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SYSINIT.ASM
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TITLE BIOS SYSTEM INITIALIZATION
FALSE EQU 0
TRUE EQU NOT FALSE
IBMVER EQU FALSE
IBM EQU IBMVER
IBMJAPVER EQU FALSE ; If TRUE set KANJI true also
MSVER EQU TRUE
ALTVECT EQU FALSE ; Switch to build ALTVECT version
HIGHMEM EQU FALSE
KANJI EQU FALSE
IF IBMVER OR IBMJAPVER
NOEXEC EQU TRUE
ELSE
NOEXEC EQU FALSE
ENDIF
; Set to agree with those in DOST:MSHEAD.ASM, ALTVECT version only
MAJOR_VERSION EQU 2
MINOR_VERSION EQU 0B ;2.11
DOSSIZE EQU 5000H
; Internal DOS data returned by DOSINIT
SYSINITVAR STRUC
DPBHEAD DD ? ; Pointer to head of DPB-FAT list
sft_addr DD ? ; Pointer to first FCB table
; The following address points to the CLOCK device
BCLOCK DD ?
; The following address is used by DISKSTATCHK it is always
; points to the console input device header
BCON DD ? ; Console device entry points
NUMIO DB 0 ; Number of disk tables
MAXSEC DW 0 ; Maximum allowed sector size
BUFFHEAD DD ? ; Head of buffer queue
DEVHEAD DD ?
SYSINITVAR ENDS
INCLUDE DOSSYM.ASM
INCLUDE DEVSYM.ASM
IF NOT IBM
IF NOT IBMJAPVER
EXTRN RE_INIT:FAR
ENDIF
ENDIF
SYSINITSEG SEGMENT PUBLIC 'SYSTEM_INIT'
ASSUME CS:SYSINITSEG,DS:NOTHING,ES:NOTHING,SS:NOTHING
EXTRN BADOPM:BYTE,CRLFM:BYTE,BADCOM:BYTE
EXTRN SYSSIZE:BYTE
;Strategy pointer save.
PUBLIC CURRENT_DOS_LOCATION
PUBLIC FINAL_DOS_LOCATION
PUBLIC DEVICE_LIST
PUBLIC MEMORY_SIZE
PUBLIC DEFAULT_DRIVE
PUBLIC BUFFERS
PUBLIC FILES
PUBLIC SYSINIT
IF HIGHMEM
PUBLIC DPBBUF_SIZ
ENDIF
SYSINIT:
JMP GOINIT
BADCOUNTRY DB 0
BADLD_POST DB 0
BADSIZ_POST DB 0
BADLD_PRE DB 0
BADSIZ_PRE DB 0
DOSINFO LABEL DWORD
DW 0000
CURRENT_DOS_LOCATION DW 0000
MSDOS LABEL DWORD
ENTRY_POINT LABEL DWORD
DW 0000
FINAL_DOS_LOCATION DW 0000
DEVICE_LIST DD 00000000
IF HIGHMEM
DPBBUF_SIZ DW (4472 + 15) / 16
ENDIF
MEMORY_SIZE DW 0001
DEFAULT_DRIVE DB 00
BUFFERS DB 2
FILES DB 8
COMMAND_LINE DB 2,0,"P" ; Default Command.com Args
DB 29 DUP (0)
ZERO DB 0
IF NOT NOEXEC
COMEXE EXEC0 <0,COMMAND_LINE,DEFAULT_DRIVE,ZERO>
ENDIF
COUNT DW 0000
CHRPTR DW 0000
BUFPTR LABEL DWORD ; LEAVE THIS STUFF IN ORDER!
MEMLO DW 0
PRMBLK LABEL WORD
MEMHI DW 0
LDOFF DW 0
AREA DW 0
PACKET DB 22
DB 0
DB 0 ; INITIALIZE CODE
DW 0
DB 8 DUP (?)
UNITCOUNT DB 0
BREAK_ADDR DD 0
BPB_ADDR DD 0
GOINIT:
CLD
XOR SI,SI
MOV DI,SI
IF MSVER
MOV CX,[MEMORY_SIZE]
CMP CX,1
JNZ NOSCAN
MOV CX,2048 ; START SCANNING AT 32K BOUNDARY
XOR BX,BX
MEMSCAN:INC CX
JZ SETEND
MOV DS,CX
MOV AL,[BX]
NOT AL
MOV [BX],AL
CMP AL,[BX]
NOT AL
MOV [BX],AL
JZ MEMSCAN
SETEND:
MOV [MEMORY_SIZE],CX
ENDIF
IF IBMVER OR IBMJAPVER
MOV CX,[MEMORY_SIZE]
ENDIF
NOSCAN:
MOV AX,CS
MOV DS,AX
ASSUME DS:SYSINITSEG
IF HIGHMEM
SUB CX,(DOSSIZE / 16) ; Leave room for DOS
SUB CX,CS:[DPBBUF_SIZ] ; Allow OEM to tune
ENDIF
MOV AX,OFFSET SYSSIZE + 15
SHR AX,1 ; Divide by 16 for paras
SHR AX,1
SHR AX,1
SHR AX,1
SUB CX,AX
MOV ES,CX
MOV CX,OFFSET SYSSIZE + 1
SHR CX,1 ; Divide by 2 to get words
REP MOVSW ; RELOCATE SYSINIT
ASSUME ES:SYSINITSEG
PUSH ES
MOV AX,OFFSET SYSIN
PUSH AX
AAA PROC FAR
RET
AAA ENDP
;
; MOVE THE DOS TO ITS PROPER LOCATION
;
SYSIN:
ASSUME DS:NOTHING,ES:SYSINITSEG,SS:NOTHING
MOV AX,[CURRENT_DOS_LOCATION]
MOV DS,AX
MOV AX,[FINAL_DOS_LOCATION]
MOV ES,AX
ASSUME ES:NOTHING
XOR SI,SI
MOV DI,SI
MOV CX,DOSSIZE/2
REP MOVSW
LDS SI,[DEVICE_LIST]
MOV DX,[MEMORY_SIZE]
CLI
MOV AX,CS
MOV SS,AX
MOV SP,OFFSET LOCSTACK
ASSUME SS:SYSINITSEG
IF NOT ALTVECT
STI ; Leave INTs disabled for ALTVECT
ENDIF
LOCSTACK LABEL BYTE
CALL MSDOS
MOV WORD PTR [DOSINFO+2],ES ; SAVE POINTER TO DOS INFO
MOV WORD PTR [DOSINFO],DI
IF NOT IBM
IF NOT IBMJAPVER
CALL RE_INIT ; Re-call the BIOS
ENDIF
ENDIF
STI
CLD
IF HIGHMEM
PUSH DS
MOV BX,DS
ADD BX,10H
MOV ES,BX
PUSH CS
POP DS
XOR SI,SI
MOV DI,SI
MOV CX,OFFSET SYSSIZE + 1
SHR CX,1 ; Divide by 2 to get words
REP MOVSW
POP DS
PUSH ES
MOV AX,OFFSET SECONDRELOC
PUSH AX
BBB PROC FAR
RET
BBB ENDP
SECONDRELOC:
MOV AX,CS
CLI
MOV SS,AX
MOV SP,OFFSET LOCSTACK
STI
ELSE
MOV BX,CS
SUB BX,10H
MOV ES,BX
XOR SI,SI
MOV DI,SI
MOV CX,80H
REP MOVSW
MOV AH,SET_CURRENT_PDB
INT 21H
ENDIF
PUSH DS
PUSH CS
POP DS
MOV DX,OFFSET INT24 ; SET UP INT 24 HANDLER
MOV AX,(SET_INTERRUPT_VECTOR SHL 8) OR 24H
INT 21H
IF ALTVECT
MOV DX,OFFSET BOOTMES
CALL PRINT ; Print message DOSINIT couldn't
ENDIF
POP DS
MOV DL,[DEFAULT_DRIVE]
OR DL,DL
JZ NODRVSET
DEC DL ; A = 0
MOV AH,SET_DEFAULT_DRIVE
INT 21H ; SELECT THE DISK
NODRVSET:
CALL DOCONF ; DO THE CONFIG STUFF
IF HIGHMEM
PUSH DS
MOV AX,OFFSET SYSSIZE + 15
MOV CL,4
SHR AX,CL ; Divide by 16 to get para
MOV CX,ES
SUB CX,AX
MOV ES,CX
PUSH CS
POP DS
XOR SI,SI
MOV DI,SI
MOV CX,OFFSET SYSSIZE + 1
SHR CX,1 ; Divide by 2 to get words
REP MOVSW
POP DS
PUSH ES
MOV AX,OFFSET THIRDRELOC
PUSH AX
CCC PROC FAR
RET
CCC ENDP
THIRDRELOC:
MOV AX,CS
CLI
MOV SS,AX
MOV SP,OFFSET LOCSTACK
STI
ENDIF
IF NOEXEC
MOV BP,DS ; SAVE COMMAND.COM SEGMENT
PUSH DS
POP ES
MOV BX,CS
SUB BX,10H
MOV DS,BX
XOR SI,SI
MOV DI,SI
MOV CX,80H
REP MOVSW
MOV BX,ES
MOV AH,SET_CURRENT_PDB
INT 21H
MOV ES:[PDB_PARENT_PID],ES ; WE ARE THE ROOT
ENDIF
PUSH CS
POP DS
ASSUME DS:SYSINITSEG
MOV AL,[FILES]
CBW
MOV CX,AX
XOR BX,BX ; Close standard input
MOV AH,CLOSE
INT 21H
MOV BX,2
RCCLLOOP: ; Close everybody but standard output
MOV AH,CLOSE
INT 21H
INC BX
LOOP RCCLLOOP
MOV DX,OFFSET CONDEV
mov al,1
out 03H,al
MOV AL,2
MOV AH,OPEN ; OPEN CON FOR READ/WRITE
STC
INT 21H
JNC GOAUX
CALL BADFIL
JMP SHORT GOAUX2
GOAUX: PUSH AX
MOV BX,1 ; close standard output
mov al,2
out 03h,al
MOV AH,CLOSE
INT 21H
POP AX
MOV BX,AX ; New device handle
MOV AH,XDUP
INT 21H ; Dup to 1, STDOUT
MOV AH,XDUP
INT 21H ; Dup to 2, STDERR
GOAUX2: MOV DX,OFFSET AUXDEV
MOV AL,3
OUT 03H,AL
MOV AL,2 ; READ/WRITE ACCESS
CALL OPEN_DEV
MOV DX,OFFSET PRNDEV
MOV AL,1 ; WRITE ONLY
CALL OPEN_DEV
;
; SET UP THE PARAMETERS FOR COMMAND
;
GOSET:
MOV SI,OFFSET COMMAND_LINE+1
IF NOEXEC
MOV DI,81H
ELSE
PUSH DS
POP ES
MOV DI,SI
ENDIF
MOV CL,-1
COMTRANLP: ; FIND LENGTH OF COMMAND LINE
INC CL
LODSB
STOSB ; COPY COMMAND LINE IN
OR AL,AL
JNZ COMTRANLP
DEC DI
MOV AL,0DH
STOSB
IF NOEXEC
MOV ES:[80H],CL
MOV AL,[DEFAULT_DRIVE]
MOV ES:[5CH],AL
ELSE
MOV [COMMAND_LINE],CL ; Count
ENDIF
PUSH CS
POP ES
ASSUME ES:SYSINITSEG
MOV DX,OFFSET COMMND ; NOW POINTING TO FILE DESCRIPTION
IF NOEXEC
MOV ES,BP ; SET LOAD ADDRESS
MOV BX,100H
CALL LDFIL ; READ IN COMMAND
JC COMERR
MOV DS,BP
CLI
MOV DX,80H
MOV SS,BP
MOV SP,DX
STI
XOR AX,AX ; PUSH A WORD OF ZEROS
PUSH AX
MOV AH,SET_DMA ; SET DISK TRANFER ADDRESS
INT 21H
PUSH BP ; SET HIGH PART OF JUMP ADDRESS
MOV AX,100H
PUSH AX ; SET LOW PART OF JUMP ADDRESS
CCC PROC FAR
RET ; CRANK UP COMMAND!
CCC ENDP
ELSE
PUSH AX
MOV AL,5
OUT 03H, AL
POP AX
MOV BX,OFFSET COMEXE
MOV WORD PTR [BX.EXEC0_COM_LINE+2],CS
MOV WORD PTR [BX.EXEC0_5C_FCB+2],CS
MOV WORD PTR [BX.EXEC0_6C_FCB+2],CS
XOR AX,AX
MOV AH,EXEC
STC ; IN CASE OF INT 24
INT 21H ; GO START UP COMMAND
ENDIF
COMERR:
MOV DX,OFFSET BADCOM ; WANT TO PRINT COMMAND ERROR
CALL BADFIL
STALL: JMP STALL
DOCONF:
PUSH CS
POP DS
ASSUME DS:SYSINITSEG
MOV BX,0FFFFH
MOV AH,ALLOC
INT 21H ; FIRST TIME FAILS
MOV AH,ALLOC
INT 21H ; SECOND TIME GETS IT
MOV [AREA],AX
IF HIGHMEM
ADD AX,BX
ENDIF
MOV [MEMHI],AX
MOV AX,(CHAR_OPER SHL 8) ; GET SWITCH CHARACTER
INT 21H
MOV [COMMAND_LINE+1],DL
MOV DX,OFFSET CONFIG ; NOW POINTING TO FILE DESCRIPTION
MOV AX,OPEN SHL 8 ; OPEN FILE "CONFIG.SYS"
STC ; IN CASE OF INT 24
INT 21H ; FUNCTION REQUEST
JC ENDFILE
JMP NOPROB ; PROBLEM WITH OPEN
ENDFILE:
PUSH CS
POP DS
CALL ROUND
MOV AL,[FILES]
SUB AL,5
JBE DOBUFF
CBW
IF HIGHMEM
PUSH AX
MOV BL,SIZE SF_ENTRY
MUL BL
ADD AX,15+6
MOV CL,4
SHR AX,CL
SUB [MEMHI],AX
POP AX
ENDIF
MOV BX,[MEMLO]
MOV DX,[MEMHI]
LDS DI,[DOSINFO] ; GET POINTER TO DOS DATA
LDS DI,[DI+SFT_ADDR] ; DS:BP POINTS TO SFT
MOV WORD PTR [DI+SFT_LINK],BX
MOV WORD PTR [DI+SFT_LINK+2],DX ; SET POINTER TO NEW SFT
PUSH CS
POP DS
LES DI,DWORD PTR [MEMLO] ; POINT TO NEW SFT
MOV WORD PTR ES:[DI+SFT_LINK],-1
MOV ES:[DI+SFT_COUNT],AX
MOV BL,SIZE SF_ENTRY
MUL BL ; AX = NUMBER OF BYTES TO CLEAR
MOV CX,AX
IF HIGHMEM
MOV AX,6
ELSE
ADD [MEMLO],AX ; ALLOCATE MEMORY
MOV AX,6
ADD [MEMLO],AX ; REMEMBER THE HEADER TOO
ENDIF
ADD DI,AX
XOR AX,AX
REP STOSB ; CLEAN OUT THE STUFF
DOBUFF: CALL ROUND
DEC [BUFFERS]
JZ BUF1
PUSH DS
LES DI,BUFPTR
LDS BX,DOSINFO
IF HIGHMEM
MOV AX,[BX.MAXSEC]
ADD AX,BUFINSIZ + 15
MOV CL,4
SHR AX,CL
SUB CS:[MEMHI],AX
MOV ES,CS:[MEMHI]
ENDIF
MOV AX,WORD PTR [BX.BUFFHEAD]
MOV WORD PTR ES:[DI.NEXTBUF],AX
MOV AX,WORD PTR [BX.BUFFHEAD+2]
MOV WORD PTR ES:[DI.NEXTBUF+2],AX
MOV WORD PTR [BX.BUFFHEAD],DI
MOV WORD PTR [BX.BUFFHEAD+2],ES
MOV WORD PTR ES:[DI.BUFDRV],00FFH ; NEW BUFFER FREE
MOV BX,[BX.MAXSEC]
POP DS
IF NOT HIGHMEM
ADD BX,BUFINSIZ
ADD [MEMLO],BX
ENDIF
JMP DOBUFF
BUF1: CALL ROUND
MOV BX,[MEMHI]
MOV AX,[AREA]
MOV ES,AX ; CALC WHAT WE NEEDED
SUB BX,AX
IF HIGHMEM
DEC BX ; Arena
PUSH BX
ENDIF
MOV AH,SETBLOCK
INT 21H ; GIVE THE REST BACK
IF NOT HIGHMEM
PUSH ES
MOV AX,ES
DEC AX
MOV ES,AX
MOV ES:[arena_owner],8 ; Set impossible owner
POP ES
ENDIF
IF HIGHMEM
MOV BX,0FFFFH
MOV AH,ALLOC
INT 21H
MOV AH,ALLOC
INT 21H
PUSH ES
DEC AX
MOV ES,AX
MOV ES:[arena_owner],8 ; Set impossible owner
POP ES
IF NOT NOEXEC
MOV ES,[AREA]
MOV AH,DEALLOC
INT 21H
ENDIF
POP BX
MOV AX,[AREA]
MOV DS,AX
ADD AX,BX
MOV ES,AX
ELSE
IF NOEXEC
MOV BX,0FFFFH ; ALLOCATE THE REST OF MEM FOR COMMAND
MOV AH,ALLOC
INT 21H
MOV AH,ALLOC
INT 21H
MOV DS,AX
ENDIF
ENDIF
RET
BADOP: MOV DX,OFFSET BADOPM ; WANT TO PRINT COMMAND ERROR
CALL PRINT
JMP COFF
NOPROB: ; GET FILE SIZE (NOTE < 64K!!)
MOV BX,AX
XOR CX,CX
XOR DX,DX
MOV AX,(LSEEK SHL 8) OR 2
INT 21H
MOV [COUNT],AX
XOR DX,DX
MOV AX,LSEEK SHL 8 ; Reset pointer to beginning of file
INT 21H
MOV DX,CS
IF HIGHMEM
MOV AX,OFFSET SYSSIZE + 15
MOV CL,4
SHR AX,CL
ADD DX,AX
ELSE
MOV AX,[COUNT]
ADD AX,15
MOV CL,4
SHR AX,CL ; NUMBER OF SEGMENTS
SUB DX,AX
SUB DX,11H ; ROOM FOR HEADER
ENDIF
MOV DS,DX
MOV ES,DX
ASSUME DS:NOTHING,ES:NOTHING
XOR DX,DX
MOV CX,[COUNT]
MOV AH,READ
STC ; IN CASE OF INT 24
INT 21H ; Function request
PUSHF
PUSH CS
POP DS
ASSUME DS:SYSINITSEG
PUSH AX
MOV AH,CLOSE
INT 21H
POP AX
POPF
JC CONFERR ; IF NOT WE'VE GOT A PROBLEM
CMP CX,AX
JZ GETCOM ; COULDN'T READ THE FILE
CONFERR:
MOV DX,OFFSET CONFIG ; WANT TO PRINT CONFIG ERROR
CALL BADFIL
ENDFILV:JMP ENDFILE
GETCOM:
CALL ORGANIZE ; ORGANIZE THE FILE
CALL GETCHR
CONFLP: JC ENDFILV
MOV AH,AL
CALL GETCHR
CMP AH,'B' ; BUFFER COMMAND?
JNZ TRYC
CALL GETNUM
JZ COFF
CMP AX,100
JAE badop
MOV [BUFFERS],AL
JMP SHORT COFF
TRYC: CMP AH,'C'
JZ GOTC
JMP TRYD
GOTC:
CMP AL,'O' ; FIRST LETTER OF "ON"
JNZ COFF
CALL GETCHR
JC ENDFILV
CMP AL,'N' ; SECOND LETTER OF "ON"
JNZ COFF
MOV AH,SET_CTRL_C_TRAPPING ; TURN ON CONTROL-C CHECK
MOV AL,1
MOV DL,AL
INT 21H
COFF: PUSH CS
POP DS
CALL NEWLINE
JMP CONFLP
TRYD: CMP AH,'D'
JZ GOTD
JMP TRYF
GOTD: MOV BX,CS
MOV DS,BX
MOV WORD PTR [BPB_ADDR],SI
MOV WORD PTR [BPB_ADDR+2],ES
CALL ROUND
IF HIGHMEM
PUSH DS
PUSH ES
POP DS
MOV DX,SI
MOV AX,OPEN SHL 8
STC ; In case INT 24H
INT 21H
POP DS
JC BADBRK
MOV BX,AX
XOR DX,DX
MOV CX,DX
MOV AX,(LSEEK SHL 8) OR 2
INT 21H
PUSH AX
MOV AH,CLOSE
INT 21H
POP AX ; DX:AX is size of file
ADD AX,15
ADC DX,0
MOV CL,4
SHR AX,CL
MOV CL,12
SHL DX,CL
OR AX,DX ; AX is size in PARA
MOV CX,[MEMHI]
SUB [MEMHI],AX
JNC SIZEOK
MOV [MEMHI],CX ; Not enough memory
JMP SHORT BADBRK
SIZEOK:
MOV BX,CS
ENDIF
XOR AX,AX
MOV WORD PTR [ENTRY_POINT],AX
MOV AX,[MEMHI]
MOV WORD PTR [ENTRY_POINT+2],AX ; SET ENTRY POINT
IF NOT NOEXEC
MOV [LDOFF],AX ; SET LOAD OFFSET
ENDIF
PUSH ES
POP DS
MOV DX,SI ; DS:DX POINTS TO FILE NAME
IF NOEXEC
LES BX,DWORD PTR CS:[MEMLO]
CALL LDFIL ; LOAD IN THE DEVICE DRIVER
ELSE
MOV ES,BX
MOV BX,OFFSET PRMBLK ; ES:BX POINTS TO PARAMETERS
MOV AL,3
MOV AH,EXEC
STC ; IN CASE OF INT 24
INT 21H ; LOAD IN THE DEVICE DRIVER
ENDIF
PUSH DS
POP ES ; ES:SI BACK TO CONFIG.SYS
PUSH CS
POP DS ; DS BACK TO SYSINIT
JNC GOODLD
BADBRK: CALL BADLOAD
JMP COFF
GOODLD: PUSH ES ; INITIALIZE THE DEVICE
PUSH SI
PUSH CS
POP ES
MOV BX,SDEVSTRAT
CALL CALLDEV
MOV BX,SDEVINT
CALL CALLDEV
PUSH CS
POP DS
IF NOT HIGHMEM
MOV AX,WORD PTR [BREAK_ADDR+2] ; REMOVE THE INIT CODE
CMP AX,[MEMORY_SIZE]
JB BREAKOK
POP SI
POP ES
JMP BADBRK
BREAKOK:
MOV [MEMHI],AX
MOV AX,WORD PTR [BREAK_ADDR]; REMOVE THE INIT CODE
MOV [MEMLO],AX
ENDIF
LDS DX,[ENTRY_POINT] ; SET DS:DX TO HEADER
MOV SI,DX
ADD SI,SDEVATT ; DS:SI POINTS TO ATTRIBUTES
LES DI,CS:[DOSINFO] ; ES:DI POINT TO DOS INFO
MOV AX,DS:[SI] ; GET ATTRIBUTES
TEST AX,DEVTYP ; TEST IF BLOCK DEV
JZ ISBLOCK
TEST AX,ISCIN ; IS IT A CONSOLE IN?
JZ TRYCLK
MOV WORD PTR ES:[DI.BCON],DX
MOV WORD PTR ES:[DI.BCON+2],DS
TRYCLK: TEST AX,ISCLOCK ; IS IT A CLOCK DEVICE?
JZ GOLINK
MOV WORD PTR ES:[DI+BCLOCK],DX
MOV WORD PTR ES:[DI+BCLOCK+2],DS
GOLINK: JMP LINKIT
ISBLOCK:
MOV AL,CS:[UNITCOUNT] ; IF NO UNITS FOUND....
OR AL,AL
JNZ PERDRV
IF NOT HIGHMEM
MOV CS:[MEMLO],0 ; ...ERASE THE DEVICE
ENDIF
MOV AX,-1
JMP ENDDEV
PERDRV:
CBW
MOV CX,AX
MOV DH,AH
MOV DL,ES:[DI.NUMIO] ; GET NUMBER OF DEVICES
ADD ES:[DI.NUMIO],AL ; UPDATE THE AMOUNT
LDS BX,CS:[BPB_ADDR] ; POINT TO BPB ARRAY
PERUNIT:
LES BP,CS:[DOSINFO]
LES BP,DWORD PTR ES:[BP.DPBHEAD]; GET FIRST DPB
SCANDPB:CMP WORD PTR ES:[BP.DPB_NEXT_DPB],-1
JZ FOUNDPB
LES BP,ES:[BP.DPB_NEXT_DPB]
JMP SCANDPB
FOUNDPB:
MOV AX,CS:[MEMLO]
MOV WORD PTR ES:[BP.DPB_NEXT_DPB],AX
IF HIGHMEM
MOV AX,(DPBSIZ + 15) / 16
SUB CS:[MEMHI],AX
ENDIF
MOV AX,CS:[MEMHI]
MOV WORD PTR ES:[BP.DPB_NEXT_DPB+2],AX
LES BP,DWORD PTR CS:[MEMLO]
IF NOT HIGHMEM
ADD WORD PTR CS:[MEMLO],DPBSIZ
ENDIF
MOV WORD PTR ES:[BP.DPB_NEXT_DPB],-1
MOV ES:[BP.DPB_FIRST_ACCESS],-1
MOV SI,[BX] ; DS:SI POINTS TO BPB
INC BX
INC BX ; POINT TO NEXT GUY
MOV WORD PTR ES:[BP.DPB_DRIVE],DX
MOV AH,SETDPB ; HIDDEN SYSTEM CALL
INT 21H
MOV AX,ES:[BP.DPB_SECTOR_SIZE]
PUSH ES
LES DI,CS:[DOSINFO] ; ES:DI POINT TO DOS INFO
CMP AX,ES:[DI.MAXSEC]
POP ES
JBE NOTMAX
POP SI
POP ES
MOV DX,OFFSET BADSIZ_PRE
MOV BX,OFFSET BADSIZ_POST
CALL PRNERR
JMP COFF
NOTMAX: PUSH DS
PUSH DX
LDS DX,CS:[ENTRY_POINT]
MOV WORD PTR ES:[BP.DPB_DRIVER_ADDR],DX
MOV WORD PTR ES:[BP.DPB_DRIVER_ADDR+2],DS
POP DX
POP DS
INC DX
INC DH
LOOP PERUNIT
LINKIT:
LES DI,CS:[DOSINFO] ; ES:DI = DOS TABLE
MOV CX,WORD PTR ES:[DI.DEVHEAD] ; DX:CX = HEAD OF LIST
MOV DX,WORD PTR ES:[DI.DEVHEAD+2]
LDS SI,CS:[ENTRY_POINT] ; DS:SI = DEVICE LOCATION
MOV WORD PTR ES:[DI.DEVHEAD],SI ; SET HEAD OF LIST IN DOS
MOV WORD PTR ES:[DI.DEVHEAD+2],DS
MOV AX,DS:[SI] ; GET POINTER TO NEXT DEVICE
MOV WORD PTR CS:[ENTRY_POINT],AX; AND SAVE IT
MOV WORD PTR DS:[SI],CX ; LINK IN THE DRIVER
MOV WORD PTR DS:[SI+2],DX
ENDDEV:
POP SI
POP ES
INC AX ; AX = FFFF?
JZ COFFV
JMP GOODLD ; OTHERWISE PRETEND WE LOADED IT IN
COFFV: JMP COFF
TRYQ:
CMP AH,'Q'
JNZ TRYW
CALL GETNUM
JZ COFFV
OR AH,AH
JNZ COFFV
MOV AH,INTERNATIONAL ; AL is country code
MOV DX,-1 ; Set country
INT 21H
JNC COFFV
MOV DX,OFFSET BADCOUNTRY
CALL PRINT
JMP COFFV
TRYF:
CMP AH,'F'
JNZ TRYQ
CALL GETNUM
JZ COFFV
CMP AX,100
JAE TryX
MOV [FILES],AL
JMP COFFV
TRYW:
CMP AH,'W'
JNZ TRYA
MOV DL,AL
MOV AX,(CHAR_OPER SHL 8) OR 1 ; SET SWITCH CHARACTER
MOV [COMMAND_LINE+1],DL