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Baron-von-RiedeselBaron-von-Riedesel
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v1.27
1 parent accdbb0 commit dd6f150

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Lines changed: 733 additions & 45 deletions

‎DEBUG.TXT‎

Lines changed: 19 additions & 13 deletions
Original file line numberDiff line numberDiff line change
@@ -86,7 +86,14 @@ offset address with a colon. Some examples using the Dump command:
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-D DS:100 102
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-D SS:20 L 4
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[ENH: DEBUGX understand this additional syntax:
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[ENH: the command prompt is changed if the debuggee has been stopped
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inside DOS - a '!' will precede the default prompt ('!-' instead of
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just '-'). DEBUGX changes the prompt to '#' if debuggee is in protected-
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mode. Prompt '!#', which means "inside DOS" AND "in protected-mode",
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is also possible, if the debuggee has been stopped in a so-called
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DPMI real-mode callback.
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As for the Dump command, DEBUGX understands this additional syntax:
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#D $F000:FFF6
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@@ -97,9 +104,8 @@ if debuggee is in protected-mode and the segment part of the starting
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address is a 32bit selector, the offset parts of the starting and ending
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address - as well as the length - can be 32bit. Examples:
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100-
-D DS:110000 110FFF
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-D CS:400000 L 20000
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#D DS:110000 110FFF
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#D CS:400000 L 20000
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]
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---
@@ -251,15 +257,15 @@ The Go command (G), when used without a parameter, causes DEBUG to
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copy the contents of the register variables to the actual CPU
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registers and effectively jump to the instruction at CS:IP, giving
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full control to the program being debugged. DEBUG will reassert
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control when the program terminates normally, or DEBUG will not
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reassert control. The optional address parameter can be used to
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specify the starting address. The optional breakpoint list can
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be used to specify up to 10 temporary breakpoint addresses.
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To differentiate the address parameter from the breakpoint list,
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the address parameter must be preceded with an "=". Note that the
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breakpoint addresses must coincide with the start of a valid
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instruction. To resume execution after a breakpoint, use the Go
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command without a parameter.
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control when the program terminates normally, a debug exception
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(exception 01) or a hard-coded breakpoint (INT 03) is reached.
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The optional address parameter can be used to specify the starting
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address. The optional breakpoint list can be used to specify up to
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10 temporary breakpoint addresses. To differentiate the address
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parameter from the breakpoint list, the address parameter must be
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preceded with an "=". Note that the breakpoint addresses must coincide
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with the start of a valid instruction. To resume execution after a
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breakpoint, use the Go command without a parameter.
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Syntax: G [=address] [break0 break1...]
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‎HISTORY.TXT‎

Lines changed: 9 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -214,10 +214,16 @@
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break in real-mode.
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- bugfix 'xs' cmd: no of pages of just the first handle was displayed,
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and the handle total was not correct.
217-
1.27 [ ?? 2020]
217+
1.27 [08 November 2020]
218218
- added new variant DEBUGXU.COM. This version does not use int 15h,
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ah=87h inside the DX command, thus avoiding to disable a possibly
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active unreal mode. The catch is that this version's DX command won't
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work in V86 mode.
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- disassembler handles operand size prefix for one-byte push command
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correctly: 66h, 6Ah, 00h -> 'PUSH DWORD +00'.
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- disassembler handles operand size prefix for one-byte "push <imm>"
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opcodes correctly. OTOH, for 2/4 byte "push <imm>" opcodes, the
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disassembler no longer displays the operand size, since the size
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is obvious.
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- if InDOS flag is set, a '!' is preceding the debugger prompt.
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- BIOS used when waiting for a key in help msg display.
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- 'e' cmd uses BIOS if InDOS flag set.
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‎MAKE.BAT‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -2,5 +2,5 @@
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echo creating debug.com
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jwasm -nologo -D?PM=0 -bin -Fobuild\DEBUG.COM -Flbuild\DEBUG.LST src\debug.asm
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echo creating debugx.com
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jwasm -c -nologo -D?PM=1 -bin -Fo build\DEBUGX.COM -Flbuild\DEBUGX.LST src\debug.asm
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jwasm -nologo -D?PM=1 -bin -Fo build\DEBUGX.COM -Flbuild\DEBUGX.LST src\debug.asm
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rem ml -c -nologo -D?PM=1 -Fo build\DEBUGX.OBJ -Flbuild\DEBUGX.LST src\debug.asm

‎MAKEC.BAT‎

100644100755
Lines changed: 8 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -5,4 +5,11 @@ rem 1) instr.set
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rem 2) instr.key
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rem 3) instr.ord
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rem 4) mktables.c
8-
wcl -ox -3 -d__MSDOS__ mktables.c
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rem using Open Watcom
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rem wcl -ox -3 -d__MSDOS__ src\mktables.c
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rem using MSVC v1.5
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\msvc\bin\cl -c -G3 -D__MSDOS__ -Fobuild\mktables.obj -I\msvc\include src\mktables.c
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set lib=\msvc\lib
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\msvc\bin\link16 build\mktables.obj,build\mktables.exe,build\mktables.map /NON;

‎Samples/DPMIBK16.ASM‎

Lines changed: 143 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,143 @@
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;--- DPMIBK16.ASM: 16bit DPMI application written in MASM syntax.
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;--- this sample temporarily switches back to real-mode.
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;--- assemble: JWasm -bin -Fo dpmibk16.com dpmibk16.asm
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LF equ 10
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CR equ 13
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.286
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.model tiny
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;--- DPMI real-mode call structure
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RMCS struct
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rEDI dd ?
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rESI dd ?
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rEBP dd ?
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dd ?
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rEBX dd ?
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rEDX dd ?
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rECX dd ?
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rEAX dd ?
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rFlags dw ?
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rES dw ?
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rDS dw ?
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rFS dw ?
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rGS dw ?
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rIP dw ?
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rCS dw ?
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rSP dw ?
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rSS dw ?
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RMCS ends
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.code
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org 100h
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;--- the 16bit initialization part
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start:
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pop ax ;get word saved on stack for COM files
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mov bx, sp
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shr bx, 4
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jnz @F
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mov bx,1000h ;it was a full 64kB stack
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@@:
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mov ah, 4Ah ;free unused memory
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int 21h
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mov ax, 1687h ;DPMI host installed?
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int 2Fh
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and ax, ax
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jnz nohost
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push es ;save DPMI entry address
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push di
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and si, si ;requires host client-specific DOS memory?
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jz nomemneeded
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mov bx, si
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mov ah, 48h ;alloc DOS memory
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int 21h
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jc nomem
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mov es, ax
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nomemneeded:
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mov bp, sp
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mov bx, cs ;save real-mode value of CS in BX
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mov ax, 0000 ;start a 16-bit client
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call far ptr [bp] ;initial switch to protected-mode
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jnc initok
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call error
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db "DPMI initialisation failed",CR,LF,'$'
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nohost:
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call error
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db "no DPMI host installed",CR,LF,'$'
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nomem:
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call error
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db "not enough DOS memory for initialisation",CR,LF,'$'
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error:
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push cs
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pop ds
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pop dx
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mov ah, 9
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int 21h
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mov ax, 4C00h
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int 21h
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;--- now in protected-mode
86+
87+
initok:
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push bx
89+
call printstring
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db "welcome in protected-mode",CR,LF,0
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pop bx
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;--- switch back to real-mode
94+
95+
sub sp, sizeof RMCS
96+
mov bp,sp
97+
mov [bp].RMCS.rIP, offset backinreal
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mov [bp].RMCS.rCS, bx
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xor ax, ax
100+
mov [bp].RMCS.rFlags, ax
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mov [bp].RMCS.rDS, ax
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mov [bp].RMCS.rES, ax
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lea ax,[bp-20h]
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mov [bp].RMCS.rSP, ax
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mov [bp].RMCS.rSS, bx
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xor bx,bx
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xor cx,cx
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mov di,bp
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push ss
110+
pop es
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mov ax,0301h ;temporarily switch to real-mode
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int 31h
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call printstring
115+
db "back in protected-mode",CR,LF,0
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mov ax, 4C00h ;normal client exit
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int 21h
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119+
backinreal:
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push cs
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pop ds
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call printstring
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db "switched to real-mode",CR,LF,0
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retf ;back to protected-mode
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126+
;--- print a string in both protected-mode and real-mode.
127+
;--- uses simple DOS commands without pointers.
128+
129+
printstring:
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pop si
131+
nextchar:
132+
lodsb
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and al,al
134+
jz stringdone
135+
mov dl,al
136+
mov ah,2
137+
int 21h
138+
jmp nextchar
139+
stringdone:
140+
push si
141+
ret
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143+
end start

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