOTE:
; Status of a file is a strange idea. We choose to handle it in this manner:
; If we're not at end-of-file, then we always say that we have a character.
; Otherwise, we return ^Z as the character and set the ZERO flag. In this
; manner we can support program written under the old DOS (they use ^Z as EOF
; on devices) and programs written under the new DOS (they use the ZERO flag
; as EOF).
; Default FCBs for boot up
sftabl LABEL DWORD ; file table
DW -1
DW -1
DW sf_default_number ; Number of entries in table
DB sf_default_number DUP ( (SIZE sf_entry) DUP (0))
I_AM NoSetDir,BYTE ; true -> do not set directory
I_am DidCTRLC,BYTE ; true -> we did a ^C exit
I_am SpaceFlag,BYTE ; true -> embedded spaces are allowed
; in FCB
; the next two variables relate to the position of the logical stdout/stdin
; cursor. They are only meaningful when stdin/stdout are assigned to the
; console.
i_am CARPOS,BYTE ; cursor position in stdin
i_am STARTPOS,BYTE ; position of cursor at beginning
; of buffered input call
I_AM PFLAG,BYTE
I_AM VERFLG,BYTE ; Initialize with verify off
I_AM CONTPOS,WORD
PUBLIC CHARCO
CHARCO DB 00000011B ; Allows statchks every 4 chars...
I_AM DMAADD,DWORD ; User's disk transfer address
; (disp/seg)
ORG $-CONSTRT-4
DW 80H
DW ?
ENDMEM DW ?
PUBLIC switch_character
switch_character DB '/'
PUBLIC device_availability
device_availability DB 0FFH
I_AM FirstArena,WORD ; first free block found
I_AM BestArena,WORD ; best free block found
I_AM LastArena,WORD ; last free block found
I_AM AllocMethod,BYTE ; how to alloc first(best)last
I_AM arena_head,WORD
; The following block of data is used by SYSINIT. Do not change the order or
; size of this block
PUBLIC SYSINITVAR
SYSINITVAR LABEL WORD
I_AM DPBHEAD,DWORD ; Pointer to head of DPB-FAT list
I_AM sft_addr,DWORD ; Pointer to first FCB table
ORG $-CONSTRT-4
short_addr sftabl
DW ? ; DOS segment set at INIT
; The following address points to the CLOCK device
i_am BCLOCK,DWORD
; The following address is used by DISKSTATCHK it is always points to the
; console input device header
I_AM BCON,DWORD ; Console device entry points
i_am NUMIO,BYTE ; Number of disk tables
MAXSEC DW 0 ; Maximum allowed sector size
I_AM BUFFHEAD,DWORD ; Pointer to head of buffer queue
DEVHEAD LABEL DWORD
I_AM NULDEV,DWORD ; Set to list start passed by
; BIOS at DOS Init
DW DEVTYP OR ISNULL
short_addr SNULDEV
short_addr INULDEV
DB "NUL "
i_am DAY,BYTE
i_am MONTH,BYTE
i_am YEAR,WORD
i_am DAYCNT,WORD
i_am WEEKDAY,BYTE
ORG $-CONSTRT-7
DB 0,0
DW 0,-1
DB 0
I_AM CURDRV,BYTE ; Default to drive A
I_AM LASTENT,WORD
i_am INDOS,BYTE ; DOS status for interrupt processing
ORG $-CONSTRT-1
DB 0
I_AM ErrorMode,BYTE ; Flag for INT 24 processing
PUBLIC WPErr
WPERR DB -1 ; Write protect error flag
I_AM CONSWAP,BYTE
PUBLIC IDLEINT
IDLEINT DB 1
PUBLIC CNTCFLAG
CNTCFLAG DB 0 ; ^C check in dispatch disabled
PUBLIC LastBuffer
LASTBUFFER LABEL DWORD ; Buffer queue recency pointer
DW -1
DW -1
; Combination of all device call parameters
PUBLIC DEVCALL
DEVCALL SRHEAD <>
CALLUNIT LABEL BYTE
CALLFLSH LABEL WORD
I_AM CALLMED,BYTE
CALLBR LABEL DWORD
PUBLIC CALLXAD
CALLXAD LABEL DWORD
I_AM CALLRBYT,BYTE
DB 3 DUP(?)
PUBLIC CallBPB
CALLBPB LABEL DWORD
I_AM CALLSCNT,WORD
CALLSSEC DW ?
I_AM CALLDEVAD,DWORD ; stash for device entry point
; Same as above for I/O calls
PUBLIC IOCall
IOCALL SRHEAD <>
IOFLSH LABEL WORD
PUBLIC IORCHR
IORCHR LABEL BYTE
I_AM IOMED,BYTE
I_AM IOXAD,DWORD
I_AM IOSCNT,WORD
I_AM IOSSEC,WORD
; Call struct for DSKSTATCHK
PUBLIC DSKSTCALL
DSKSTCALL DB DRDNDHL
DB 0
PUBLIC DSKSTCOM
DSKSTCOM DB DEVRDND
I_AM DSKSTST,WORD
DB 8 DUP (0)
I_AM DSKCHRET,BYTE
short_addr DEVIOBUF
DW ? ; DOS segment set at Init
PUBLIC DSKSTCNT
DSKSTCNT DW 1
DW 0
; Days in year
i_am YRTAB,8
ORG $-CONSTRT-8
DB 200,166 ; Leap year
DB 200,165
DB 200,165
DB 200,165
; Days of each month
i_am MONTAB,12
ORG $-CONSTRT-12
DB 31 ; January
DB 28 ; February--reset each
; time year changes
DB 31 ; March
DB 30 ; April
DB 31 ; May
DB 30 ; June
DB 31 ; July
DB 31 ; August
DB 30 ; September
DB 31 ; October
DB 30 ; November
DB 31 ; December
IF NOT IBM
PUBLIC OEM_HANDLER
OEM_HANDLER DD -1
ENDIF
;WARNING For HIGHMEM version, these two vars must be at the end of the
; Constants segment to prevent them getting overwritten.
I_AM CurrentPDB,WORD
i_am CreatePDB,BYTE ; flag for creating a process
PUBLIC LEAVEADDR
LEAVEADDR LABEL WORD
short_addr LEAVE
CONSTANTS ENDS
SUBTTL Uninitialized data overlayed by initialization code
PAGE
DATA SEGMENT WORD PUBLIC 'DATA'
; Init code overlaps with data area below
ORG 0
i_am INBUF,128
I_AM CONBUF,131 ; The rest of INBUF and console buffer
i_am TIMEBUF,6
I_AM DEVIOBUF,2 ; Buffer for I/O under file assignment
I_AM EXITHOLD,DWORD
PUBLIC DevFCB
DEVFCB LABEL BYTE ; Uses NAME1, NAME2, NAME3 combined
; WARNING.. do not alter size or relative location of the following 4 items
; without first examining FCB_RENAME
I_AM NAME1,12 ; File name buffer
I_AM ATTRIB,BYTE
I_AM NAME2,13
I_AM NAME3,14
I_AM EXTFCB,BYTE
; WARNING - the following two items are accessed as a word
I_AM CREATING,BYTE
I_AM DELALL,BYTE
I_AM FoundDel,BYTE
I_AM user_SP,WORD
I_AM user_SS,WORD
I_AM CONTSTK,WORD
I_AM SECCLUSPOS,BYTE ; Position of first sector
; within cluster
I_AM DSKERR,BYTE
I_AM TRANS,BYTE
I_AM READOP,BYTE
I_AM THISDRV,BYTE
I_AM THISDPB,DWORD
I_AM CLUSFAC,BYTE
; WARNING - the following two items are accessed as a word
I_AM DRIVESPEC,BYTE
I_AM ROOTSTART,BYTE
I_AM CLUSSPLIT,BYTE
i_am INSMODE,BYTE
I_AM CLUSSAVE,WORD
I_AM CLUSSEC,WORD
I_AM PREREAD,WORD ; 0 means preread; 1 means optional
I_AM FATBYT,WORD
I_AM DEVPT,DWORD
I_AM THISFCB,DWORD ; Address of user FCB
I_AM NEXTADD,WORD
I_AM RECPOS,4
I_AM RECCNT,WORD
I_AM LASTPOS,WORD
I_AM CLUSNUM,WORD
I_AM DIRSEC,WORD
I_AM DIRSTART,WORD
I_AM SECPOS,WORD ; Position of first sector accessed
I_AM VALSEC,WORD ; Number of valid (previously written)
; sectors
I_AM BYTSECPOS,WORD ; Position of first byte within sector
I_AM BYTPOS,4 ; Byte position in file of access
I_AM BYTCNT1,WORD ; No. of bytes in first sector
I_AM BYTCNT2,WORD ; No. of bytes in last sector
I_AM SECCNT,WORD ; No. of whole sectors
I_AM ENTFREE,WORD
I_AM ENTLAST,WORD
I_AM NXTCLUSNUM,WORD
I_AM GROWCNT,DWORD
I_AM CURBUF,DWORD
I_AM VOLID,BYTE
I_AM NULLDEVPT,DWORD
I_AM CINSAV,DWORD
I_AM CINDSAV,BYTE
I_AM COUTDSAV,BYTE
I_AM COUTSAV,DWORD
PUBLIC SaveBX
SaveBX DW ?
PUBLIC SaveDS
SaveDS DW ?
I_AM ConC_spsave,WORD
I_AM exit_code,WORD ; exit code of last proc.
I_am exit_type,BYTE ; type of exit...
IF IBM
;For 2.00 this pads the DOS so that on a 2 disk IBM PC with no
;CONFIG.SYS file the space taken up by BIOS, DOS, res COMMAND is
;about 24K
IBMPAD DB 540h DUP(?)
ENDIF
; make those pushes fast!!!
EVEN
DB 0A0H DUP (?)
I_am AuxStack,0A0h
I_AM DSKSTACK,0A0h ; Stack space
PUBLIC IOSTACK
IOSTACK LABEL BYTE
PUBLIC NSS
NSS DW ?
PUBLIC NSP
NSP DW ?
PAGE
INCLUDE MSINIT.ASM
|
