3644d8c222
git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@345 6ac86273-5f31-0410-b378-82cca8765d1b
1070 lines
34 KiB
NASM
1070 lines
34 KiB
NASM
;
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; File:
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; kernel.asm
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; Description:
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; kernel start-up code
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;
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; Copyright (c) 1995, 1996
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; Pasquale J. Villani
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; All Rights Reserved
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;
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; This file is part of DOS-C.
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;
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; DOS-C is free software; you can redistribute it and/or
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; modify it under the terms of the GNU General Public License
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; as published by the Free Software Foundation; either version
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; 2, or (at your option) any later version.
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;
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; DOS-C is distributed in the hope that it will be useful, but
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; WITHOUT ANY WARRANTY; without even the implied warranty of
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; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
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; the GNU General Public License for more details.
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;
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; You should have received a copy of the GNU General Public
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; License along with DOS-C; see the file COPYING. If not,
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; write to the Free Software Foundation, 675 Mass Ave,
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; Cambridge, MA 02139, USA.
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;
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; $Id$
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;
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%include "segs.inc"
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%include "ludivmul.inc"
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segment PSP
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extern _ReqPktPtr:wrt TGROUP
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STACK_SIZE equ 384/2 ; stack allocated in words
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;************************************************************
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; KERNEL BEGINS HERE, i.e. this is byte 0 of KERNEL.SYS
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;************************************************************
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..start:
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entry:
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jmp short realentry
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;************************************************************
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; KERNEL CONFIGURATION AREA
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; this is copied up on the very beginning
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; it's a good idea to keep this in sync with KConfig.h
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;************************************************************
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global _LowKernelConfig
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_LowKernelConfig:
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db 'CONFIG' ; constant
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dw configend-configstart; size of config area
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; to be checked !!!
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configstart:
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DLASortByDriveNo db 0 ; sort disks by drive order
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InitDiskShowDriveAssignment db 1 ;
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SkipConfigSeconds db 2 ;
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ForceLBA db 0 ;
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GlobalEnableLBAsupport db 1 ;
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configend:
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;************************************************************
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; KERNEL CONFIGURATION AREA END
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;************************************************************
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;************************************************************
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; KERNEL real entry (at ~60:20)
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;
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; moves the INIT part of kernel.sys to high memory (~9000:0)
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; then jumps there
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; to aid debugging, some '123' messages are output
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; this area is discardable and used as temporary PSP for the
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; init sequence
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;************************************************************
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realentry: ; execution continues here
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push ax
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push bx
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pushf
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mov ax, 0e31h ; '1' Tracecode - kernel entered
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mov bx, 00f0h
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int 010h
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popf
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pop bx
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pop ax
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jmp far kernel_start
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beyond_entry: resb 256-(beyond_entry-entry)
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; scratch area for data (DOS_PSP)
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segment INIT_TEXT
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extern _FreeDOSmain:wrt I_GROUP
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;
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; kernel start-up
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;
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kernel_start:
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push ax
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push bx
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pushf
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mov ax, 0e32h ; '2' Tracecode - kernel entered
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mov bx, 00f0h
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int 010h
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popf
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pop bx
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pop ax
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mov ax,I_GROUP
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cli
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mov ss,ax
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mov sp,init_tos
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int 12h ; move the init code to higher memory
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mov cl,6
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shl ax,cl
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mov dx,init_end+15
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mov cl,4
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shr dx,cl
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sub ax,dx
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mov es,ax
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mov ax,cs
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mov ds,ax
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xor si,si
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xor di,di
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mov cx,init_end+1
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shr cx,1
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cld
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rep movsw
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push es
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mov ax,cont
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push ax
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retf
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cont: ; inititalize api stacks for high water tests
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mov ax,cs
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mov ss,ax
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mov di,seg apistk_bottom
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mov es,di
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mov di,apistk_bottom
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mov ax,apistk_top
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sub ax,di
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sar ax,1
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mov cx,ax
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mov ax,09090h
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cld
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rep stosw
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; Now set up call frame
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mov ax,DGROUP
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mov ds,ax
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mov es,ax
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mov bp,sp ; and set up stack frame for c
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sti ; now enable them
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push ax
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push bx
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pushf
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mov ax, 0e33h ; '3' Tracecode - kernel entered
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mov bx, 00f0h
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int 010h
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popf
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pop bx
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pop ax
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inc bl
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jns floppy
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add bl,3-1-128
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floppy: mov byte [_BootDrive],bl ; tell where we came from
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;!! int 11h
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;!! mov cl,6
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;!! shr al,cl
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;!! inc al
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;!! mov byte [_NumFloppies],al ; and how many
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mov ax,ss
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mov ds,ax
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mov es,ax
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jmp _FreeDOSmain
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%ifdef WATCOM
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global _IU4M
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_IU4M:
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LMULU
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global _IU4D
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_IU4D:
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LDIVMODU
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%endif
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segment INIT_TEXT_END
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;************************************************************
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; KERNEL CODE AREA END
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; the NUL device
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;************************************************************
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segment _TEXT
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;
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; NUL device strategy
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;
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global _nul_strtgy
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_nul_strtgy:
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mov word [cs:_ReqPktPtr],bx ;save rq headr
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mov word [cs:_ReqPktPtr+2],es
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retf
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;
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; NUL device interrupt
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;
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global _nul_intr
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_nul_intr:
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push es
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push bx
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les bx,[cs:_ReqPktPtr] ;es:bx--> rqheadr
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or word [es:bx+3],100h ;set "done" flag
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pop bx
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pop es
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retf
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;************************************************************
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; KERNEL FIXED DATA AREA
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;************************************************************
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segment _FIXED_DATA
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; Because of the following bytes of data, THIS MODULE MUST BE THE FIRST
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; IN THE LINK SEQUENCE. THE BYTE AT DS:0004 determines the SDA format in
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; use. A 0 indicates MS-DOS 3.X style, a 1 indicates MS-DOS 4.0-6.X style.
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global DATASTART
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DATASTART:
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global _DATASTART
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_DATASTART:
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dos_data db 0
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dw kernel_start
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db 0 ; padding
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dw 1 ; Hardcoded MS-DOS 4.0+ style
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times (0eh - ($ - DATASTART)) db 0
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global _NetBios
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_NetBios dw 0 ; NetBios Number
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times (26h - 0ch - ($ - DATASTART)) db 0
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; Globally referenced variables - WARNING: DO NOT CHANGE ORDER
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; BECAUSE THEY ARE DOCUMENTED AS UNDOCUMENTED (?) AND HAVE
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; MANY MULTIPLEX PROGRAMS AND TSR'S ACCESSING THEM
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global _NetRetry
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_NetRetry dw 3 ;-000c network retry count
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global _NetDelay
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_NetDelay dw 1 ;-000a network delay count
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global _DskBuffer
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_DskBuffer dd -1 ;-0008 current dos disk buffer
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dw 0 ;-0004 Unread con input
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global _first_mcb
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_first_mcb dw 0 ;-0002 Start of user memory
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global _DPBp
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global MARK0026H
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; A reference seems to indicate that this should start at offset 26h.
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MARK0026H equ $
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_DPBp dd 0 ; 0000 First drive Parameter Block
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global _sfthead
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_sfthead dw _firstsftt ; 0004 System File Table head
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dw seg _firstsftt
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global _clock
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_clock dd 0 ; 0008 CLOCK$ device
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global _syscon
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_syscon dw _con_dev,seg _con_dev ; 000c console device
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global _maxbksize
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_maxbksize dw 512 ; 0010 maximum bytes/sector of any block device
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dw buf_info ; 0012 pointer to buffers info structure
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dw seg buf_info
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global _CDSp
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_CDSp dd 0 ; 0016 Current Directory Structure
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global _FCBp
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_FCBp dd 0 ; 001a FCB table pointer
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global _nprotfcb
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_nprotfcb dw 0 ; 001e number of protected fcbs
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global _nblkdev
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_nblkdev db 0 ; 0020 number of block devices
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global _lastdrive
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_lastdrive db 0 ; 0021 value of last drive
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global _nul_dev
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_nul_dev: ; 0022 device chain root
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extern _con_dev:wrt TGROUP
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dw _con_dev, seg _con_dev
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; next is con_dev at init time.
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dw 8004h ; attributes = char device, NUL bit set
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dw _nul_strtgy
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dw _nul_intr
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db 'NUL '
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global _njoined
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_njoined db 0 ; 0034 number of joined devices
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dw 0 ; 0035 DOS 4 pointer to special names (always zero in DOS 5)
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setverPtr dw 0,0 ; 0037 setver list
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dw 0 ; 003B cs offset for fix a20
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dw 0 ; 003D psp of last umb exec
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global _LoL_nbuffers
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_LoL_nbuffers dw 1 ; 003F number of buffers
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dw 1 ; 0041 size of pre-read buffer
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global _BootDrive
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_BootDrive db 1 ; 0043 drive we booted from
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%IFNDEF I386
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db 0 ; 0044 cpu type (1 if >=386)
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%ELSE
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db 1 ; 0044 cpu type (1 if >=386)
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%ENDIF
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dw 0 ; 0045 Extended memory in KBytes
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buf_info:
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global _firstbuf
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_firstbuf dd 0 ; 0047 disk buffer chain
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dw 0 ; 004B 0 (DOS 4 = # hashing chains)
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dd 0 ; 004D pre-read buffer
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dw 0 ; 0051 # of sectors
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db 0 ; 0053 00=conv 01=HMA
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dw 0 ; 0054 deblock buf in conv
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deblock_seg dw 0 ; 0056 (offset always zero)
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times 3 db 0 ; 0058 unknown
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dw 0 ; 005B unknown
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db 0, 0FFh, 0 ; 005D unknown
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global _VgaSet
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_VgaSet db 0 ; 0060 unknown
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dw 0 ; 0061 unknown
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global _uppermem_link
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_uppermem_link db 0 ; 0063 upper memory link flag
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_min_pars dw 0 ; 0064 minimum paragraphs of memory
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; required by program being EXECed
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global _uppermem_root
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_uppermem_root dw 0 ; 0066 dmd_upper_root (usually 9fff)
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_last_para dw 0 ; 0068 para of last mem search
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SysVarEnd:
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;; The first 5 sft entries appear to have to be at DS:00cc
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times (0cch - ($ - DATASTART)) db 0
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global _firstsftt
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_firstsftt:
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dd -1 ; link to next
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dw 5 ; count
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; Some references seem to indicate that this data should start at 01fbh in
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; order to maintain 100% MS-DOS compatibility.
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times (01fbh - ($ - DATASTART)) db 0
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global MARK01FBH
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MARK01FBH equ $
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times 128 db 0
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global _kb_buf
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_kb_buf db 129,0 ; initialise buffer to empty
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times 128+1 db 0 ; room for 128 byte readline + LF
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;
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; Variables that follow are documented as part of the DOS 4.0-6.X swappable
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; data area in Ralf Browns Interrupt List #56
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;
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; this byte is used for ^P support
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global _PrinterEcho
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_PrinterEcho db 0 ;-34 - 0 = no printer echo, ~0 echo
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global _verify_ena
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_verify_ena db 0 ; ~0, write with verify
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; this byte is used for TAB's
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global _scr_pos
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_scr_pos db 0 ; Current Cursor Column
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global _switchar
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_switchar db '/' ;-31 - switch char
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global _mem_access_mode
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_mem_access_mode db 0 ;-30 - memory allocation strategy
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global sharing_flag
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sharing_flag db 0 ; 00 = sharing module not loaded
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; 01 = sharing module loaded, but
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; open/close for block devices
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; disabled
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; FF = sharing module loaded,
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; open/close for block devices
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; enabled (not implemented)
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global _net_set_count
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_net_set_count db 1 ;-28 - count the name below was set
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global _net_name
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_net_name db ' ' ;-27 - 15 Character Network Name
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db 00 ; Terminating 0 byte
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;
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; Variables contained the the "STATE_DATA" segment contain
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; information about the STATE of the current DOS Process. These
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; variables must be preserved regardless of the state of the INDOS
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; flag.
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;
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; All variables that appear in "STATE_DATA" **MUST** be declared
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; in this file as the offsets from the INTERNAL_DATA variable are
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; critical to the DOS applications that modify this data area.
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;
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;
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global _ErrorMode, _InDOS
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global _CritErrLocus, _CritErrCode
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global _CritErrAction, _CritErrClass
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global _CritErrDev, _CritErrDrive
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global _dta
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global _cu_psp, _default_drive
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global _break_ena
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global _return_code, _return_mode
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global _internal_data
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global _CritPatch
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_CritPatch dw 0d0ch ;-11 zero list of patched critical
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dw 0d0ch ; section variables
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dw 0d0ch
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dw 0d0ch
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dw 0d0ch
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db 0 ;-01 - unknown
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_internal_data: ; <-- Address returned by INT21/5D06
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_ErrorMode db 0 ; 00 - Critical Error Flag
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_InDOS db 0 ; 01 - Indos Flag
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_CritErrDrive db 0 ; 02 - Drive on write protect error
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_CritErrLocus db 0 ; 03 - Error Locus
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_CritErrCode dw 0 ; 04 - DOS format error Code
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_CritErrAction db 0 ; 06 - Error Action Code
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_CritErrClass db 0 ; 07 - Error Class
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_CritErrDev dd 0 ; 08 - Failing Device Address
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_dta dw _TempBuffer, seg _TempBuffer
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; 0C - current DTA, initialize to TempBuffer.
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_cu_psp dw 0 ; 10 - Current PSP
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break_sp dw 0 ; 12 - used in int 23
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_return_code db 0 ; 14 - return code from process
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_return_mode db 0 ; 15 - reason for process terminate
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_default_drive db 0 ; 16 - Current Drive
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_break_ena db 1 ; 17 - Break Flag (default TRUE)
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db 0 ; 18 - flag, code page switching
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db 0 ; 19 - flag, copy of 18 on int 24h abort
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global _swap_always, _swap_indos
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_swap_always:
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global _Int21AX
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_Int21AX dw 0 ; 1A - AX from last Int 21
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global owning_psp, _MachineId
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owning_psp dw 0 ; 1C - owning psp
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_MachineId dw 0 ; 1E - remote machine ID
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dw 0 ; 20 - First usable mcb
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dw 0 ; 22 - Best usable mcb
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dw 0 ; 24 - Last usable mcb
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dw 0 ; 26 - memory size in paragraphs
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dw 0 ; 28 - unknown
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db 0 ; 2A - unknown
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db 0 ; 2B - unknown
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db 0 ; 2C - unknown
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global _break_flg
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_break_flg db 0 ; 2D - Program aborted by ^C
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db 0 ; 2E - unknown
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db 0 ; 2F - not referenced
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global _DayOfMonth
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_DayOfMonth db 1 ; 30 - day of month
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global _Month
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_Month db 1 ; 31 - month
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global _YearsSince1980
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_YearsSince1980 dw 0 ; 32 - year since 1980
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daysSince1980 dw 0FFFFh ; 34 - number of days since epoch
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; force rebuild on first clock read
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global _DayOfWeek
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_DayOfWeek db 2 ; 36 - day of week
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global _Year
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_Year dw 1980 ; 37 - year
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global _dosidle_flag
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_dosidle_flag db 0 ; 39 - unknown *no more*
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global _CharReqHdr
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_CharReqHdr:
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global _ClkReqHdr
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_ClkReqHdr times 30 db 0 ; 3A - Device driver request header
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dd 0 ; 58 - pointer to driver entry
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global _MediaReqHdr
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_MediaReqHdr times 22 db 0 ; 5C - Device driver request header
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global _IoReqHdr
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_IoReqHdr times 30 db 0 ; 72 - Device driver request header
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times 6 db 0 ; 90 - unknown
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global _ClkRecord
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_ClkRecord times 6 db 0 ; 96 - CLOCK$ transfer record
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dw 0 ; 9C - unknown
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global __PriPathBuffer
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__PriPathBuffer times 80h db 0 ; 9E - buffer for file name
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global __SecPathBuffer
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__SecPathBuffer times 80h db 0 ;11E - buffer for file name
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global _TempBuffer
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_TempBuffer times 21 db 0 ;19E - 21 byte srch state
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global _SearchDir
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_SearchDir times 32 db 0 ;1B3 - 32 byte dir entry
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global _TempCDS
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_TempCDS times 88 db 0 ;1D3 - TemporaryCDS buffer
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global _DirEntBuffer
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_DirEntBuffer times 32 db 0 ;22B - space enough for 1 dir entry
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global _wAttr
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_wAttr dw 0 ;24B - extended FCB file attribute
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global _SAttr
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_SAttr db 0 ;24D - Attribute Mask for Dir Search
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global _OpenMode
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_OpenMode db 0 ;24E - File Open Attribute
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times 3 db 0
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global _Server_Call
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_Server_Call db 0 ;252 - Server call Func 5D sub 0
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db 0
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global _lpUserStack
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_lpUserStack dd 0 ;254 - pointer to user stack frame
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; Pad to 057Ch
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times (25ch - ($ - _internal_data)) db 0
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global _tsr ; used by break and critical error
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_tsr db 0 ;25C - handlers during termination
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db 0 ;25D - padding
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global term_psp
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term_psp dw 0 ;25E - 0??
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global int24_esbp
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int24_esbp times 2 dw 0 ;260 - pointer to criticalerr DPB
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global _user_r, int21regs_off, int21regs_seg
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_user_r:
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int21regs_off dw 0 ;264 - pointer to int21h stack frame
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int21regs_seg dw 0
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global critical_sp
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critical_sp dw 0 ;268 - critical error internal stack
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global current_ddsc
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current_ddsc times 2 dw 0
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|
|
; Pad to 059ah
|
|
times (27ah - ($ - _internal_data)) db 0
|
|
global current_device
|
|
current_device times 2 dw 0 ;27A - 0??
|
|
global _lpCurSft
|
|
_lpCurSft times 2 dw 0 ;27e - Current SFT
|
|
global _current_ldt
|
|
_current_ldt times 2 dw 0 ;282 - Current CDS
|
|
global _lpFcb
|
|
_lpFcb times 2 dw 0 ;286 - pointer to callers FCB
|
|
global _current_sft_idx
|
|
_current_sft_idx dw 0 ;28A - SFT index for next open
|
|
; used by MS NET
|
|
|
|
; Pad to 05b2h
|
|
times (292h - ($ - _internal_data)) db 0
|
|
dw __PriPathBuffer ; 292 - "sda_WFP_START" offset in DOS DS of first filename argument
|
|
dw __SecPathBuffer ; 294 - "sda_REN_WFP" offset in DOS DS of second filename argument
|
|
|
|
; Pad to 05ceh
|
|
times (2aeh - ($ - _internal_data)) db 0
|
|
global _current_filepos
|
|
_current_filepos times 2 dw 0 ;2AE - current offset in file
|
|
|
|
; Pad to 05f0h
|
|
times (2d0h - ($ - _internal_data)) db 0
|
|
global _prev_user_r
|
|
global prev_int21regs_off
|
|
global prev_int21regs_seg
|
|
_prev_user_r:
|
|
prev_int21regs_off dw 0 ;2D0 - pointer to prev int 21 frame
|
|
prev_int21regs_seg dw 0
|
|
|
|
; Pad to 0620h
|
|
times (300h - ($ - _internal_data)) db 0
|
|
global _szNames
|
|
_szNames:
|
|
;; times 11 db 0
|
|
|
|
global _FcbSearchBuffer ; during FCB search 1st/next use bottom
|
|
_FcbSearchBuffer: ; of error stack as scratch buffer
|
|
; times 43 db 0 ; - only used during int 21 call
|
|
; stacks are made to initialize to no-ops so that high-water
|
|
; testing can be performed
|
|
|
|
global apistk_bottom
|
|
apistk_bottom:
|
|
times STACK_SIZE dw 0 ;300 - Error Processing Stack
|
|
global _error_tos
|
|
_error_tos:
|
|
times STACK_SIZE dw 0 ;480 - Disk Function Stack
|
|
global _disk_api_tos
|
|
_disk_api_tos:
|
|
times STACK_SIZE dw 0 ;600 - Char Function Stack
|
|
global _char_api_tos
|
|
_char_api_tos:
|
|
apistk_top:
|
|
db 0 ; 780 ???
|
|
_VolChange db 0 ;781 - volume change
|
|
_VirtOpen db 0 ;782 - virtual open flag
|
|
|
|
; controlled variables end at offset 78Ch so pad to end
|
|
times (78ch - ($ - _internal_data)) db 0
|
|
|
|
;
|
|
; end of controlled variables
|
|
;
|
|
|
|
segment _BSS
|
|
;!! global _NumFloppies
|
|
;!!_NumFloppies resw 1
|
|
;!!intr_dos_stk resw 1
|
|
;!!intr_dos_seg resw 1
|
|
|
|
|
|
; mark front and end of bss area to clear
|
|
segment IB_B
|
|
global __ib_start
|
|
__ib_start:
|
|
segment IB_E
|
|
global __ib_end
|
|
__ib_end:
|
|
;; do not clear the other init BSS variables + STACK: too late.
|
|
|
|
retoff resw 1 ; return offset to jump to from HMA_TEXT
|
|
|
|
; kernel startup stack
|
|
global init_tos
|
|
resw 512
|
|
init_tos:
|
|
; the last paragraph of conventional memory might become an MCB
|
|
resb 16
|
|
global __init_end
|
|
__init_end:
|
|
init_end:
|
|
|
|
segment _DATA
|
|
; blockdev private stack
|
|
global blk_stk_top
|
|
times 192 dw 0
|
|
blk_stk_top:
|
|
|
|
; clockdev private stack
|
|
global clk_stk_top
|
|
times 64 dw 0
|
|
clk_stk_top:
|
|
|
|
; Dynamic data:
|
|
; member of the DOS DATA GROUP
|
|
; and marks definitive end of all used data in kernel data segment
|
|
;
|
|
|
|
segment _DATAEND
|
|
|
|
_swap_indos:
|
|
; we don't know precisely what needs to be swapped before this, so set it here.
|
|
; this is just after FIXED_DATA+BSS+DATA and before (D)CONST+BSS
|
|
; probably, the clock and block stacks and disktransferbuffer should go past
|
|
; _swap_indos but only if int2a ah=80/81 (critical section start/end)
|
|
; are called upon entry and exit of the device drivers
|
|
|
|
segment DYN_DATA
|
|
|
|
global _Dyn
|
|
_Dyn:
|
|
DynAllocated dw 0
|
|
|
|
segment ID_B
|
|
global __INIT_DATA_START
|
|
__INIT_DATA_START:
|
|
segment ID_E
|
|
global __INIT_DATA_END
|
|
__INIT_DATA_END:
|
|
|
|
|
|
segment INIT_TEXT_START
|
|
global __InitTextStart
|
|
__InitTextStart: ; and c version
|
|
|
|
|
|
;
|
|
; start end end of HMA area
|
|
|
|
segment HMA_TEXT_START
|
|
global __HMATextAvailable
|
|
__HMATextAvailable
|
|
global __HMATextStart
|
|
__HMATextStart:
|
|
|
|
;
|
|
; the HMA area is filled with 1eh+3(=sizeof VDISK) = 33 byte dummy data,
|
|
; so nothing will ever be below 0xffff:0031
|
|
;
|
|
segment HMA_TEXT
|
|
begin_hma:
|
|
times 10h db 0 ; filler [ffff:0..ffff:10]
|
|
times 20h db 0
|
|
db 0
|
|
|
|
%ifdef WATCOM
|
|
; 32 bit multiplication + division
|
|
global __U4M
|
|
__U4M:
|
|
LMULU
|
|
global __U4D
|
|
__U4D:
|
|
LDIVMODU
|
|
%endif
|
|
|
|
init_ret_np: push ds
|
|
push word [retoff]
|
|
retf ; return from init_calls.
|
|
|
|
;End of HMA segment
|
|
segment HMA_TEXT_END
|
|
global __HMATextEnd
|
|
__HMATextEnd: ; and c version
|
|
|
|
|
|
|
|
; The default stack (_TEXT:0) will overwrite the data area, so I create a dummy
|
|
; stack here to ease debugging. -- ror4
|
|
|
|
segment _STACK class=STACK stack
|
|
|
|
|
|
|
|
|
|
|
|
segment _TEXT
|
|
; dummy interrupt return handlers
|
|
|
|
global _int22_handler
|
|
global _int28_handler
|
|
global _int2a_handler
|
|
global _empty_handler
|
|
_int22_handler:
|
|
_int28_handler:
|
|
_int2a_handler:
|
|
_empty_handler:
|
|
iret
|
|
|
|
|
|
; to minimize relocations
|
|
global _DGROUP_
|
|
_DGROUP_:
|
|
dw DGROUP
|
|
|
|
|
|
segment INIT_TEXT
|
|
|
|
call far initforceEnableA20 ; first enable A20 or not
|
|
manip_stack_A20:
|
|
pop dx ; get last ret address
|
|
pop word [retoff] ; get near ret address of init caller
|
|
mov ax, init_ret_np ; new init caller ret address
|
|
push ax
|
|
jmp dx ; and back to the relocation entry
|
|
|
|
global __HMAinitRelocationTableStart
|
|
__HMAinitRelocationTableStart:
|
|
|
|
extern _execrh
|
|
global _reloc_call_execrh
|
|
_reloc_call_execrh:
|
|
call manip_stack_A20
|
|
jmp far _execrh
|
|
|
|
extern _fmemcpy
|
|
global _reloc_call_fmemcpy
|
|
_reloc_call_fmemcpy:
|
|
call manip_stack_A20
|
|
jmp far _fmemcpy
|
|
|
|
extern _strcpy
|
|
global _reloc_call_strcpy
|
|
_reloc_call_strcpy:
|
|
call manip_stack_A20
|
|
jmp far _strcpy
|
|
|
|
extern _fstrncpy
|
|
global _reloc_call_fstrncpy
|
|
_reloc_call_fstrncpy:
|
|
call manip_stack_A20
|
|
jmp far _fstrncpy
|
|
|
|
extern _strlen
|
|
global _reloc_call_strlen
|
|
_reloc_call_strlen:
|
|
call manip_stack_A20
|
|
jmp far _strlen
|
|
|
|
extern _fstrlen
|
|
global _reloc_call_fstrlen
|
|
_reloc_call_fstrlen:
|
|
call manip_stack_A20
|
|
jmp far _fstrlen
|
|
|
|
extern _fmemset
|
|
global _reloc_call_fmemset
|
|
_reloc_call_fmemset:
|
|
call manip_stack_A20
|
|
jmp far _fmemset
|
|
|
|
extern _memset
|
|
global _reloc_call_memset
|
|
_reloc_call_memset:
|
|
call manip_stack_A20
|
|
jmp far _memset
|
|
|
|
global __HMAinitRelocationTableEnd
|
|
__HMAinitRelocationTableEnd:
|
|
|
|
segment _TEXT
|
|
|
|
global _initforceEnableA20
|
|
initforceEnableA20:
|
|
call near forceEnableA20
|
|
retf
|
|
|
|
global __HMARelocationTableStart
|
|
__HMARelocationTableStart:
|
|
|
|
global _int2f_handler
|
|
extern reloc_call_int2f_handler
|
|
_int2f_handler: jmp far reloc_call_int2f_handler
|
|
call near forceEnableA20
|
|
|
|
global _int20_handler
|
|
extern reloc_call_int20_handler
|
|
_int20_handler: jmp far reloc_call_int20_handler
|
|
call near forceEnableA20
|
|
|
|
global _int21_handler
|
|
extern reloc_call_int21_handler
|
|
_int21_handler: jmp far reloc_call_int21_handler
|
|
call near forceEnableA20
|
|
|
|
|
|
global _low_int25_handler
|
|
extern reloc_call_low_int25_handler
|
|
_low_int25_handler: jmp far reloc_call_low_int25_handler
|
|
call near forceEnableA20
|
|
|
|
global _low_int26_handler
|
|
extern reloc_call_low_int26_handler
|
|
_low_int26_handler: jmp far reloc_call_low_int26_handler
|
|
call near forceEnableA20
|
|
|
|
global _int27_handler
|
|
extern reloc_call_int27_handler
|
|
_int27_handler: jmp far reloc_call_int27_handler
|
|
call near forceEnableA20
|
|
|
|
global _int0_handler
|
|
extern reloc_call_int0_handler
|
|
_int0_handler: jmp far reloc_call_int0_handler
|
|
call near forceEnableA20
|
|
|
|
global _int6_handler
|
|
extern reloc_call_int6_handler
|
|
_int6_handler: jmp far reloc_call_int6_handler
|
|
call near forceEnableA20
|
|
|
|
global _cpm_entry
|
|
extern reloc_call_cpm_entry
|
|
_cpm_entry: jmp far reloc_call_cpm_entry
|
|
call near forceEnableA20
|
|
|
|
global _reloc_call_blk_driver
|
|
extern _blk_driver
|
|
_reloc_call_blk_driver:
|
|
jmp far _blk_driver
|
|
call near forceEnableA20
|
|
|
|
global _reloc_call_clk_driver
|
|
extern _clk_driver
|
|
_reloc_call_clk_driver:
|
|
jmp far _clk_driver
|
|
call near forceEnableA20
|
|
|
|
global _CharMapSrvc
|
|
extern _reloc_call_CharMapSrvc
|
|
_CharMapSrvc: jmp far _reloc_call_CharMapSrvc
|
|
call near forceEnableA20
|
|
|
|
|
|
global __HMARelocationTableEnd
|
|
__HMARelocationTableEnd:
|
|
|
|
;
|
|
; if we were lucky, we found all entries from the outside to the kernel.
|
|
; if not, BUMS
|
|
;
|
|
;
|
|
; this routine makes the HMA area available. PERIOD.
|
|
; must conserve ALL registers
|
|
; will be only ever called, if HMA (DOS=HIGH) is enabled.
|
|
; for obvious reasons it should be located at the relocation table
|
|
;
|
|
global _XMSDriverAddress
|
|
_XMSDriverAddress:
|
|
dw 0 ; XMS driver, if detected
|
|
dw 0
|
|
|
|
global __EnableA20
|
|
__EnableA20:
|
|
mov ah,3
|
|
UsingXMSdriver:
|
|
push bx
|
|
call far [cs:_XMSDriverAddress]
|
|
pop bx
|
|
retf
|
|
|
|
global __DisableA20
|
|
__DisableA20:
|
|
mov ah,4
|
|
jmp short UsingXMSdriver
|
|
|
|
dslowmem dw 0
|
|
eshighmem dw 0ffffh
|
|
|
|
global forceEnableA20
|
|
forceEnableA20:
|
|
|
|
push ds
|
|
push es
|
|
push ax
|
|
|
|
forceEnableA20retry:
|
|
mov ds, [cs:dslowmem]
|
|
mov es, [cs:eshighmem]
|
|
|
|
mov ax, [ds:00000h]
|
|
cmp ax, [es:00010h]
|
|
jne forceEnableA20success
|
|
|
|
mov ax, [ds:00002h]
|
|
cmp ax, [es:00012h]
|
|
jne forceEnableA20success
|
|
|
|
mov ax, [ds:00004h]
|
|
cmp ax, [es:00014h]
|
|
jne forceEnableA20success
|
|
|
|
mov ax, [ds:00006h]
|
|
cmp ax, [es:00016h]
|
|
jne forceEnableA20success
|
|
|
|
;
|
|
; ok, we have to enable A20 )at least seems so
|
|
;
|
|
; some debug first
|
|
; push bx
|
|
; mov ah, 0eh
|
|
; mov al, 'H'
|
|
; mov bx, 0007h
|
|
; int 10h
|
|
; pop bx
|
|
|
|
call far __EnableA20
|
|
|
|
jmp short forceEnableA20retry
|
|
|
|
|
|
|
|
forceEnableA20success:
|
|
pop ax
|
|
pop es
|
|
pop ds
|
|
ret
|
|
|
|
|
|
|
|
|
|
|
|
|
|
segment _TEXT
|
|
;
|
|
; Default Int 24h handler -- always returns fail
|
|
; so we have not to relocate it (now)
|
|
;
|
|
FAIL equ 03h
|
|
|
|
global _int24_handler
|
|
_int24_handler: mov al,FAIL
|
|
iret
|
|
|
|
;
|
|
; this makes some things easier
|
|
;
|
|
|
|
segment _TEXT
|
|
global _TEXT_DGROUP
|
|
_TEXT_DGROUP dw DGROUP
|
|
|
|
segment INIT_TEXT
|
|
global _INIT_DGROUP
|
|
_INIT_DGROUP dw DGROUP
|
|
|
|
|
|
; Log: kernel.asm,v
|
|
; Revision 1.6 2000/03/09 06:07:11 kernel
|
|
; 2017f updates by James Tabor
|
|
;
|
|
; Revision 1.5 1999/09/23 04:40:47 jprice
|
|
; *** empty log message ***
|
|
;
|
|
; Revision 1.3 1999/08/10 17:57:13 jprice
|
|
; ror4 2011-02 patch
|
|
;
|
|
; Revision 1.2 1999/04/13 15:52:57 jprice
|
|
; changes for boot loader
|
|
;
|
|
; Revision 1.1.1.1 1999/03/29 15:41:14 jprice
|
|
; New version without IPL.SYS
|
|
;
|
|
; Revision 1.4 1999/02/08 05:55:57 jprice
|
|
; Added Pat's 1937 kernel patches
|
|
;
|
|
; Revision 1.3 1999/02/01 01:48:41 jprice
|
|
; Clean up; Now you can use hex numbers in config.sys. added config.sys screen function to change screen mode (28 or 43/50 lines)
|
|
;
|
|
; Revision 1.2 1999/01/22 04:13:26 jprice
|
|
; Formating
|
|
;
|
|
; Revision 1.1.1.1 1999/01/20 05:51:01 jprice
|
|
; Imported sources
|
|
;
|
|
; Rev 1.11 06 Dec 1998 8:48:04 patv
|
|
;Bug fixes.
|
|
;
|
|
; Rev 1.10 03 Feb 1998 23:30:08 patv
|
|
;Added a start-up stack for loadable device drivers. Need the separate
|
|
;stack so that all int 21h functions can be called.
|
|
;
|
|
; Rev 1.9 22 Jan 1998 4:09:24 patv
|
|
;Fixed pointer problems affecting SDA
|
|
;
|
|
; Rev 1.8 06 Jan 1998 20:12:32 patv
|
|
;Reduced device driver stack sizes.
|
|
;
|
|
; Rev 1.7 04 Jan 1998 17:26:18 patv
|
|
;Corrected subdirectory bug
|
|
;
|
|
; Rev 1.6 03 Jan 1998 8:36:50 patv
|
|
;Converted data area to SDA format
|
|
;
|
|
; Rev 1.5 06 Feb 1997 22:43:18 patv
|
|
;Reduced stack sizes for block and clock devices.
|
|
;
|
|
; Rev 1.4 06 Feb 1997 19:05:48 patv
|
|
;Added hooks for tsc command
|
|
;
|
|
; Rev 1.3 29 May 1996 21:03:44 patv
|
|
;bug fixes for v0.91a
|
|
;
|
|
; Rev 1.2 19 Feb 1996 3:24:06 patv
|
|
;Added NLS, int2f and config.sys processing
|
|
;
|
|
; Rev 1.1 01 Sep 1995 17:54:24 patv
|
|
;First GPL release.
|
|
;
|
|
; Rev 1.0 02 Jul 1995 9:05:44 patv
|
|
;Initial revision.
|
|
;
|
|
; EndLog
|
|
;
|