Emulator 8086 :
Konversi Assembler Kode
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Ketik kodenya di teks
area dan klik [Compile]. Kemudian tentukan tempat penyimpanan filenya. Setelah
berhasil, klik [Emulate] untuk meload filenya kedalam emulator.
Direktori File Keluaran:
#MAKE_COM#
#MAKE_BIN#
#MAKE_BOOT#
#MAKE_EXE# You can insert these directives in the source code
to specify the required output type for the file. Only if compiler cannot find
any of these directives it will ask you for output type before creating
the file.
Description of Output File Types:
- #MAKE_COM# - the oldest and the simplest format of an executable
file, such files are loaded with 100h prefix (256 bytes). Select Clean
from the New menu if you plan to compile a COM file. Compiler directive
ORG 100h should be added before the code. Execution always starts from
the first byte of the file.
Supported by DOS and Windows Command Prompt.
- #MAKE_EXE# - more advanced format of an executable file. Not
limited by size and number of segments. Stack segment should be defined in the
program. You may select EXE Template from the New menu in to
create a simple EXE program with defined Data, Stack, and Code
segments.
Entry point (where execution starts) is defined by a
programmer.
Supported by DOS and Windows Command Prompt.
- #MAKE_BIN# - a simple executable file. You can define the values of
all registers, segment and offset for memory area where this file will be
loaded. When loading "MY.BIN" file to emulator it will look for a
"MY.BINF" file, and load "MY.BIN" file to location specified in
"MY.BINF" file, registers are also set using information in that file
(open this file in a text editor to edit or investigate).
In case emulator
is not able to find "MY.BINF" file, current register values are used
and "MY.BIN" file is loaded at current CS:IP.
Execution
starts from values in CS:IP.
This file type is unique to
Emu8086 emulator.
".BINF file is created
automatically by compiler if it finds #MAKE_BIN# directive.
WARNING! any existing ".binf" file is overwritten!
#LOAD_SEGMENT=1234#
#LOAD_OFFSET=0000#
#AL=12#
#AH=34#
#BH=00#
#BL=00#
#CH=00#
#CL=00#
#DH=00#
#DL=00#
#DS=0000#
#ES=0000#
#SI=0000#
#DI=0000#
#BP=0000#
#CS=1234#
#IP=0000#
#SS=0000#
#SP=0000# |
Values must be in
HEX!
When not specified these values are set by default:
LOAD_SEGMENT = 0100
LOAD_OFFSET = 0000
CS =
ES = SS = DS = 0100
IP = 0000
If
LOAD_SEGMENT and LOAD_OFFSET are not defined, then CS and
IP values are used and vice-versa.
In
case Load to offset value is not zero (0000), ORG ????h should
be added to the source of a .BIN file where ????h is the
loading offset, this should be done to allow compiler calculate correct
addresses.
- #MAKE_BOOT# - this type is a copy of the first track of a floppy
disk (boot sector).
You can write a boot sector of a virtual floppy
(FLOPPY_0) via menu in emulator:
[Virtual Drive] -> [Write 512 bytes
at 7C00 to Boot Sector]
First you should compile a ".boot" file
and load it in emulator (see "micro-os_loader.asm" and
"micro-os_kernel.asm" in "Samples" for more info).
Then select
[Virtual Drive] -> [Boot from Floppy] menu to boot emulator from a
virtual floppy.
Then, if you are curious, you may write the virtual
floppy to real floppy and boot your computer from it, I recommend using
"
RawWrite for Windows"
(note
that "micro-os_loader.asm" is not using MS-DOS compatible boot sector,
so it's better to use and empty floppy, although it should be IBM (MS-DOS)
formatted).
Compiler directive ORG 7C00h should be added before the
code, when computer starts it loads first track of a floppy disk at the
address 0000:7C00.
The size of a .BOOT file should be less then 512
bytes (limited by the size of a disk sector).
Execution always starts from
the first byte of the file.
This file type is unique to Emu8086
emulator.
Error Processing
Compiler reports about errors in a separate
information window:
MOV DS, 100 - is illegal instruction because segment
registers cannot be set directly, general purpose register should be
used:
MOV AX, 100
MOV DS, AX
MOV AL, 300 - is illegal instruction because AL
register has only 8 bits, and thus maximum value for it is 255 (or 11111111b),
and the minimum is -128.
Compiler makes several passes before generating the correct machine code, if
it finds an error and does not complete the required number of passes it may
show incorrect error messages. For example: #make_COM#
ORG 100h
MOV AX, 0
MOV CX, 5
m1: INC AX
LOOP m1 ; not a real error!
MOV AL, 0FFFFh ; error is here.
RET List of generated
errors:
(7) Condition Jump out of range!: LOOP m1
(9) Wrong parameters:
MOV AL, 0FFFFh
(9) Operands do not match: Second operand is over 8 bits!
First error message (7) is incorrect, compiler did not finish
calculating the offsets for labels, so it presumes that the offset of m1
label is 0000, that address is out of the range because we start at
offset 100h.
Make correction to this line: MOV AL, 0FFFFh
(AL cannot hold 0FFFFh value). This fixes both errors! For example:
#make_COM#
ORG 100h
MOV AX, 0
MOV CX, 5
m1: INC AX
LOOP m1 ; same code no error!
MOV AL, 0FFh ; fixed!
RET
ketika menyimpan file kompilasi, kompiler juga menyimpan 2 file yang juga digunakan
oleh Emulator untuk menampilkan data ketika dijalankan dan mengkoreksi tiap baris.
- *.~asm - file ini merupakan source kode asli yang digunakan untuk membuat
file exe.
- *.debug - this file has information that enables the emulator
select lines of original source code while running the machine code.
- *.symbol - Symbol Table, it contains information that enables to
show the "Variables" window. It is a text file, so you may view it in any text
editor.
- *.binf - this file contains information that is used by emulator to
load BIN file at specified location, and set register values prior execution;
(created only if an executable is a BIN file).
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