A. APPENDIX: ASSEMBLER DIRECTIVES AND NAMING RULES š

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A. APPENDIX: ASSEMBLER DIRECTIVES AND
NAMING RULES
SECTION A.1: 80x86 ASSEMBLER DIRECTIVES
This section consists of two parts. The first part describes some of the most widely used directives in 80x86
Assembly language programming. In the second part Assembly language rules and restrictions for names
and labels are discussed and a list of reserved words is provided.
Directives, or as they are sometimes called, pseudo-ops or pseudo-instructions, are used by the assembler to
help it translate Assembly language programs into machine language. Unlike the microprocessor's
instructions, directives do not generate any opcode; therefore, no memory locations are occupied by
directives in the final ready-to-run (exe) version of the assemblly program. To summarize, directives give
directions to the assembler program to tell it how to generate the machine code; instructions are assembled
into machine code to give directions to the CPU at execution time. The following are descriptions of the
some of the most widely used directives for the 80x86 assembler. They are given in alphabetical order for
ease of reference.
ASSUME
The ASSUME directive is used by the assembler to associate a given segment's name with a segment
register. This is needed for instructions that must compute an address by combining an offset with a segment
register. One ASSUME directive can be used to associate all the segment registers. For example:
ASSUME CS:name1,DS:name2,SS:name3,ES:name4.
where name1, name2, and so on, are the names of the segments. The same result can be achieved by having
one ASSUME for each register:
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ASSUME CS:name1
ASSUME DS:name2
ASSUME SS:name3
ASSUME ES:nothing
ASSUME nothing
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The key word "nothing" can be used to cancel a previous ASSUME directive.
DB (Define Byte)
The DB directive is used to allocate memory in byte-sized increments. Look at the following examples:
DATA1 DB 23
DATA2 DB 45,97h,10000011b
DATA3 DB 'The planet Earth'
In DATA1 a single byte is defined with initial value 23, DATA2 consists of several values in decimal (45),
hex (97H), and binary (10000011B), Finally, in DATA3, the DB directive is used to define ASCII
characters. The DB directive is normally used to define ASCII data. In all the examples above, the address
location for each value is assigned by the assembler. We can assigned a specific offset address by the use of
the ORG directive.
DD (Define Doubleword)
To allocate memory in 4-byte (32-bit) increments, the DD directive is used. Since word-sized operands are
16 bits wide (2 bytes) in 80x86 assemblers, a doubleword is 4 bytes.
VALUE1 DD 4563F57H
RESULT DD ? ; RESERVE 4-BYTE LOCATION
DAT4 DD 25000000
It must be noted that the valules defined using the DD directive are placed in memory by the assembler in
low byte to low address and high byte to high address order. This convention is referred to as little endian.
For example, asssuming that offset address 0020 is assigned to VALUE1 in the example above, each byte
will reside in memory as follows:
DS:20=(57)
DS:21=(3F)
DS:22=(56)
DS:23=(04)
DQ (Define Quadword)
To allocate memory in 8-byte increments, the DQ directive is used. In the 80x86 a word is defined as 2
bytes; therefore, a quadword is 8 bytes.
DAT_64B DQ 5677DD4EE4FF45AH
DAT8 DQ 10000000000000
DT (Define Tenbytes)
To allocate packed BCD data, 10 bytes at a time, the DT directive is used. This is widely used for memory
allocation associated with BCD numbers.

DATA DT 39997765419974
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Notice there is no H for the hexadecimal identifier following the number. This is a characteristic particular
to the DT directive. In the case of other directives (DB, DW, DD, DQ), if there is no H at the end of the
number, it is assumed to be in decimal and will be converted to hex by the assembler. Remember that the
little endian convention is used to place the bytes in memory, with the least significant byte going to the low
address and the most significant byte to the high address. DT can also be used to allocated decimal data if
"d" is placed after the number.
DATA DT 6553d ; stores hex FFFF in a 10-byte location
DUP (Duplicate)
The DUP directive can be used to duplicate a set of data a certain number of times instead of having to write
it over and over.
DATA1 DB 20 DUP(99) ; DUPLICATE 99 20 TIMES
DATA2 DW 6 DUP(5555H) ; DUPLICATE 5555H 6 TIMES
DATA3 DB 10 DUP(?) ; RESERVE 10 BYTES
DATA4 DB 5 DUP(5 DUP(0)) ; 25 BYTES INITIALIZED TO ZERO
DATA5 DB 10 DUP(00,FFH) ; 20 BYTES ALTERNATE 00, FF
DW (Define Word)
To allocate memory in 2-byte (16-bit) increments, the DW dirctive is used. In the 80x86 family, a word is
defined as 16 bits.
DATAW_1 DW 5000
DATAW_2 DW 7F6Bh
Again in terms of placing the bytes in memory the little endian convention is used with the least significant
byte giong to the low address and the most significant byte going to the high address.
END
Every program must have an entry point. To identify that entry point the assembler relies on the END
directive. The label for the entry and end point must match.
HERE: MOV AX,DATASEG ;ENTRY POINT OF THE PROGRAM
. . .
END HERE ; EXIT POINT OF THE PROGRAM
If there are several modules, only one of them can have the entry point, and the name of that entry point
must be the same as the name put for the END directive as shown below:
; from the main program:
EXTRN PROG1:NEAR
....
MAIN_PRO: MOV AX,DATASG ; THE ENTRY POINT
MOV DS,AX
....
CALL PROG1
....
END MAIN_PRO ;THE EXIT POINT
; from the module PROG1:
PUBLIC PROG1
PROG1 PROC
...
RET ; RETURN TO THE MAIN MODULE
PROG1 ENDP
END ; NO LABELIS GIVEN
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- Notice the following points about the above code:
1. The entry point must be identified by a name. In the example above the entry point is identified by the
name MAIN_PRO.
2. The exit point must be identified by the same name given to the entry p oint, MAIN_PRO.
3. Since a given program can have only one entry point and exit point, all modules called (either from main
or from the submodules) must have directive END with nothing after it.
ENDP (see the PROC directive)
ENDS (see the SEGMENT and STRUCT directives)
EQU (Equate)
To assign a fixed value to a name, one uses the EQU directive. The assembler will replace each occurrence
of the name with the value assigned to it.
FOX_VALU EQU 1200
PORT_A EQU 60H
COUNT EQU 100
MASK_1 EQU 00001111B
Unlike data directives such as DB, DW, and so on, EQU does not assign any memory storage: therefore, it
can be defined at any time at any place, and can even be used within the code segment.
EVEN
The EVEN directive forces memory allocation to start at an even addr ess. This is useful due to the fact that
in 8086, 286,, and 386SX microprocessors, accessing a 2-byte operand located at an odd address takes extra
time. The use of the EVEN directive directs the assembler to assign an even address to the variable.
ORG 0020H
DATA_1 DB 34H
EVEN
DATA_2 DW 7F5BH
The following shows the contents of memory locations:
DS:0020 = (34)
DS:0021 = (?)
DS:0022 = (5B)
DS:0023 = (7F)
EXTRN (External)
The EXTRN directive is used to indicate that certain variables and names used in module are defined by
another module. In the absence of the EXTRN directive, the assembler would search for the definition and
give an error when it couldn’t find it. The format of this directive is:
EXTRN name1:typea [,name2:typeb]
where type will be NEAR or FAR if name refers to a procedure, or will be BYTE, WORD, DWORD,
QWORD, TBYTE if name refers to a data variable.
;from the main program:
EXTRN PROG1:NEAR
PUBLIC DATA1
. . .

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MAIN_PRO MOV AX,DATASG ; THE ENTRY POINT
MOV DS,AX
. . .
CALL PROG1
. . .
END MAIN_PRO ; THE EXIT POINT
; PROG1 is located in a different file:
PROG1 PROC
EXTRN DATA1:WORD
PUBLIC PROG1
. . .
MOV BX,DATA1
. . .
RET
PROG1 ENDP
END
Notice that EXTRN directive is used in the main procedure to identify PROG1 as a NEAR procedure. This
is needed because PROG1 is not defined in that module. Correspondingly, PROG1 is defined as PUBLIC in
the module where it is defined. EXTRN is used in the PROG1 module to declare that operand DATA1, of
size WORD, has been defined in another module. Correspondingly, DATA1 is declared as PUBLIC in the
calling module.
GROUP
The GROUP directive causes the named segments to be linked into the same 64k bytes. This can be used to
combine segments of the same type, or different classes of segments. An example follows:
SMALL_SYS GROUP DTSEG,STSEG,CDSEG
The ASSUME directive must be changed to make the segment registers point to the group:
ASSUME CS:SMALL_SYS,DS:SMALL_SYS,SS:SMALL_SYS
The group will be listed in the list file, as shown below:
Name Lenght Align Combine Class
SMALL_SYS GROUP
STSEG 0040 PARA NONE
DTSEG 0024 PARA NONE
CDSEG 005A PARA NONE
INCLUDE
When there is a group of macros written and saved in a separate file, the INCLUDE directive can be used to
bring them into another file.In the program listing (.Ist file), these macros will be identified by the symbol
“C” (or “+” in some versions of MASM) before each instruction to indicate that they are copied to the
present file by the INCLUDE directive.
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LABEL
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The LABEL directive allows a given variable or name to be referred to by multiple names.This is often used
for multiple definition of the same variable or name. The format of the LABEL directive is
name LABEL type
where type may be BYTE, WORD, DWORD, QWORD. For example, a variable name DATA1 is defined
as a word and also needs to be accessed as 2 bytes, as shown in the following:
DATA_B LABEL BYTE
DATA1 DW 25F6H
MOV AX,DATA1 ;AX=25F6H
MOV BL,DATA_B ;BL-F6H
MOV BH,DATA_B+1 ;BH=25H
The following shows the LABEL directive being used to allow accessing a 32-bit data item in 16-bit
portions.
DATA_16 LABEL WORD
DATDD_4 DD 4387983FH
....
MOV AX,DATA_16 ;AX=983FH
MOV DX,DATA_16+2 ;DX=4387H
The following shows its use in a JMP instruction to go to a different code segment
...
JMP PROG_A
PROG_A LABEL FAR
INITI: MOV AL,12H
OUT PORT,AL
In the program above the address assigned to the names “PROG_A” and “INITI” are exactly the same. The
same function can be achieved by the following.
JMP FAR PTR INITI
LENGHT
The LENGTH operator returns the number of items defined by a DUP operand. See the SIZE directive for
an example.
OFFSET
To access the offset address assigned to a variable or a name, one uses the OFFSET directive. For example,
the OFFSET directive was used in the following example to get the offset address assigned by the assembler
to the variable DATA1:
ORG 5600H
DATA1 DW 2345H
...
MOV SI,OFFSET DATA1 ; SI=OFFSET OF DATA1 = 5600H
Notice that this has the same result as “LEA SI.DATA1”
ORG (Origin)
The ORG directive is used to assign an offset address for a variable or name. For example, to force variable
DATA1 to be located starting from offset address 0020, one would write
ORG 0020H
DATA1 DW 41F2H
This ensures the offset addresses of 0020 and 0021 with contents 0020H = (F2) and 0021H = (41).
PAGE

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The PAGE directive is used to make the “.Ist” file print in a specific format. The formaat of the PAGE
directive is
PAGE [lines],[columns]
The default listing (meaning that no PAGE directive is coded) will have 66 lines per page with a maximum
of 80 characters per line.This can be changed to 60 and 132 with the directive “PAGE 60, 132”. The range
for number of lines is 10 to 255 and for columns is 60 to 132. A PAGE directive with no number will
generate a page break.
PROC and ENDP (Procedure and End Procedure)
Often, a group of Assembly language instructions will be combined into a procedure so that it can be called
by another module. The PROC and ENDP directives are used to indicate the beginning and end of the
procedure.For a given procedure the name assigned to PROC and ENDP must be exactly the same.
name1 PROC [attribute]
....
name1 ENDP
There are two choices fo the attrribute of the PROC: NEAR or FAR. If no attribute is given, the default is
NEAR. When a NEAR procedure is called, only IP is saved since CS of the called procedure is the same as
the calling program. If a FAR procedure is called, both IP and CS are saved since the code segment of the
called procedure is different from the calling program.
PTR (Pointer)
The PTR directive is used to specify the size of the operand. Among the options for size are BYTE, WORD,
DWORD, and QWORD. This directive is used in many different ways, the most common of which are
explained below.
1.PTR can be used to allow an override of a previously defined data directive.
DATA1 DB 23H,7FH,99H,0B2H
DATA2 DW 67F1H
DATA3 DD 22229999H
...
MOV AX,WORD PTR DATA1 ; AX=7F23
MOV BX,WORD PTR DATA1+2 ;BX, B299H
Although DATA1 was initially defined as DB, it can be accessed using the WORD PTR directive.
MOV AL,BYTE PTR DATA2 ;AL=F1H
In the above code, notice that DATA2 was defined as WORD but it was accessed as BYTE with the help of
BYTE PTR. If this had been coded as “MOV AL,DATA2”, it would generate an error since the sizes of the
operands do not match.
MOV AX,WORD PTR DATA3 ; AX=9999H
MOV DX,WORD PTR DATA3+2 ;DX,2222H
DATA3 was defined as a 4-byte operand but registers are only 2 bytes wide. The WORD PTR directive
solved that poroblem.
2. The PTR directive can be used to specify the size of a directive in order to help the assembler translate the
instruction.
INC [DI] ; will cause an error
This instruction was meant to increment the contents of the memory location(s) pointed at by [DI]. How
does the assembler know whether it is a byte operand, word operand, or doubleword operand? Since it does
not know, it will generate an error. To correct that, use the PTR directive to specify the size of the operand
as shown next.
INC BYTE PTR [SI] ; increment a byte pointed by SI
or
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INC WORD PTR [SI] ; increment a word pointed by SI
or
INC DWORD PTR [SI] ; increment a doubleword pointed by SI
3. The PTR directive can be used to specify the distance of a jump. The options for the distance are FAR
and NEAR.
JMP FAR PTR INTI ; ensures that it will be a 5-byte instruction
INTI MOV AX,1200
See the LABEL directive to find out how it can be used to achieve the same result.
PUBLIC
To inform the assembler that a name or symbol will be referenced by other modules, it is marked by the
PUBLIC directive. If a module is referencing a variable outside itself, that variable must be declared as
EXTRN. Correspondingly, in the module where the variable is defined, that variable must be declar ed as
PUBLIC in order to allow it to be referenced by other modules. See the EXTRN directive for examples of
the use of toth EXTRN and PUBLIC.
SEG (Segment Address)
The SEG operator is used to access the address of the segment where the name has been defin ed.
DATA1 DW 2341H
...
MOV AX,SEG DATA1 ;AX =SEGMENT ADDRESS OF DATA1
This is in contrast to the OFFSET directive, which accesses the offset address instead of the segment.
SEGMENT and ENDS
In full segment definition these two directives are used to indicate the beginning and the end of the
segment. They must have the same name for a given segment definition. See the following example:
DATSEG SEGMENT
DATA1 DB 2FH
DATA2 DW 1200
DATA3 DD 99999999H
DATSEG ENDS
There are several option associated with the SEGMENT directive, as follows:
name1 SEGMENT [align][combine][class]
name 1 ENDS
ALIGNMENT: When several assembled modules are linked togother, this indicates where the segment is to
begin. There are many options, including PARA (paragraph = 16 bytes), WORD, and BYTE. If PARA is
chosen, the segment starts at a hex address divisible by 10h, PARA is the default alignment. In this
alignment, if a segment for a module finished at 00024H, the next segment will start at address 00030H,
leaving from 00025 to 0002F unused. If WORD is chosen, the segment is forced to start at a word boundary.
In BYTE alignment, the segment starts at the next byte and no memory is wasted.There is also the PAGE
option, which aligns segments along the 100H (256) byte boundary. While all these options are supportes
by many assemblers, such as MASM and TASM, there is another option supported only by assemblers that
allow system development. This option is AT. The AT option allows the program to assign a physical
address. For example, to burn a program int ROM startilng at physical address F0000, code
ROM_CODE SEGMENT AT F000H
Due to the fact that option AT allows the programmer to specify a physical address that conflicts with
DOS’s memory management responsibility, many assemblers such as MASM will not allow option AT.
COMBINE TYPE: This option is used to merge together all the similar segment to create one large segment.
Among the options widely used are PUBLIC and STACK. PUBLIC is widely used in code segment

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definitions when linking more than one module. This will consolidate all the code segments of the various
modules into one large code segment. If there is only one data segment and that belongs to the main
module, there is no need to define it as PUBLIC since no other module has any data segment to combie
with. However, if other modules have their own data segments it is recommended that they be made
PUBLIC to create a single data segment when they are linked. In the absence of that, the llinker would
assume that each segment is private and they would not be combined with other similar segment (codes with
codes and data with data). Since there is only one stack segment, which belongs to the main module, there is
no need to define it as PUBLIC. The STACK option is used only with the stack segment definition and
indicates to the linker that it should combine the user’s defined stack with the system stack to create a single
stack for the entire program. This is the stack that is used at run time (when the CPU is actually ex ecuting
the program).
CLASS NAME: Indicates to the linker that all segments of the same class should be placed next to each
other by the LINKER. Four class names commonly used are “CODE”, “DATA”, “STACK”, and “EXTRA”.
When this attribute is used in the segment definition, it must be enclosed in single apostrophes in order to be
recognized by the linker.
SHORT
In a direct jump such as “JMP POINT_A”, the ssembler has to choose either the 2-byte or 3-byte format. In
the 2-bylte format, one byte is the opcode and the second byte is the signed number displacement value
added to the IP of the instruction immediately following the JMP. This displacement can be anywhere
between -128 and + 127. A negative number indicates a backward JMP and a positive number a forward
JMP. In the 3-bylte format the first byte is the opcode and the next two bytes are for the signed number
displacement value, which can range from -32,768 to 32,767. When assembling a program, the assembler
makes two passes through the program. Certain tasks are done in the first pass and orhers are left to the
second pass to complete. In the first pass the assembler choses the 3-bylte code for the JMP. After the first
pass is complete, it will know the target address and fill it in during the second pass. If the target address
indicates a short jump (less than 128) bytes away, it fills the last byte with NOP. To inform the assembler
that the target address is no more than 128 bytes away, the SHORT directive can be used. Using the SHORT
directive makes sure that the JMP is a 2-byte instructin and not 3-byte with 1 byte as NOP code. The 2-byte
JMP requires 1 byte less memory and is executed faster.
SIZE
The size opeator returns the total number of bytes occupied by a name. The three directives LENGTH,
SIZE, and TYPE are somewhat related.Below is a description of each one using the following set of data
defined in a data segment.:
DATA1 DQ ?
DATA2 DW ?
DATA3 DB 20 DUP (?)
DATA4 DW 100 DUP (?)
DATA5 DD 10 DUP (?)
TYPE allows one to know the storage allocation directive for a given variable by providing the number of
bytes according to the following table:
bytes
For example,
1 DB
2 DW
4 DD
8 DQ
10 DT
MOV BX,TYPE DATA2 ; BX=2
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MOV DX,TYPE DATA1 ; DX=8
MOV AX,TYPE DATA3 ; AX=1
MOV CX,TYPE DATA5 ; CX=4
When a DUP is used to define the number of entries for a given variable, the LENGTH directive can be
used to get that number.
MOV CX,LENGTH DATA4 ; CX = 64H (100 DECIMAL)
MOV AX,LENGTH DATA3 ; AX = 14H (20 DECIMAL)
MOV DX,LENGTH DATA5 ; DX = 0A (10 DECIMAL)
If the defined variable does not have any DUP in it, the LENGTH is assumed to be 1.
MOV BX,LENGTH DATA1 ; BX = 1
SIZE is used to determine the total number of bytes allocated for a variable that has been defined with the
DUP directive. In reallity the SIZE directive basically provides the product of the TYPE times LENGTH.
MOV DX,SIZE DATA4 ; DX = C8H = 200 (100 * 2 = 200)
MOV CX,SIZE DATA5 ; CX = 28H = 40 (4 * 10 = 40)
STRUC (Structure)
The STRUC directive indicates the beginning of a structure definition. It ends with an ENDS directive,
whose label matches the STRUC label. Althuogh the same mnemonic END is used for end of segment and
end of structurre, the assembler knows which is meant by the context. A structure is a collection of dat sa
types that can be accessed either collectively by the structure name or individually by the labels of the data
types within the structure. A structure type must first be defined and then variables in the data segment may
be allocated as that structure type. Looking at the following example, the data directives between STRUC
and ENDS declare what structure ASC_AREA looks like. No memory is allocated for such a structure
definition. Immediately below the structure definition is the label ASC_INPUT, which is declared to be of
type ASC_AREA. Memory is allocated for the variable ASC_INPUT. Notice in the code segment that
ASC_INPUT can be accessed either in its entirety or by its component parts. It is accessed as a whole unit in
“MOV DX,OFFSET ASC_INPUT”. Its component parts are accessed by the variable name followed by a
period, then the component’s name. For example, “MOV BL,ASC_INPUT.ACT_LEN” accesses the actual
length field of ASC_INPUT.
;from the data segment:
ASC_AREA STRUC ; defines struc for string input
MAX_LEN DB 6 ; maximum length of input string
ACT_LEN DB ? ; actual length of input string
ASC_NUM DB 6 DUP(?) ; input string
ASC_AREA ENDS ; end struc definition
ASC_INPUT ASC_AREA ; allocates memory for struc
; from the code segment:
GET_ASC: MOV AH,0AH
MOV DX,OFFSET ASC_INPUT
INT 2H
...
MOV SI,OFFSET ASC_INPUT.ASC_NUM ; SI points to ASCII num
MOV BL,ASC_INPUT.ACT_LEN ; BL holds string length
...
TITLE
The TITLE directive instructs the assembler to print the title of the program on top of each page of the
“.lst” file. What comes after the TITLE pseudo-instruction is up to the programmer, but it is common
practice to put the name of the program as stored on the disk right after the TITLE pseudo -instruction and
then a brief description of the function of the program. Whatever is placed after the TITLE pseudo -
instruction cannot be more than 60 ASCII characters (letters, numbers, spaces, punctuation).

TYPE
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The TYPE operator returns the number of bytes reserved for the named data object. See the SIZE directive
for examples of its use.
SECTIN A.2: RULES FOR LABELS AND RESERVED NAMES
Labels in 80x86 Assembly language for MASM 5.1 and higher must follow these rules:
1. Names can be composed of:
alphabetic characters: A - Z and a - z
digits: 0 - 9
special characters. “?” “.” “@”” “_” “$”
2. Names must begin with an alphabetic or special character. Names cannot begin with a digit.
3. Names can be up to 31 characters long.
4. The special character “.” can only be used as the first character.
5. Uppercase and lowercase are treated the same. “NAME1” is treated the same as “Name1” and “name1”.
Assembly language programs have five types of labels of names:
1. Code labels, which give symbolic names to instructions so that oth er instructins (such as jumps) may refer
to them
2. Procedure labels, which assign a name to a procedure
3. Segment labels, which assign a name to a segment
4. Data labels, which give names to data items
5. Labels created with the LABEL directive
Code labels
These labels will be followed by a colon and have the type NEAR. This enables other instructions within the
code segment to refer to the instruction. The labels can be on the same line as the instruction:
ADD_LP: ADD AL,[BX] ; label is on same line as the instruction
...
...
LOOP ADD_LP
or on a line by themselves:
ADD_LP: ; label is on a line by itself
ADD AL,[BX] ; ADD_LP refers to this instruction
...
....
LOOP ADD_LP
Procedure labels
These labels assign a symbolic name to a procedure.The label can be NEAR or FAR. When using full
segment definition, the default type is NEAR. When using simplified segment definition, the type will be
NEAR for compact or small models but will be FAR for medium, large,and huge models. For more
information on procedures, see PROC in Section A.1.
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Segment labels
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These labels give symbolic names to segments. The name must be the same in the SEGMENT and ENDS
directives.See SEGMENT in Section A.1 for more information. Example:
DAT_SG SEGMENT
SUM DW ?
DAT_SG ENDS
Data labels
These labels give symbolic names to data items. This allows them to be accessed by instructions.Directives
DB, DW, DD, DQ, and DT are used to allocate data. Examples:
DATA1 DB 43H
DATA2 DB F2H
SUM DW ?
Labels defined with the LABEL directive
The LABEL directive can be used to redefine a label. See LABEL in Section A.1 for more information.
Reserved Names
The following is a list of reserved words in 80x86 Assembly language programming. These words cannot be
used as user-defined labels or variable names.
Register Names:
AH AL AX BH BL BP BX CH CL CS CX DH
DI DL DS DX ES SI SP SS
Instructions:
AAA AAD AAM AAS ADC ADD
AND CALL CBW CLC CLD CLI
CMC CMP CMPS CWD DAA DAS
DEC DIV ESC HLT IDIV IMUL
IN INC INT INTO IRET JA
JAE JB JBE JCXZ JE JG
JGE JL JLE JMP JNA JNAE
JNB JNBE JNE JNG JNGE JNL
JNLE JNO JNP JNS JNZ JO
JP JPE JPO JS JZ LAHF
LDS LEA LES LOCK LODS LOOP
LOOPE LOOPNE LOOPNZ LOOPZ MOV MOVS
MUL NEG NIL NOP NOT OR
OUT POP POPF PUSH PUSHF RCL
RCR REP REPE REPNE REPNZ REPZ
RET ROL ROR SAHF SAL SAR
SBB SCAS SHL SHR STC STD

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STI STOS SUB TEST WAIT XCHG
XLAT XOR
Assembler operators and directives
$ * + - . / = ? [ ]
ALIGN ASSUME BYTE COMM COMMENT DB
DD DF DOSSEG DQ DS DT
DW DWORD DUP ELSE END ENDIF
ENDM ENDS EQ EQU EVEN EXITM
EXTRN FAR FWORD GE GROUP GT
HIGH IF IFB IFDEF IFDIF IFE
IFIDN IFNB IFNDEF IF1 IF2 INCLUDE
INCLUDELI
B
IRP IRPC LABEL LE LENGTH
LINE LOCAL LOW LT MACRO MASK
MOD NAME NE NEAR NOTHING OFFSET
ORG PAGE PROC PTR PUBLIC PURGE
QWORD RECORD REPT REPTRD SEG SEGMENT
SHORT SIZE STACK STRUC SUBTTL TBYTE
THIS TITLE TYPE WIDTH WORD
.186 .286 .286P .287 .386 .386P
.387 .8086 .8087 .ALPHA .CODE .CONST
.CREF .DATA .DATA? .ERR .ERR1 .ERR2
.ERRB .ERRDEF .ERRDIF .ERRE .ERRIDN .ERRNB
.ERRNDEF .ERRNZ .FARDATA .FARDATA? .LALL .LFCOND
.LIST .MODEL %OUT .RADIX .SALL .SEQ
.SFCOND .STACK .TECOND .TYPE .XALL .XCREF
.XLIST
A-13

A.3 The instruction set
A-14
Zbirka zadataka iz Mikroprocesora i mikrora~unara
The instruction set summary contains a complete alphabetical listing of the entire 8086 --Pentium Pro
instruction set.
Each instruction entry lists the mnemonic opcode plus a brief description of the purpose of the instruction.
Also listed is the binary machine language coding of each instruction, plus any other data required to form
the instruction, such as the displacement or immediate data. Listed to the right of each binary machine
language version of the instruction are the flag bits and any change that might occur for the instruction. The
flags are described in the following manner: a blank indicates no effect or change, a ? indicates a change
with an unpredictable outcome, a * indicates a change with a predictable outcome, a 1 indicates that the flag
is set, and a 0 indicates that the flag is cleared. If the flag bits ODITSZAPC are not illustrated with an
instruction does not modify any of these flags.
Before the instruction listing begins, some information about the bit settings in binary machine language
versions of the instructions is presented. Table A-1 lists the modifier bits, coded as oo in the instruction
listings.
Table A-2 lists the memory-addressing modes available using a register field coding of mmm. This table
applies to all versions of the microprocessor as long as the operating mode is 16 -bits.
Table A-3 lists the register selections provided by the rrr field in an instruction. This table includes the
register selections for 8-, 16-, and 32-bit registers.
'TABLE A-1 The modifier bits, coded as oo in the instruction listing
oo Function
00 If mmm = 110, then a displacement follows the opcode; otherwise, no displacement is used
01 An 8-bit signed displacement follows the opcode
10 A 16-bit signed displacement follows the opcode (unless it is a 32 -bit displacement)
11 mmm specifies a register instead of an addressing mode
TABLE A-2 The 16-bit register/memory (mmm) field description
mmm Function
000 DS:[BX+SI]
001 DS:[BX+DI]
010 SS:[BP+SI]
011 SS:[BP+DI]
100 DS:[SI]
101 DS:[DI]
110 SS:[BP]
111 DS:[BX]
TABLE A-3 The register field (rrr) assignment

Rrr W=0 W=1 (16-bit) W=1 (32-bit)
000 AL AX EAX
001 CL CX ECX
010 DL DX EDX
011 BL BX EBX
100 AH SP ESP
101 CH BP EBP
110 DH SI ESI
111 BH DI EDI
Dodatak A
Table A-4 lists the segment register bit assignment (rrr) found with the MOV, PUSH, and POP instructions.
When the 80386-Pentium Pro are used, some of the definitions provided in Tables A-1 through A-3 change.
Refer to Tables A-5 and A-6 for these changes as they apply to the 80386-Pentium Pro microprocessors.
TABLE A-4 Register field assignments (rrr) for the segment registers
rrr Segment Register
000 ES
001 CS
010 SS
011 DS
100 FS
101 GS
TABLE A-5 Index register specified with rrr for the advanced addressing mode found in the 80386-Pentium
Pro microprocessors
rrr Index Register
000 DS:[EAX]
001 DS:[ECX]
010 DS:[EDX]
011 DS:[EBX]
100 No index (see Table A-6)
101 SS:[EBP]
110 DS:[ESI]
111 DS:[EDI]
A-15

A-16
Zbirka zadataka iz Mikroprocesora i mikrora~unara
TABLE A-6 Possible combinations of oo, mmm, and rrr for the 80386-Pentium Pro microprocessors using
32-bit addressing
oo mmm rrr (base in scaled index byte) Addressing Mode
00 000 - DS:[EAX]
00 001 - DS:[ECX]
00 010 - DS:[EDX]
00 011 - DS:[EBX]
00 100 000 DS:[EAX+scaled index]
00 100 001 DS:[ECX+scaled index]
00 100 010 DS:[EDX+scaled index)
00 100 011 DS:[EBX+scaled index]
00 100 100 SS:[ESP+scaled index]
00 100 101 DS:[disp32+scaled index]
00 100 110 DS:[ESI+scaled index]
00 100 111 DS:[EDI+scaled index]
00 101 - DS:disp32
00 110 - DS:[ESI]
00 111 - DS:[EDI]
01 000 - DS:[EAX+disp8]
01 001 - DS:[ECX+disp8]
01 010 - DS:[EDX+disp8]
01 011 - DS:[EBX+disp8]
01 100 000 DS:[EAX+scaled index+disp8]
01 100 001 DS:[ECX+scaled index+disp8]
01 100 010 DS:[EDX+scaled index+disp8]
01 100 011 DS:[EBX+scaled index+disp8]
01 100 100 SS:[ESP+scaled index+disp8]
01 100 101 SS:[EBP+scaled index+disp8]
01 100 110 DS:[ESI+scaled index+disp8]
01 100 111 DS:[EDI+scaled index+disp8]
01 101 - SS:[EBP+disp8]
01 110 - DS:[ESI+disp8]
01 111 - DS:[EDI+disp8]
10 000 - DS:[EAX+disp32]
10 001 - DS:[ECX+disp32]
10 010 - DS:[EDX+disp32]
10 011 - DS:[EBX+disp32]
10 100 000 DS:[EAX+scaled lndex+d19p32]
10 100 001 DS:[ECX+scaled index+disp32]
10 100 010 DS:[EDX+scaled index+disp32]
10 100 011 DS:[EBX+scaled index+disp32]

Dodatak A
10 100 100 SS:[ESP+scaled index+disp32]
10 100 101 SS:[EBP+scaled index+disp32]
10 100 110 DS:[ESI+scaled index+disp32]
10 100 111 DS:[EDI+scaled index+disp32)
10 101 SS:[EBP+disp32]
10 110 DS:[ESI+disp32]
10 111 DS:[EDI+disp32]
Notes: disp8=8-bit displacement and disp32=32-bit displacement.
In order to use the scaled index addressing modes listed in Table A-6, code oo and mmm in the second byte
of the opcode. The scaled index byte is usually the third byte and contains three fields. The leftmost 2-bits
determine the scaling factor (00 = *1, 01 = *2, 10 = *4, or 11 – *8) The next three bits toward the right
contain the scaled index register number (this is obtained from Table A-5). The rightmost 3-bits are from the
rrr field listed in Table A-6 .For example, the MOV AL,[EBX+2*ECX] instruction has a scaled index byte
of 01 001 011 where 01 = *2, 001= ECX, and 011 = EBX.
Some instructions are prefixed to change the default segment or to override the mode. Table A-7 lists the
segment and instruction mode override prefixes with append at the beginning of an instruction if they are
used to form the instruction. For example, the MOV AL,ES:[BX] instruction uses the extra segment
because of the override prefix ES:. In the 8086 and 8088 microprocessors the effective address calculation
requires additional clocks that are added to the times in the instruction set summary. These additional times
are listed in Table A-8. No such times are added to the 80286-Pentium Pro. Note that Intel has not released
clock times for the Pentium Pro.
TABLE A7 Override prefixes
Prefix Eye Purpose
26H ES: segment override prefix
2EH CS: segment override prefix
36H SS: segment override prefix
3EH DS: segment override prefix
64H FS: segment override prefix
65H GS: segment override prefix
66H Operand size instruction mode override
67H Register size instruction mode override
TABLE A8 Effective address calculations for the 8086 and 8088 microprocessors
Type Clocks Example Instruction
Base or index 5 MOV CL,[DI]
Displacement 3 MOV AL,DATA1
Base plus index 7 MOV AL,[BP+SI]
Displacement plus base or index 9 MOV DH.[DI+20H]
Base plus index plus displacement 11 MOV CL,[BX+DI+2]
Segment override ea + 2 MOV AL,ED:[DI]
A-17

AAA ASCII adjust AL after addition
A-18
Zbirka zadataka iz Mikroprocesora i mikrora~unara
00110111 0 D I T S Z A P C
? ? ? * ? *
Example Microprocessor Clocks
AAA
AAD ASCII adjust AX before division
8086 8
8088 8
80286 3
80386 4
80486 3
Pentium 3
Pentium Pro
11010101 00001010 0 D I T S Z A P C
? * * ? * ?
Example Microprocessor Clocks
AAD
AAM ASCII adjust AX after multiplication
8086 60
8088 60
80286 14
80386 19
80486 14
Pentium 10
Pentium Pro
11010100 00001010 0 D I T S Z A P C
? * * ? * ?
Example Microprocessor Clocks
AAM
8086 83
8088 83
80286 16
80386 17
80486 15
Pentium 18
Pentium Pro

AAS ASCII adjust AL after subtraction
Dodatak A
00111111 O D I T S Z A P C
? ? ? * ? *
Example Microprocessor Clocks
AAS
ADC Addition with carry
8086 8
8088 8
80286 3
80386 4
80486 3
Pentium 3
Pentium Pro
00111111 O D I T S Z A P C
* * * * * *
Format Examples Microprocessor Clocks
ADC reg,reg
ADC mem,reg
ADC reg,mem
ADC AX,BX
ADC AL,BL
ADC EAX,EBX
ADC CX,SI
ADC ESI,EDI
ADC DATAY,AL
ADC LIST,SI
ADC DATA2[D1],CL
ADC [EAX],BL
ADC [EBX+2*ECX],EDX
ADC BL,DATA1
ADC SI,LIST1
ADC CL,DATA2[SI]
ADC CX,[ESI]
ADC ESI,[2*ECX]
8086 3
8088 3
80286 3
80386 3
80486 1
Pentium 1 or 3
Pentiurn Pro
8086 16 + ea
8088 24 + ea
80286 7
80386 7
80486 3
Pentium 1 or3
Pentium Pro
8086 9+ea
8088 13+ea
80286 7
80386 6
80486 2
Pentium 1 or2
Pentium Pro
A-19

100000sw oo010mmm disp data
A-20
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Format Examples Microprocessor Clocks
ADC reg,imm
ADC
mem,imm
ADC acc,imm
ADD Addition
ADC CX,3
ADC DI,1AH
ADC DL,34H
ADC EAX,12345
ADC CX,1234H
ADC DATA4,33
ADC LIST,'A'
ADC DATA3[DI],2
ADC BYTE PTR[EBX],3
ADC WORD PTR[DI],669H
ADC AX,3
ADC AL,1AH
ADC AH,34H
ADC EAX,2
ADC AL,'Z'
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1 or 3
Pentium Pro
Microprocessor Clocks
8086 17+ea
8088 23+ea
80286 7
80386 7
80486 3
Pentium 1 or 3
Pentium Pro
Microprocessor Clocks
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1
Pentium Pro
000000dw oorrrmmm disp O D I T S Z A P C
* * * * * *
Format Examples Microprocessor Clocks
ADD reg,reg
ADD AX,BX
ADD AL,BL
ADD EAX,EBX
ADD CX,SI
ADD ESI,EDI
8086 3
8088 3
80286 3
80386 3
80486 1
Pentium 1 or 3
Pentiurn Pro

ADD mem,reg
ADD reg,mem
ADD DATAY,AL
ADC LIST,SI
ADD DATA2[DI],CL
ADD [EAX],BL
ADD [EBX+2*ECX],EDX
ADD BL,DATA2
ADD SI,LIST3
ADD CL,DATA2[DI]
ADD CX,[EDI]
ADD ESI,[ECX+200H]
100000sw oo000mmm disp data
Format Examples
ADD reg,imm
ADD
mem,imm
ADD CX,3
ADD DI,1AH
ADD DL,34H
ADD EAX,1345H
ADD CX,1834H
ADD DATA4,33
ADD LIST,'A'
ADD DATA3[DI],2
ADD BYTE PTR[EBX],3
ADD WORD PTR[DI],669H
ADC acc,imm ADD AX,3
ADD AL,1AH
ADD AH,34H
ADD EAX,2
ADD AL,'Z'
Dodatak A
8086 16 + ea
8088 24 + ea
80286 7
80386 7
80486 3
Pentium 1 or3
Pentium Pro
8086 9+ea
8088 13+ea
80286 7
80386 6
80486 2
Pentium 1 or2
Pentium Pro
Microprocessor
8086 4
8088 4
80286 3
80386 2
80486 1
Clocks
Pentium 1 or 3
Pentium Pro
8086 17+ea
8088 23+ea
80286 7
80386 7
80486 3
Pentium 1 or 3
Pentium Pro
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1
A-21

AND Logical AND
A-22
Zbirka zadataka iz Mikroprocesora i mikrora~unara
001000dw oorrrmmm disp O D I T S Z A P C
0 * * ? * 0
Format Examples Microprocessor Clocks
AND reg,reg
AND mem,reg
AND reg,mem
AND CX,BX
AND DL,BL
AND ECX,EBX
AND BP,SI
AND EDX,EDI
AND BIT,AL
ANC LIST,DI
AND DATAZ[BX],CL
AND [EAX],BL
AND [ESI+2*ECX],EDX
AND BL,DATAW
AND SI,LIST
AND CL,DATAQ[SI]
AND CX,[EAX]
AND ESI,[ECX+43H]
100000sw oo100mmm disp data
8086 3
8088 3
80286 2
80386 3
80486 1
Pentium 1 or 3
Pentiurn Pro
8086 16 + ea
8088 24 + ea
80286 7
80386 7
80486 3
Pentium 1 or3
Pentium Pro
8086 9+ea
8088 13+ea
80286 7
80386 6
80486 2
Pentium 1 or2
Pentium Pro
Format Examples Microprocessor Clocks
AND reg,imm
AND BP,1
AND DI,10H
AND DL,34H
AND EBP,1345H
AND SP,1834H
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1 or 3
Pentium Pro

AND
mem,imm
AND acc,imm
Dodatak A
AND DATA4,33 8086 17+ea
AND LIST,'A' 8088 23+ea
AND DATA3[DI],2 80286 7
AND BYTE PTR[EBX],3 80386 7
AND DWORD PTR[DI],66H 80486 3
AND AX,3
AND AL,1AH
AND AH,34H
AND EAX,2
AND AL,'r'
ARPL Adjust requested privilege level
Pentium 1 or 3
Pentium Pro
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1
Pentium Pro
01100011 oorrrmmm disp O D I T S Z A P C
Format Examples Microprocessor Clocks
ARPL reg,reg
ARPL mem,reg
ARPL AX,BX
ARPL BX.SI
ARPL AX,DX
ARPL BX,AX
ARPL SI,DI
ARPL DATAY,AX
ARPL LIST,DI
ARPL DATA3[DI],CX
ARPL [EBX],AX
ARPL [EDX+4*ECX],BP
BOUND Check array against boundary
*
8086 -
8088 -
80286 10
80386 20
80486 9
Pentium 7
Pentiurn Pro
8086 -
8088 -
80286 11
80386 21
80486 19
Pentium 7
Pentium Pro
A-23

01100010 oorrrmmm disp
A-24
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Format Examples Microprocessor Clocks
BOUND
reg,mem
BOUND AX,BETS
BOUND
BP,LISTG
BOUND CX,DATAX
BOUND BX,[DI]
BOUND
SI,[BX+2]
BSF Bit scan forward
8086 -
8088 -
80286 13
80386 10
80486 7
Pentium 8
Pentium Pro
00001111 10111100 oorrrmmm disp O D I T S Z A P C
? ? * ? ? ?
Format Examples Microprocessor Clocks
BSF reg,reg
BSF reg,mem
BSF AX,BX
BSF BX.SI
BSF EAX,EDX
BSF EBX,EAX
BSF SI,DI
BSF AX,DATAY
BSF SI,LIST
BSR Bit scan reverse
BSF
CX,DATA3[DI]
BSF EAX,[EBX]
BSF EBP,[EDX+4*ECX]
8086 -
8088 -
80286 -
80386 10+3n
80486 6--42
Pentium 6--42
Pentium Pro
8086 -
8088
80286
80386 10+3n
80486 7--43
Pentium 6--43
Pentium Pro
00001111 10111101 oorrrmmm disp O D I T S Z A P C
? ? * ? ? ?
Format Examples Microprocessor Clocks

BSR reg,reg
BSR reg,mem
BSR AX,BX
BSR BX,SI
BSR EAX,EDX
BSR EBX,EAX
BSR SI,DI
BSR AX,DATAY
BSR SI,LIST
BSWAP Byte swap
00001111 11001rrr
BSR
CX,DATA3[DI]
BSR EAX,[EBXI
BSR EBP,[EDX+4*ECX]
Dodatak A
8086 -
8088 -
80286 -
80386 10+3n
80486 6--103
Pentium 7--71
Pentium Pro
8086 -
8088 -
80286 -
80386 10+3n
80486 7--104
Pentium 7--72
Pentium Pro
Format Examples Microprocessor Clocks
BSWAP reg32
BT Bit test
BSWAP EAX
BSWAP EBX
BSWAP EDX
BSWAP ECX
BSWAP ESI
00001111 10111010ool00mmm disp
data
8086 -
8088 -
80286 -
80386 -
80486 1
Pentium 1
Pentium Pro
O D I T S Z A P C
Format Examples Microprocessor Clocks
BT reg,imm8
BT AX,2
BT CX,4
BT BP,10H
BT CX,8
BT BX,2
8086 -
8088 -
80286 -
80386 3
80486 3
Pentium 4
Pentium Pro
*
A-25

BT mem,imm8
BT reg,reg
BT mem,reg
A-26
Zbirka zadataka iz Mikroprocesora i mikrora~unara
BT DATA1,2
BT LIST,2
BT DATA2[DII,3
BT [EAX],1
BT FROG,6
BT AX,CX
BT CX,DX
BT BP,AX
BT SI,CX
BT EAX,EBX
BT DATA4,AX
BT LIST,BX
BT
DATA3[DI],CX
BT [EBX],DX
BT [DI],DI
BTC Bit test and complement
00001111 10111010oo11mmm disp
data
8086 -
8088 -
80286 -
80386 6
80486 3
Pentium 4
Pentium Pro
8086 -
8088 -
80286 -
80386 3
80486 3
Pentium 4 or 9
Pentium Pro
8086 -
8088
80286 -
80386 12
80486 8
Pentium 4 or 9
Pentium Pro
O D I T S Z A P C
Format Examples Microprocessor Clocks
BTC reg,imm8
BTC AX,2
BTC CX,4
BTC BP,10H
BTC CX,8
BTC BX,2
8086 -
8088 -
80286 -
80386 6
80486 6
Pentium 7 or 8
Pentium Pro
*

BTC
mem,imm8
00001111 10111011 disp
BTC DATA1,2
BTC LIST,2
BTC DATA2[DII,3
BTC [EAX],1
BTC FROG,6
Dodatak A
8086 -
8088 -
80286 -
80386 7 or 8
80486 8
Pentium 8
Pentium Pro
Format Examples Microprocessor Clocks
BTC reg,reg
BTC mem,reg
BTC AX,CX
BTC CX,DX
BTC BP,AX
BTC SI,CX
BTC EAX,EBX
BTC DATA4,AX
BTC LIST,BX
BTC
DATA3[DI],CX
BTC [EBX],DX
BTC [DI],DI
BTR Bit test and reset
00001111 10111010oo110mmm disp
data
8086 -
8088 -
80286 -
80386 6
80486 6
Pentium 7 or 13
Pentium Pro
8086 -
8088 -
80286 -
80386 13
80486 13
Pentium 7 or 13
Pentium Pro
O D I T S Z A P C
Format Examples Microprocessor Clocks
BTR reg,imm8
BTR AX,2
BTR CX,4
BTR BP,10H
BTR CX,8
BTR BX,2
8086 -
8088 -
80286 -
80386 6
80486 6
Pentium 7 or 8
Pentium Pro
*
A-27

BTR
mem,imm8
00001111 10110011 disp
A-28
Zbirka zadataka iz Mikroprocesora i mikrora~unara
BTR DATA1,2
BTR LIST,2
BTR DATA2[DI],3
BTR [EAX],1
BTR FROG,6
8086 -
8088 -
80286 -
80386 8
80486 8
Pentium 7 or 8
Pentium Pro
Format Examples Microprocessor Clocks
BTR reg,reg
BTR mem,reg
BTS Bit test and set
BTR AX,CX
BTR CX,DX
BTR BP,AX
BTR SI,CX
BTR EAX,EBX
BTR DATA4,AX
BTR LIST,BX
BTR
DATA3[DI],CX
BTR [EBX],DX
BTR [DI],DI
00001111 10111010oo101mmm disp
data
8086 -
8088 -
80286 -
80386 6
80486 6
Pentium 7 or 13
Pentium Pro
8086 -
8088 -
80286 -
80386 13
80486 13
Pentium 7 or 13
Pentium Pro
O D I T S Z A P C
Format Examples Microprocessor Clocks
BTS reg,imm8
BTS AX,2
BTS CX,4
BTS BP,10H
BTS CX,8
BTS BX,2
8086 -
8088 -
80286 -
80386 6
80486 6
Pentium 7 or 8
Pentium Pro
*

BTS mem,imm8
00001111 10101011 disp
BTS DATA1,2
BTS LIST,2
BTS DATA2[DI],3
BTS [EAX],1
BTS FROG,6
Dodatak A
8086 -
8088 -
80286 -
80386 8
80486 8
Pentium 7 or 8
Pentium Pro
Format Examples Microprocessor Clocks
BTS reg,reg
BTS mem,reg
BTS AX,CX
BTS CX,DX
BTS BP,AX
BTS SI,CX
BTS EAX,EBX
BTS DATA4,AX
BTS LIST,BX
BTS
DATA3[DI],CX
BTS [EBX],DX
BTS [DI],DI
CALL Call procedure (subroutine)
11101000 disp
8086 -
8088 -
80286 -
80386 6
80486 6
Pentium 7 or 13
Pentium Pro
8086 -
8088 -
80286 -
80386 13
80486 13
Pentium 7 or 13
Pentium Pro
Format Examples Microprocessor Clocks
CALL label
(near)
CALL FOR_FUN
CALL HOME
CALL ET
CALL WAITING
CALL SOMEONE
8086 19
8088 23
80286 7
80386 3
80486 3
Pentium 1
Pentium Pro
A-29

10011010 disp
A-30
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Format Examples Microprocessor Clocks
CALL label
(far)
11111111 oo010mmm
CALL FAR PTR DATES
CALL WHAT
CALL WHERE
CALLFARCE
CALL WHOM
8086 28
8088 36
80286 13
80386 17
80486 18
Pentium 4
Pentium Pro
Format Examples Microprocessor Clocks
CALL reg
(near)
CALL mem
(near)
11111111 oo011mmm
CALL AX
CALLBX
CALL CX
CALL DI
CALL SI
CALL ADDRESS
CALL NEAR PTR [DI]
CALL DATA1
CALL FROG
CALL ME_NOW
8086 16
8088 20
80286 7
80386 7
80486 5
Pentium 2
Pentium Pro
8086 21 + ea
8088 29 + ea
80286 11
80386 10
80486 5
Pentium 2
Pentium Pro
Format Examples Microprocessor Clocks
CALL MEM
(far)
CALL FAR_LIST[SI]
CALL
FROM_HERE
CALL TO_THERE
CALL SIXX
CALL OCT
8086 16
8088 20
80286 7
80386 7
80486 5
Pentium 2
Pentium Pro

CBW Convert byte to word (AL -> AX)
10011000
Dodatak A
Example Microprocessor Clocks
CBW
CDQ Convert doubleword to quadword
(EAX ==>EDX:EAX)
1101010000001010
8086 2
8088 2
80286 2
80386 3
80486 3
Pentium 3
Pentium Pro
Example Microprocessor Clocks
CDQ
CLC Clear carry flag
8086 -
8088 -
80286 -
80386 2
80486 2
Pentium 2
Pentium Pro
11111000 O D I T S Z A P C
Example Microprocessor Clocks
CLC
8086 2
8088 2
80286 2
80386 2
80486 2
Pentium 2
Pentium Pro
0
A-31

CLD Clear direction flag
A-32
Zbirka zadataka iz Mikroprocesora i mikrora~unara
11111100 O D I T S Z A P C
Example Microprocessor Clocks
CLC
CLI Clear interupt flag
0
8086 2
8088 2
80286 2
80386 2
80486 2
Pentium 2
Pentium Pro
11111010 O D I T S Z A P C
Example Microprocessor Clocks
CLI
CLTS Clear task switched flag (CR0)
00001111 00000110
0
8086 2
8088 2
80286 3
80386 3
80486 5
Pentium 7
Pentium Pro
Example Microprocessor Clocks
CLTS
8086 -
8088 -
80286 2
80386 5
80486 7
Pentium 10
Pentium Pro

CMC Complement carry flag
Dodatak A
10011000 O D I T S Z A P C
Example Microprocessor Clocks
CMC
CMOVcondition Conditional move
000011110100cccc oorrrmmrn
8086 2
8088 2
80286 2
80386 2
80486 2
Pentium 2
Pentium Pro
Format Examples Microprocessor Clocks
CMOVcc reg,mem
Condition
CMOVNZ
AX,FROG
CMOVC
EAX,[EDI]
CMOVNC
BX,DATA1
CMOVP
EBX,WAITING
CMOVNE DI,[SI]
*
8086 -
8088 -
80286 -
80386 -
80486 -
Pentium -
Pentium
Pro
Codes Mnemonic Flag Description
0000 CMOVO O=1 Move if overflow
0001 CMOVNO O=0 Move If no overflow
0010 CMOVB C = 1 Move if below
0011 CMOVAE C=0 Move if above or equal
0100 CMOVE Z=1 Move if equal/zero
0101 CMOVNE Z=0 Move if not equal/zero
0110 CMOVBE C=1 +
Z=1
Move if below or equal
0111 CMOVA C=O•Z=0 Move if above
1000 CMOVS S=1 Move if sign
A-33

A-34
Zbirka zadataka iz Mikroprocesora i mikrora~unara
1001 CMOVNS S=0 Move if no sign
1010 CMOVP P=1 Move if parity
1011 CMOVNP P=0 Move if no parity
1100 CMOVL S*0 Move if less than
1101 CMOVGE S=0 Move if greater then or
equal
1110 CMOVLE Z=1 +
S=0
Move if less than or equal
1111 CMOVG Z=0+S=0 Move If greater than
CMP Compare
0011l0dw oorrrmmm disp O D I T S Z A P C
* * * * * *
Format Examples Microprocessor Clocks
CMP reg,reg
CMP mem,reg
CMP reg,mem
CMP AX,BX
CMP AL,BL
CMP EAX,EBX
CMP CX,SI
CMP ESI,EDI
CMP DATAY,AL
CMP LIST,SI
CMP DATA6[DI],CL
CMP [EAXI,CL
CMP [EDX+4*ECX],EBX
CMP BL,DATA2
CMP SI,LIST3
CMP CL,DATA2[DI]
CMP CX,[EDI]
CMP ESI,[ECX+200H]
100000sw oo111 mmm disp data
8086 3
8088 3
80286 2
80386 2
80486 1
Pentium 1 or 2
Pentium Pro
8086 9 + ea
8088 13 + ea
80286 7
80386 6
80486 2
Pentium 1 or 2
Pentium Pro
8086 9 + ea
8088 13 + ea
80286 6
80386 6
80486 2
Pentium 1 or2
Pentium Pro

Dodatak A
Format Examples Microprocessor Clocks
CMP reg,imm
CMP mem,imm
0001111w data
CMP CX,3
CMP DI, 1 AH
CMP DL,34H
CMP EDX,1345H
CMP CX,1834H
CMP DATAS,3
CMP BYTE
PTR[EDI],1AH
CMP DADDY,34H
CMP LIST,'A'
CMP
TOAD,1834H
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1 or2
Pentium Pro
8086 10 + ea
8088 14 + ea
80286 6
80386
80486 2
Pentium 1 or2
Pentium Pro
Format Examples Microprocessor Clocks
CMP acc,imm
CMP AX,3
CMP AL,1AH
CMP AH,34H
CMP EAX,1345H
CMP AL,'Y'
CMPS Compare strings
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1
Pentium Pro
1010011w O D I T S Z A P C
* * * * * *
Format Examples Microprocessor Clocks
CMPSB
CMPSW
CMPSD
CMPSB
CMPSW
CMPSD
CMPSB
DATAl,DATA2
REPE CMPSB
REPNE CMPSW
8086 32
8088 30
80286 8
80386 10
80486 8
Pentium 5
A-35

CMPXCHG Compare and exchange
A-36
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Pentium Pro
00001111 1100011 oo rrr mmm O D I T S Z A P C
* * * * * *
Format Examples Microprocessor Clocks
CMPXCHG reg,reg
CMPXCHG EAX,EBX
CMPXCHG ECX,EDX
00001111 1011000w 11rrrrrr
8086 -
8088 -
80286 -
80386 -
80486 6
Pentium 6
Pentium
Pro
Format Examples Microprocessor Clocks
CMPXCHG
mem,reg
CMPXCHG DATAD,EAX
CMPXCHG DATA2,ECX
CMPXCHG Compare and exchange
8086 -
8088 -
80286 -
80386 -
80486 7
Pentium 6
Pentium
Pro
00001111 1011000w 11rrrrrr O D I T S Z A P C
Format Examples Microprocessor Clocks
CMPXCHG8B mem64
CMPXCHG8B DATA3
*
8086 -
8088 -
80286 -
80386 -
80486 -
Pentium 10

CPUID CPU identification code
00001111 10100010
Dodatak A
Pentium
Pro
Example Microprocessor Clocks
CPUID
8086
8088
80286
80386
CWD Convert word to doubleword (AX-->DX:AX)
10011000
80486 -
Pentium 14
Pentium Pro
Example Microprocessor Clocks
CWD
8086 5
8088 5
80286 2
80386 2
80486 3
Pentium 2
Pentium Pro
CWDE Convert word to extended doubleword (AX-->EAX)
10011000
Example Microprocessor Clocks
CWDE
8086 -
8088 -
80286 -
80386 3
80486 3
Pentium 3
A-37

DAA Decimal adjust AL after addition
A-38
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Pentium Pro
00100111 O D I T S Z A P C
? * * * * *
Example Microprocessor Clocks
DAA
DAS Decimal adjust AL after subtraction
8086 4
8088 4
80286 3
80386 4
80486 2
Pentium 3
Pentium Pro
00101111 O D I T S Z A P C
? * * * * *
Example Microprocessor Clocks
DAS
DEC Decrement
8086 4
8088 4
80286 3
80386 4
80486 2
Pentium 3
Pentium Pro
1111111w oo001mmm disp O D I T S Z A P C
? * * * * *
Format Examples Microprocessor Clocks
DEC reg8
DEC BL
DEC BH
DEC CL
DEC DH
DEC AH
8086 3
8088 3
80286 2
80386 2
80486 1
Pentium 1 or3

DEC mem
01001rrr
DEC DATAY
DEC LIST
DEC DATA6[DI]
DEC BYTE PTR [BX]
DEC WORD PTR[EBX]
Pentium Pro
Dodatak A
8086 15 + ea
8088 23 + ea
80286 7
80386 6
80486 3
Pentium 1 or 3
Pentium Pro
Format Examples Microprocessor Clocks
DEC regl6
DEC reg32
DIV Divide
DEC CX
DEC DI
DEC EDX
DEC ECX
DEC BP
8086 3
8088 3
80286 2
80386 2
80486 1
Pentium 1
Pentium Pro
1111011w oo110mmm disp O D I T S Z A P C
? ? ? ? ? ?
Format Examples Microprocessor Clocks
DIV reg
DIV mem
DIV BL
DIV BH
DIV ECX
DIV DH
DIV CX
DIV DATAY
DIV LIST
DIV DATA6[DI]
DIV BYTE PTR [BX]
DIV WORD PTR[EBXI
8086 162
8088 162
80286 22
80386 38
80486 40
Pentium 17-41
Pentium Pro
8086 168
8088 176
80286 25
80386 41
80486 40
Pentium 17--41
A-39

ENTER Create a stack frame
11001000 data
A-40
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Pentium Pro
Format Examples Microprocessor Clocks
ENTER imm,0
ENTER imm,l
ENTER
imm,imm
ENTER 4,0
ENTER 8,0
ENTER 100,0
ENTER 200,0
ENTER 1024,0
ENTER 4,1
ENTER 10,1
ENTER 3,6
ENTER 100,3
ESC Escape (obsolete see coprocessor)
HLT Halt
11110100
8086 -
8088 -
80286 11
80386 10
80486 14
Pentium 11
Pentium Pro
8086 -
8088 -
80286 12
80386 15
80486 17
Pentium 15
Pentium Pro
8086 -
8088 -
80286 12
80386 15
80486 17
Pentium 15 + 2n
Pentium Pro
Example Microprocessor Clocks

HLT
IDIV Integer (signed) division
Dodatak A
8086 2
8088 2
80286 2
80386 5
80486 4
Pentium varies
Pentium Pro
111011w oo111mmm disp O D I T S Z A P C
? ? ? ? ? ?
Format Examples Microprocessor Clocks
IDIV reg
IDIV mem
IDIV BL
IDIV BH
IDIV ECX
IDIV DH
I DIV CX
IDIV DATAY
IDIV LIST
IDIV DATA6[DI]
IDIV BYTE PTR
[BX]
IDIV WORD
PTR [EBX]
IMUL Integer (signed) multiplication
8086 184
8088 184
80286 25
80386 43
80486 43
Pentium 22-46
Pentium Pro
8086 190
8088 194
80286 28
80386 46
80486 44
Pentium 22-46
Pentium Pro
1111011w oo101mmm disp O D I T S Z A P C
* ? ? ? ? *
Format Examples Microprocessor Clocks
IMUL reg
IMUL BL
IMUL CX
IMULECX
IMUL DH
8086 154
8088 154
80286 21
80386 38
IMUL AL 80486 42
A-41

IMUL mem
A-42
Zbirka zadataka iz Mikroprocesora i mikrora~unara
IMUL DATAY
IMUL LIST
IMUL
DATA6[DI]
IMUL WORD
PTR [EBX]
011010s1 oorrmmm disp data
Pentium 10-11
Pentium Pro
8086 160
8088 164
80286 24
80486 42
Pentium 10-11
Pentium Pro
Format Examples Microprocessor Clocks
IMUL reg,imm
IMUL
reg,reg,imm
IMUL
reg,mem,imm
IMUL CX,16
IMUL DI, 100
IMUL EDX,20
IMUL DX,AX,2
IMUL CX,DX,3
IMUL BX,AX,33
IMUL
CX,DATAY,99
00001111 10101111 oorrmmm disp
8086 -
8088 -
80286 21
80386 38
80486 42
Pentium 10
Pentium Pro
8086 -
8088 -
80286 21
80386 38
80486 42
Pentium 10
Pentium Pro
8086 -
8088
80286 24
80386 38
80486 42
Pentium 10
Pentium Pro
Format Examples Microprocessor Clocks
IMUL reg,reg
IMUL CX,DX
IMUL DI,BX
8086 -
8088 -
IMUL EDX,EBX 80286 -

IMUL
reg,mem
IMUL
DX,DATAY
IMUL CX,LIST
IMUL
ECX,DATA6[DI]
IN Input data from port
1110010w port#
Dodatak A
80386 38
80486 42
Pentium 10
Pentium Pro
8086 -
8088
80286 -
80386 41
80486 42
Pentium 10
Pentium Pro
Format Examples Microprocessor Clocks
IN acc,pt
1110110w
IN AL,12H
IN AX,12H
IN AL,0FFH
IN AX,0A0H
IN EAX,10H
8086 10
8088 14
80286 5
80386 12
80486 14
Pentium 7
Pentium Pro
Format Examples Microprocessor Clocks
IN acc,DX
INC Increment
IN AL,DX
IN AX,DX
IN EAX,DX
8086 8
8088 12
80286 5
80386 13
80486 14
Pentium 7
Pentium Pro
1111111w oo000mmm disp O D I T S Z A P C
* * * * *
Format Examples Microprocessor Clocks
A-43

INC reg8
INC mem
A-44
INC BL
INC BH
INC AL
INC AH
INC DH
Zbirka zadataka iz Mikroprocesora i mikrora~unara
INC DATA3
INC LIST
INC COUNT
INC BYTE PTR
[DI]
INC WORD PTR
[ECX]
8086 3
8088 3
80286 2
80386 2
80486 1
Pentium 1 or3
Pentium Pro
8086 15 + ea
8088 23 + ea
80286 7
80386 6
80486 3
Pentium 1 or 3
Pentium Pro
INC regl6 INC CX 8086 3
INC reg32
INC DX
INC BP
INC ECX
INC ESP
INS Input string from port
0110110w
8088 3
80286
80386 2
80486 1
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks
INSB
INSW
INSD
INT Interrupt
11001101 type
INSB
INSW
INSD
INS DATA2
REP INSB
8086 -
8088 -
80286 5
80386 15
80486 17
Pentium 9
Pentium Pro

Dodatak A
Format Examples Microprocessor Clocks
INT type
INT 12H
INT 15H
INT 21 H
INT 2FH
INT 10H
INT 3 Interrupt 3
11001100
8086 51
8088 71
80286 23
80386 37
80486 30
Pentium 16-82
Pentium Pro
Example Microprocessor Clocks
INT 3
INTO Interrupt on overflow
11001110
8086 52
8088 72
80286 23
80386 33
80486 26
Pentium 1
Pentium Pro
Example Microprocessor Clocks
INTO
INVD invalidate data cache
00001111 00001000
8086 53
8088 73
80286 24
80386 35
80486 28
Pentium 13~56
Pentium Pro
A-45

A-46
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Example Microprocessor Clocks
INVD
IRET/IRETD Return from interrupt
8086 -
8088 -
80286 -
80386 -
80486 4
Pentium 15
Pentium Pro
11001101 data O D I T S Z A P C
* * * * * * * * *
Format Examples Microprocessor Clocks
IRET
IRETD
IRET
IRETD
IRET 100
Jcondition Conditional jump
0111cccc disp
8086 32
8088 44
80286 17
80386 22
80486 15
Pentium 8-27
Pentium Pro
Format Examples Microprocessor Clocks
Jcnd label
(8-bit disp)
JA ABOVE
JB BELOW
JG GREATER
JE EQUAL
JZ ZERO
000011111000 cccc disp
8086 16/4
8088 16/4
80286 7/3
80386 7/3
80486 3/1
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks

Jcnd label
(16-bit disp)
JNE
NOT_MORE
JLE
LESS_OR_SO
Dodatak A
8086 -
8088 -
80286 -
80386 7/3
80486 3/1
Pentium 1
Pentium Pro
Codes Mnemonic Flag Description
0000 JO O=1 Jump if overflow
0001 JNO O=0 Jump if no overflow
0010 JB/NAE C=1 Jump if below
0011 JAE/JNB C=0 Jump if above or equal
0100 JE/JZ Z=1 Jump if equal/zero
0101 JNE/JNZ Z=1 Jump if not equal/zero
0110 JBE/JNA C=1+Z=1 Jump if below or equal
0111 JA/JNBE C=O*Z=0 Jump if above
1000 JS S = 1 Jump if sign
1001 JNS S=0 Jump if no sign
1010 JP/JPE P = 1 Jump If parity
1011 JNP/JPO P=0 Jump if no parity
1100 JL/JNGE S*0 Jump if less than
1101 JGE/JNL S=0 Jump if greater than or
equal
1110 JLE/JNG Z = 1 + S - O Jump if less than or equal
1111 JG/JNLE Z=0+S=O Jump if greater than
JCXZ/JECXZ Jump if CX (ECX) equals zero
11100011
Format Examples Microprocessor Clocks
JCXZ label
JECXZ label
JCXZ ABOVE
JCXZ BELOW
JECXZ
GREATER
JECXZ EQUAL
JCXZ NEXT
8086 18/6
8088 18/6
80286 8/4
80386 9/5
80486 8/5
Pentium 6/5
Pentium Pro
A-47

Jmp Jump
11101011 disp
A-48
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Format Examples Microprocessor Clocks
JMP label
(short)
11101001 disp
JMP SHORT UP
JMP SHORT
DOWN
JMP SHORT
OVER
JMP SHORT
CIRCUIT
JMP SHORT
JOKE
8086 15
8088 15
80286 7
80386 7
80486 3
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks
JMP label
(near)
11101011 disp
JMP VERS
JMP FROG
JMP UNDER
JMP NEAR PTR
OVER
8086 15
8088 15
80286 7
80386 7
80486 3
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks
JMP label
(far)
11111111 oo100mmm
JMP
NOT_MORE
JMP UNDER
JMP AGAIN
JMP FAR PTR
THERE
8086 15
8088 15
80286 11
80386 12
80486 17
Pentium 3
Pentium Pro
Format Examples Microprocessor Clocks
JMP reg
(near)
JMP AX
JMP EAX
JMP CX
8086 11
8088 11
80286 7
JMP DX 80386 7

JMP mem
(near)
11111111 oo101mmm
JMP VERS
JMP FROG
JMP CS:UNDER
JMP
DATAI[DI+2]
Dodatak A
80486 3
Pentium 2
Pentium Pro
8086 18 + ea
8088 18 + ea
80286 11
80386 10
80486 5
Pentium 4
Pentium Pro
Format Examples Microprocessor Clocks
JMP mem
(far)
JMP WAY_OFF
JMP TABLE
JMPUP
JMP
OUT_OF_HERE
LAHF Load AH from flags
10011111
8086 24 + ea
8088 24 + ea
1280286 15
80386 12
80486 13
Pentium 4
Pentium Pro
Example Microprocessor Clocks
LAHF
LAR Load access rights byte
8086 4
8088 4
80286 2
80386 2
80486 3
Pentium 2
Pentium Pro
00001111 00000010 oorrrmmm disp O D I T S Z A P C
Format Examples Microprocessor Clocks
*
A-49

LAR reg,reg
LAR reg,mem
A-50
LAR AX,BX
Zbirka zadataka iz Mikroprocesora i mikrora~unara
LAR CX,DX
LAR ECX,EDX
LAR CX,DATA1
LAR AX,LIST3
LAR ECX,TOAD
LEA Load effective address
10001101 oorrrmmm disp
8086 -
8088 -
80286 14
80386 15
80486 11
Pentium 8
Pentium Pro
8086 -
8088 -
80286 16
80386 16
80486 11
Pentium 8
Pentium Pro
Format Examples Microprocessor Clocks
LEA reg,mem
LEA DI,DATA3
LEA SI,LIST2
LEA
BX,ARRAY_PTR
LEA CX,PNTR
LEAVE Leave high-level procedure
11001001
8086 2 + ea
8088 2 + ea
80286 3
80386 2
80486 2
Pentium 1
Pentium Pro
Example Microprocessor Clocks
LEAVE
8086
8088
80286
80386
80486 5
-
-
5
4

Pentium
LES Load far pointer to ES and register
11000100 oorrrmmrn
Pentium Pro
Dodatak A
Format Examples Microprocessor Clocks
LES reg,mem
LES DI,DATA3
LES SI,LIST2
LES
BX,ARRAY_PTR
LES CX,PNTR
LFS Load far pointer to FS and register
00001111 10110100oorrrmmmdisp
8086 16 + ea
8088 24 + ea
80286 7
80386 7
80486 6
Pentium 4
Pentium Pro
Format Examples Microprocessor Clocks
LFS reg,mem
LFS DI,DATA3
LFS SI,LIST2
LFS
BX,ARRAY_PTR
LFS CX,PNTR
LGDT Load global descriptor table
0000111100000001 oo010mmm disp
8086 -
8088 -
80286 -
80386 7
80486 6
Pentium 4
Pentium Pro
Format Examples Microprocessor Clocks
LGDT mem64
LGDT DESCRIP
LGDT TABLED
8086 -
8088 -
80286 11
80386 11
80486 11
Pentium 6
3
A-51

LGS Load far pointer to GS and register
00001111 10110101 oorrrmmm disp
A-52
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Pentium Pro
Format Examples Microprocessor Clocks
LGS reg,mem
LGS DI,DATA3
LGS SI,LIST2
LGS BX,ARRAY
PTR
LGS CX,PNTR
LIDT Load interrupt descriptor table
00001111 00000001 oo011 mmm
disp
8086
8088
80286 -
80386 7
80486 6
Pentium 4
Pentium Pro
Format Examples Microprocessor Clocks
LIDT mem64 LIDT DATA3
LIDT LIST2
LLDT Load local descriptor table
00001111 00000000 oo010mmm disp
8086
8088 -
80286 12
80386 11
80486 11
Pentium 6
Pentium Pro
Format Examples Microprocessor Clocks
LLDT reg LLDT BX
LLDT DX
LLDT CX
8086 -
8088 -
80286 17
80386 20
80486 11
Pentium 9
Pentium Pro

LLDT mem LLDT DATA1
LLDT LIST3
LLDT TOAD
Dodatak A
8086 -
8088 -
80286 19
80386 24
80486 11
Pentium
Pentiurn Pro
LMSW Load machine status word (80286 only)
00001111 00000001 oo110mmm disp
Format Examples Microprocessor Clocks
LMSW reg LMSW BX
LMSW DX
LMSW CX
LMSW mem LMSW DATA1
LOCK Lock the bus
11110000
LMSW LIST3
LMSW TOAD
8086 -
8088 -
80286 3
80386 10
80486 2
Pentium 8
Pentium Pro
8086 -
8088 -
80286 6
80386 13
80486 3
Pentium 8
Pentium Pro
Format Examples Microprocessor Clocks
LOCK:inst LOCK:XCHG AX,BX
LOCK:ADD AL,3
8086 2
8088 3
80286 0
80386 0
80486 1
A-53

LODS Load string operand
10101low
A-54
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks
LODSB
LODSW
LODSD
LODSB
LODSW
LODSD
LODS DATA3
8086 12
8088 15
80286 5
80386 5
80486 5
Pentium 2
Pentium Pro
LOOP/LOOPD Loop until CX=0 or ECX=0
11100010 disp
Format Examples Microprocessor Clocks
LOOP label
LOOPD label
LOOP NEXT
LOOP BACK
LOOPD LOOPS
LOOPE/LOOPED Loop while equal
11100001 disp
8086 17/5
8088 17/5
80286 8/4
80386 11
80486 7/6
Pentium 5/6
Pentium Pro
Format Examples Microprocessor Clocks
LOOPE label
LOOPED label
LOOPZ label
LOOPZD label
LOOPE AGAIN
LOOPED UNTIL
LOOPZ ZORRO
LOOPZD WOW
8086 18/6
8088 18/6
80286 8/4
80386 11
80486 9/6

Dodatak A
Pentium 7/8
Pentium Pro
LOOPNE/LOOPNED Loop while not equal
11100000 disp
Format Examples Microprocessor Clocks
LOOPNE label
LOOPNED
label
LOOPNZ label
LOOPNZD
label
LOOPNE FORWARD
LOOPNED UPS
LOOPNZ TRY_AGAIN
LOOPNZO WOO
LSL Load segment limit
8086 19/5
8088 19/5
80286 8/4
80386 11
80486 9/6
Pentium 7/8
Pentium Pro
00001111 00000011 oorrrmmm disp O D I T S Z A P C
Format Examples Microprocessor Clocks
LSL reg,reg
LSL AX,BX
LSL CX,BX
LSL EDX,EAX
LSL reg,mem LSL AX,LIMIT
LSL EAX,NUM
8086 -
8088 -
80286 14
80386 25
80486 10
Pentium 8
Pentium Pro
8086
8088
LSS Load far pointer to SS and register
80286 16
80386 26
80486 10
Pentium 8
Pentium Pro
*
A-55

00001111 10110010 oorrrmmm disp
A-56
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Format Examples Microprocessor Clocks
LSS reg,mem LSS DI,DATA1
LSS
SP,STACK_TOP
LSS CX,ARRAY
LTR Load task register
00001111 00000000 oo001mmm disp
8086
8088
80286
80386 7
80486 6
Pentium 4
Pentium Pro
Format Examples Microprocessor Clocks
LTR reg LTR AX
LTR CX
LTR DX
LTR mem16 LTR TASK
MOVE Move data
LTR NUM
100010dw oorrrmmm disp
8086 -
8088 -
80286 17
80386 23
80486 20
Pentium 10
Pentium Pro
8086 -
8088 -
80286 19
80386 27
80486 0
Pentium 10
Pentium Pro
Format Examples Microprocessor Clocks
MOV reg.reg MOV CL,CH
8086 2
MOV BH,CL 8088 2

MOV CX,DX
MOV EAX,EBP
MOV ESP,ESI
MOV mem,reg MOV DATA7,DL
MOV NUMB,CX
MOV TEMP,EBX
MOV FECXI,BL
MOV [DI],DH
MOV reg,mem MOV DL,DATA8
MOV DX,NUMB
MOV
EBX,TEMP+3
MOV
CH,TEMP[EDI]
MOV CL,DATA2
1100011woo000mmm disp data
Dodatak A
80286 2
80386 2
80486 1
Pentium 1
Pentium Pro
8086 9 + ea
8088 13 + ea
80286 3
80386 2
80486 1
Pentium 1
Pentium Pro
8086 10 + ea
8088 12 + ea
80286 5
80386 4
80486 1
Pentium 1
Penlium Pro
Format Examples Microprocessor Clocks
MOV
mem,imm
1011wrrr data
MOV
DATAF,23H
MOV LIST,12H
MOV BYTE PTR
[DI],2
MOV
NUMB,234H
MOV DWORD
PTR[ECX],1
8086 10 + ca
8088 14 + ea
80286 3
80386 2
80486 1
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks
MOV reg,imm MOV BX,22H
MOV CX, 12H
MOV CL,2
MOV ECX,123456H
MOV DI,100
8086 4
8088 4
80288 3
80386 2
80486 1
Pentium 1
A-57

101000dw disp
A-58
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Pentium Pro
Format Examples Microprocessor Clocks
MOV mem,acc MOV DATAF,AL
MOV LIST,AX
MOV
NUMB,EAX
MOV acc,mem MOV AL,DATAE
10001ld0 oosssmmm disp
MOV AX,LIST
MOV EAX,LUTE
MOV seg,reg MOV SS,AX
MOV DS,DX
MOV ES,CX
MOV FS,BX
MOV GS,AX
MOV seg,mem MOV SS,STACK-
TOP
MOV DS,DATAS
MOV ES,TEMP1
MOV reg,seg MOV BX,DS
MOV CX,FS
MOV CX,ES
8086 10
8088 14
80286 3
80386 2
80486 1
Pentium 1
Pentiurn Pro
8086 10
8088 14
80286
80386 4
80486 1
Pentium 1
Pentium Pro
8086 2
8088 2
80286 2
80386 2
80486 1
Pentium 1
Pentium Pro
8086 8 + ea
8088 12 + ea
80286 2
80386 2
80486 1
Pentium 2 or 3
Pentium Pro
8086 2
8088 2
80286 2
80386 2

MOV mem,seg MOV DATA2,CS
MOV TEMP,DS
MOV NUMB1,SS
MOV TEMP2,GS
00001111 001000d0 11rrrmmm
Dodatak A
80486 1
Pentium 1
Pentium Pro
8086 9 + ea
8088 13 + ea
80286 3
80386 2
80486 1
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks
MOV reg,cr MOV EBX,CRO
MOV ECX,CR2
MOV EBX,CR3
MOV cr.reg MOV CRO,EAX
MOV CR1,EBX
MOV CR3,EDX
00001111 001000d1 11rrrmmm
8086 -
8088 -
80286 -
80386 6
80486 4
Pentium 4
Pentium Pro
8086 -
8088 -
80286 -
80366 10
80486 4
Pentium 12--46
Pentium Pro
Format Examples Microprocessor Clocks
MOV reg,dr MOV EBX,DR6
MOV ECX,DR7
MOV EBX,DR1
8086 -
8088 -
80286 -
80386 22
80486 10
Pentium 11
Pentium Pro
MOV dr,reg MOV DR0,EAX 8086 -
A-59

A-60
Zbirka zadataka iz Mikroprocesora i mikrora~unara
MOV DR1,EBX
MOV DR3,EDX
00001111 001001do 11rrrmmm
8088 -
80286 -
80386 22
80486 11
Pentium 11
Pentium Pro
Format Examples Microprocessor Clocks
MOV reg,tr MOV EBX,TR6
MOV ECX,TR7
MOV tr, reg MOV TR6,EAX
MOV TR7,EBX
MOVS Move string data
1010010w
8086 -
8088 -
80286 -
80386 12
80486 4
Pentium 11
Pentium Pro
8086 -
8088 -
80286 -
80386 12
80486 6
Pentium 11
Pentium Pro
Format Examples Microprocessor Clocks
MOVSB
MOVSW
MOVSD
MOVSB
MOVSW
MOVSD
MOVS
DATAl,DATA2
MOVSX Move with sign extend
8086 18
8088 26
80286 5
80386 7
80486 7
Pentium 4
Pentium Pro

00001111 1011111w oorrrmmm disp
Dodatak A
Format Examples Microprocessor Clocks
MOVSX
reg,reg
MOVSX BX,AL
MOVSX EAX,DX
MOVSX reg,mem MOVSX
AX,DATA34
MOVSX EAX,NUMB
MOVZX Move with zero extend
00001111 1011011w oorrrmmm disp
8086 -
8088 -
80286 -
80386 3
80486 3
Pentium 3
Pentium Pro
8086 -
8088 -
80286 -
80386 6
80486 3
Pentium 3
Pentium Pro
Format Examples Microprocessor Clocks
MOVZX
reg,reg
MOVZX BX,AL
MOVZX EAX,DX
MOVZX reg,mem MOVZX AX,DATA34
MOVZX EAX,NUMB
8086 -
8088 -
80286 -
80386 3
80486 3
Pentium 3
Pentium Pro
8086 -
8088 -
80286 -
80386 6
80486 3
Pentium 3
Pentium Pro
A-61

MUL Multiply
A-62
Zbirka zadataka iz Mikroprocesora i mikrora~unara
111101lw 00100MMM disp O D I T S Z A P C
* ? ? ? ? *
Format Examples Microprocessor Clocks
MUL reg MUL BL
MUL CX
MUL EDX
MUL mem MUL DATA9
NEG Negate
MUL WORD PTR
[ESI]
8086 118
8088 143
80286 21
80388 38
80486 42
Pentium 10 or 11
Pentium Pro
8086 139
8088 143
80286 24
80386 41
80486 42
Pentium 11
Pentium Pro
111101lw oool1mmm disp O D I T S Z A P C
* * * * * *
Format Examples Microprocessor Clocks
NEG reg NEG BL
NEG mem
NEG CX
NEG EDI
NEG DATA9
NEG WORD PTR
[ESI]
8086 3
8088 3
80286 2
80386 2
80486 1
Pentium 1 or3
Pentium Pro
8086 16 + ea
8088 24 + ea
80286 7
80386 6
80486 3

NOP No operation
10010000
Dodatak A
Pentium 1 or3
Pentium Pro
Example Microprocessor Clocks
NOP
NOT One's complement
111101lw oo010mmm disp
8086 3
8088 3
80286 3
80386 3
80486 3
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks
NOT reg
NOT mem
OR Inclusive-OR
NOT BL
NOT CX
NOT EDI
NOT DATA9
NOT WORD PTR [ESI]
8086 3
8088 3
80286 2
80386 2
80486 1
Pentium 1 or3
Pentium Pro
8086 16 + ea
8088 24 + ea
80286 7
80386 6
80486 3
Pentium 1 or3
Pentium Pro
A-63

A-64
Zbirka zadataka iz Mikroprocesora i mikrora~unara
000010dw oorrrmmm disp O D I T S Z A P C
0 * * ? * 0
Format Examples Microprocessor Clocks
OR reg,reg
OR mem,reg
OR reg,mem
OR AX,BX
OR AL,BL
OR EAX,EBX
OR CX,SI
OR ESI,EDI
OR DATAY,AL
OR LIST,ST
OR DATA2[D1],CL
OR [EAX],BL
OR
[EBX+2*ECX],EDX
OR BL,DATA1
OR SI,LIST1
OR CL,DATA2[SI]
OR CX,[ESI]
OR ESI,[2*ECX]
100000sw o000lmmm disp data
8086 3
8088 3
80286 2
80386 2
80486 1
Pentium 1 or 2
Pentium Pro
8086 16 + ea
8088 24 + ea
80286 7
80386 7
80486 3
Pentium 1 or3
Pentium Pro
8086 9 + ea
8088 13 + ea
80286 7
80386 6
80486 2
Pentium 1 or3
Pentium Pro
Format Examples Microprocessor Clocks
OR reg,imm
OR CX,3
OR D1,1AH
OR DL,34H
OR EDX,1345H
OR CX, 1834H
OR mem,imm OR DATAS,3
OR BYTE
PTR[EDI],1AH
OR DADDY,34H
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1or 3
Pentium Pro
8086 17 + ea
8088 25 + ea
80286 7

0000110w data
OR LIST,'A'
OR TOAD,1834H
Dodatak A
80386 7
80486 3
Pentium 1 or3
Pentium Pro
Format Examples Microprocessor Clocks
OR acc,imm OR AX,3
OR AL. 1AH
OR AH,34H
OR EAX, 1345H
OR AL,'Y'
OUT Output data to port
111001lw port#
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks
OUT pt,acc OUT 12H,AL
1110111w
OUT 12H,AX
OUT 0FFH,AL
OUT 0A0H,AX
OUT 10H,EAX
8086 10
8088 14
80286 3
80386 10
80486 10
Pentium 12--26
Pentium Pro
Format Examples Microprocessor Clocks
OUT DX,acc OUT DX,AL
OUT DX,AX
OUT DX,EAX
OUTS Output string to port
8086 8
8088 12
80286 3
80386 1 1
80486 10
Pentium 12--26
Pentium Pro
A-65

0110111w
A-66
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Format Examples Microprocessor Clocks
OUTSB
OUTSW
OUTSD
OUTSB
OUTSW
OUTSD
OUTS DATA2
REP OUTSB
POP pop data from stack
01011rrr
8086 -
8088 -
80286 5
80386 14
80486 10
Pentium 13--27
Pentium Pro
Format Examples Microprocessor Clocks
POP reg POP CX
POP AX
POP EDI
10001111 oo000mmm disp
8086 8
8088 12
80286 5
80386 4
80486 1
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks
POP mem POP DATA1
00sss111
POP LISTS
POP NUMBS
8086 17 + ea
8088 25 + ea
80286 5
80386 5
80486 4
Pentium 3
Pentium Pro
Format Examples Microprocessor Clocks
POP seg POP FS
POP GS
8086 -
8088 -
80286 -

Dodatak A
80386 7
80486 3
Pentium 3
Pentium Pro
POPA/POPAD Pop all registers from stack
01100001
Example Microprocessor Clocks
POPA
POPAD
POPF/POPFD Pop flags from stack
8086 -
8088 -
80286 19
80386 24
80486 9
Pentium 5
Pentium Pro
10010000 O D I T S Z A P C
* * * * * * * * *
Example Microprocessor Clocks
POPF
POPFD
PUSH Push data onto stack
01010rrr
8086 8
8088 12
80286 5
80386 5
80486 6
Pentium 4 or 6
Pentium Pro
Format Examples Microprocessor Clocks
PUSH reg PUSH CX
PUSH AX
8086 11
8088 15
PUSH EDI 80286 3
A-67

11111111 oo111mmm disp
A-68
Zbirka zadataka iz Mikroprocesora i mikrora~unara
80386 2
80486 1
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks
PUSH mem PUSH DATA1
00ss110
PUSH LISTS
PUSH NUMBS
8086 16 + ea
8088 24 + ea
80286 5
80386 5
80486 4
Pentium 1 or 2
Pentium Pro
Format Examples Microprocessor Clocks
PUSH seg PUSH ES
00001111 l0sss000
PUSH CS
PUSH DS
8086 10
8088 14
80286 3
80386 2
80486 3
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks
PUSH seg PUSH fS
011010s0 data
PUSH GS
8086 -
8088 -
80286 -
80386 2
80486 3
Pentium 1
Pentium Pro
Format Examples Microprocessor Clocks
PUSH imm
PUSH 2000H
PUSH 53220
PUSHW 1 OH
PUSH’,’
8086 -
8088 -
80286 3

PUSHD 100000H
Dodatak A
80386 2
80486 1
Pentium 1
Pentium Pro
PUSHA/PUSHAD Push all registers onto stack
01110000
Example Microprocessor Clocks
PUSHA
PUSHAD
PUSHF/PUSHFD Push flags onto stack
10011100
8086 -
8088 -
80286 17
80386 18
80486 11
Pentium 5
Pentium Pro
Example Microprocessor Clocks
PUSHF
PUSHFD
RLC/RCR/ROL/ROR Rotate
8086 10
8088 14
80286 3
80386 4
80486 3
Pentium 3 or 4
Pentiurn Pro
1101000w 00mmmm disp O D I T S Z A P C
* *
TTT=000=ROL, TTT=00l=ROR, TTT=010=RCL, and TTT=011=RCR
Format Examples Microprocessor Clocks
A-69

ROL reg, 1
ROR reg, 1
RCL reg, 1
RCR reg,1
ROL mem,1
ROR mem, 1
RCL mem,1
RCR mem,1
A-70
Zbirka zadataka iz Mikroprocesora i mikrora~unara
ROL CL, 1
ROL DX,1
ROR CH,1
ROR SI,1
RCL CL,1
RCL SI,l
RCR AH,1
RCR EBX,1
ROL DATAY,1
ROL LIST, 1
ROR DATA2[DI],1
ROR BYTE PTR
[EAX],1
RCL DATA1,1
RCL LIST,1
RCR
DATA2[SI],l
RCR WORD PTR
[ESI],1
110100lw ooTTTmmm disp
8086 2
8088 2
80286 2
80386 3
80486 3
Pentium 1 or 3
Pentium Pro
8086 2
8088 2
80286 2
80386 9
80486 3
Pentium 1 or 3
Pentium Pro
8086 5 + ea
8088 23 + ea
80286 7
80386 7
80486 4
Pentium 1 or 3
Pentium Pro
8086 15 + ea
8088 23 + ea
80286 7
80386 10
80486 4
Pentium 1 or 3
Pentium Pro
Format Examples Microprocessor Clocks
ROL reg,CL
ROR reg,CL
ROL CH,CL
ROL DX,CL
ROR AL,CL
ROR ESI,CL
8086 8 + 4n
8088 8 + 4n
80286 5 + n
80386 3
80486 3
Pentium 4

RCL reg,CL
RCR reg,CL
ROL mem,CL
ROR mem,CL
RCL mem,CL
RCR mem,CL
RCL CH,CL
RCL SI,CL
RCR AH,CL
RCR EBX,CL
ROL
DATAY,CL
ROL LIST,CL
ROR
DATA2[D1],CL
ROR BYTE PTR
[EAX],CL
RCL
DATAL,CL
RCL LIST,CL
RCR
DATA2[SI],CL
RCR WORD
PTR [ESI],CL
1100000w ooTTTmmm disp data
Pentium Pro
Dodatak A
8086 8 + 4n
8088 8 + 4n
80286 5+n
80386 9
80486 3
Pentium 7-27
Pentium Pro
8086 20 + 4n
8088 28 + 4n
80286 8+n
80386 7
80486 4
Pentium 4
Pentium Pro
8086 20 + 4n
8088 28 + 4n
80286 8+n
80386 10
80486 9
Pentium 9-26
Pentium Pro
Format Examples Microprocessor Clocks
ROL reg,imm
ROR reg,imm
RCL reg,imm
RCR reg,imm
ROL CH,4
ROL DX,5
ROR AL,2
ROR ESI, 14
RCL CL,2
RCL SI,l 2
RCR AH,5
RCR EBX,18
8086 -
8088 -
80286 5 + n
80386 3
80486 2
Pentium. 1 or 3
Pentium Pro
8086 -
8088 -
80286 5 + n
80386 9
80486 8
A-71

ROL mem,imm
ROR mem,imm
RCL mem,imm
RCR mem,imm
A-72
Zbirka zadataka iz Mikroprocesora i mikrora~unara
ROL DATAY,4
ROL LIST,3
ROR
DATA2[DI],7
ROR BYTE PTR
[EAX], 11
RCL DATA1,5
RCL LIST,3
RCR
DATA2[SI],9
RCR WORD
PTR [ESI],8
RDMSR Read model specific register
00001111 00110010
Pentium 8-27
Pentium Pro
8086 -
8088 -
80286 8 + n
80386 7
80486 4
Pentium 1 or3
Pentium Pro
8086 -
8088 -
80286 8+n
80386 10
80486 9
Pentium 8-27
Pentium Pro
Example Microprocessor Clocks
RDMSR
REP Repeat prefix
11110011 1010010w
8086 -
8088 -
80286 -
80386 -
80486 -
Pentium 20-24
Pentium Pro
Format Examples Microprocessor Clocks
REP MOVS REP MOVSB
REP MOVSW
REP MOVSD
REP MOVS
8086 9 + 17n
8088 9 + 25n
80286 5 + 4n

11110011 1010101w
DATAl,DATA2
Dodatak A
80386 8+ 4n
80486 12 + 3n
Pentium 13 + n
Pentium Pro
Format Examples Microprocessor Clocks
REP STOS REP STOSB
11110011 0110110w
REP STOSW
REP STOSD
REP STOS
ARRAY
8086 9 + l0n
8088 9 + 14n
80286 4 + 3n
80386 5+ 5n
80486 7+ 4n
Pentium 9 + n
Pentium Pro
Format Examples Microprocessor Clocks
REP INS REP INSB
11110011 0110111w
REP INSW
REP INSD
REP INS
ARRAY
8086 -
8088 -
80286 5 + 4n
80386 12 + 5n
80486 17 + 5n
Pentium 25+3n
Pentum Pro
Format Examples Microprocessor Clocks
REP OUTS
REP OUTSB
REP OUTSW
REP OUTSD
REP OUTS ARRAY
REPE/REPNE Repeat conditional
11110011 1010011w
8086 -
8088 -
80286 5 + 4n
80386 12 + 5n
80486 17 + 5n
Pentium 25 + 4n
Pentium Pro
Format Examples Microprocessor Clocks
A-73

REPE CMPS
11110011 1010111w
A-74
Zbirka zadataka iz Mikroprocesora i mikrora~unara
REPE CMPSB
REPE CMPSW
REPE CMPSD
REPE CMPS
DATAl,DATA2
8086 9 + 22n
8088 9 + 30n
80286 5 + 9n
80386 5 + 9n
80486 7 +7n
Pentium 9 + 4n
Pentium Pro
Format Examples Microprocessor Clocks
REPE SCAS
11110010 1010011w
REPE SCASB
REPE SCASW
REPE SCASD
REPE SCAS
ARRAY
8086 9 + 15n
8088 9 + 19n
80286 5 + 8n
80386 5+ 8n
80486 7+ 5n
Pentium 9 + 4n
Pentium Pro
Format Examples Microprocessor Clocks
REPNE CMPS REPNE CMPSB
11110010 101011w
REPNE CMPSW
REPNE CMPSD
REPNE CMPS
ARRAY,LIST
8086 9 + 22n
8088 9 + 30n
80286 5 + 9n
80386 5+ 9n
80486 7+ 7n
Pentium 8 + 4n
Pentium Pro
Format Examples Microprocessor Clocks
REPNE SCAS REPNE SCASB
REPNE SCASW
REPNE SCASD
REPNE SCAS
ARRAY
RET Return from procedure
8086 9 + 15n
8088 9 + 19n
80286 5 + 8n
80386 5 +8n
80486 7+ 5n
Pentium 9 + 4n
Pentium Pro

11000011
Dodatak A
Example Microprocessor Clocks
RET (near)
11000010 data
8086 16
8088 20
80286 11
80386 10
80486 5
Pentium 2
Pentium Pro
Format Examples Microprocessor Clocks
RET imm
(near)
11001011
RET 4
RET 100H
8086 20
8088 24
80286 11
80386 10
80486 5
Pentium 3
Pentium Pro
Format Examples Microprocessor Clocks
RET
(far)
11001010 data
8086 26
8088 34
80286 15
80386 18
80486 13
Pentium 4-23
Pentium Pro
Format Examples Microprocessor Clocks
RET imm
(far)
RET 4
RET 100H
8086 25
8088 33
80286 11
80386 10
80486 5
Pentium 4-23
A-75

A-76
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Pentium Pro
RSM Resume from system management mode
00001111 10101010 O D I T S Z A P C
* * * * * * * * *
Example Microprocessor Clocks
RSM
SAHF Store AH into flags
8086 -
8088 -
80286 -
80386 -
80486 -
Pentium 83
Pentium Pro
10011110 O D I T S Z A P C
Example Microprocessor Clocks
SAHF
SAL/SAR/SHL/SHR Shift
8086 4
8088 4
80286 2
80386 3
80486
Pentium 2
Pentium Pro
* * * * *
1101000w ooTTTmmm disp O D I T S Z A P C
* * * ? * *
TTT = 100 SHL/SAL, TTT = 101=SHR, and TTT= 111= SAR
Format Examples Microprocessor Clocks
SAL reg,1
SHL reg,1
SHR reg,1
SAR reg, 1
SAL CL, 1
SHL DX,1
SAR CH, 1
SHR SI,l
8086 2
8088 2
80286 2
80386 3
80486 3

SAL mem, 1
SHL mem,1
SHR mem,1
BAR mem,1
1101001w oommm disp
SAL DATA1,1
SHL BYTE PTR[DI],l
SAR NUMB, 1
SHR WORD
PTR[EDI],1
Dodatak A
Pentium 1or 3
Pentium Pro
8086 15 + ea
8088 23 + ca
80286 7
80386 7
80486 4
Pentium 1 or3
Pentium Pro
Format Examples Microprocessor Clocks
SAL reg,CL
SHL reg,CL
BAR reg,CL
SHR reg,CL
SAL mem,CL
SHL mem,CL
SAR mem,CL
SHR mem,CL
1101001w oommm disp
SAL CH,CL
8086
SHL DX,CL
BAR AL,CL
SHR ESI,CL
SAL
DATAU,CL
SHL BYTE PTR[ESI],CL
SAR NUMB,CL
SHR TEMP,CL
8086 8 + 4n
8088 8 + 4n
80286 5+n
80386 3
80486 3
Pentium 4
Pentium Pro
8086 20 + 4n
8088 28 + 4n
80286 8+n
80386 7
80486 4
Pentium 4
Pentium Pro
Format Examples Microprocessor Clocks
SAL reg,CL
SHL reg,CL
BAR reg,CL
SHR reg,CL
SAL CH,CL
SHL DX,CL
BAR AL,CL
SHR ESI,CL
1100000w oommmm disp data
8086 8 + 4n
8088 8 + 4n
80286 5+n
80386 3
80486 3
Pentium 4
Pentium Pro
Format Examples Microprocessor Clocks
A-77

SAL reg,imm
SHL reg,imm
SAR reg,imm
SHR reg,imm
SAL mem,imm
SHL mem,imm
SAR mem.imm
SHR mem,imm
A-78
Zbirka zadataka iz Mikroprocesora i mikrora~unara
SAL CH,4
SHL DX,10
SAR AL,2
SHR ESI,23
SAL DATAU,3
SHL BYTE
PTR[ESI],15
SAR NUMB,3
SHR TEMP,5
SBB Subtract with borrow
8086 -
8088 -
80286 5+n
80386 3
80486 2
Pentium 1 or 3
Pentium Pro
8086 -
8088 -
80286 8+n
80386 7
80486 4
Pentium 1 or 3
Pentium Pro
000110dw oorrrmmm disp O D I T S Z A P C
* * * * * *
Format Examples Microprocessor Clocks
SBB reg,reg SBB CL,DL
SBB AX,DX
SBB CH,CL
SBB EAX,EBX
SBB ESI,EDI
SBB mem,reg SBB DATAJ,CL
SBB BYTES,CX
SBB
NUMBS,ECX
SBB [EAX],CX
SBB reg,mem SBB CL,DATAL
SBB CX,BYTES
SBB ECX,NUMBS
SBB DX,[EBX+EDI]
8086 3
8088 3
80286 2
80386 2
80486 1
Pentium 1 or2
Pentium Pro
8086 16 + ea
8088 24 + ea
80286 7
80386 6
80486 3
Pentium 1 or3
Pentium Pro
8086 9 + ea
8088 13 + ea
80286 7

100000sw oool1mmm disp data
Dodatak A
80386 7
80486 2
Pentium 1 or2
Pentium Pro
Format Examples Microprocessor Clocks
SBB reg,imm. SBB CX,3
SBB DI,1AH
SBB DL,34H
SBB EDX,
1345H
SBB CX,1834H
100000sw oool1mmm disp data
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1or 3
Pentium Pro
Format Examples Microprocessor Clocks
SBB reg,imm. SBB CX,3
SBB DI,1AH
SBB DL,34H
SBB EDX,
1345H
SBB CX,1834H
SBB mem,imm SBB DATAS,3
0001110w data
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1or 3
Pentium Pro
8086 17 + ea
SBB BYTE 8088 25 + ea
PTR[EDI],1AH
80286 7
SBB
OADDY,34H
80386 7
SBB LIST,'A' 80486 3
SBB TOAD, Pentium 1 or3
1834H Pentium Pro
Format Examples Microprocessor Clocks
SBB acc,imm SBB AX,3
SBB AL. 1 AH
SBB AH,34H
SBB EAX, 1
345H
8086 4
8088 4
80286 3
80386 2
80486 1
A-79

SCAS Scan string
A-80
Zbirka zadataka iz Mikroprocesora i mikrora~unara
SBB AL,'Y'
Pentium 1
Pentium Pro
1010111w O D I T S Z A P C
* * * * * *
Format Examples Microprocessor Clocks
SCASB
SCASW
SCASD
SCASB
SCASW
SCASD
SCAS DATAF
REP SCASB
SETcondition Conditional set
00001111 1001cccc oo000mrnm
8086 15
8088 19
80286 7
80386 7
80486 6
Pentium 4
Pentium Pro
Format Examples Microprocessor Clocks
SETcnd reg8
SETcnd mem8
Condition
SETA BL
SETB CH
SETG DL
SETE BH
SETZ AL
SETE DATAK
SETAE LESS_OR_SO
8086 -
8088 -
80286 -
80386 4
80486 3
Pentium 1 or 2
Pentium Pro
8086 -
8088 -
80286 -
80386 5
80486 3
Pentium 1 or 2
Pentium Pro
Codes Mnemonic Flag Description

Dodatak A
0000 SETO O = 1 set if overflow
0001 SETNO O=0 Set if no overflow
0010 SETB/SETAE C=1 Set if below
0011 SETAE/SETNB C=0 Set if above or equal
0100 SETE/SETZ Z=1 Set if equal/zero
0101 SETNE/SETNZ Z=0 Set if not equal/zero
0110 SETBE/SETNA C =1 + Z= 1 Set if below or equal
0111 SETA/SETNBE C=0•Z=0 Set if above
1000 SETS S=1 Set if sign
1001 SETNS S=0 Set if no sign
1010 SETP/SETPE P=1 Set if parity
1011 SETNP/SETPO P=0 Set if no parity
1100 SETL/SETNGE S•O Set if less than
1101 SETGE/SETNL S=0 Set K greater than or equal
1110 SETLE/SETNG Z = 1 + S •
O
Set it less than or equal
1111 SETG/SETNLE Z=0+S=O Set if greater than
SGDT/SIDT/SLDT Store descriptor table registers
00001111 00000001 oo000mmm disp
Format Examples Microprocessor Clocks
SGDT mem
SGDT
MEMORY
SGDT GLOBAL
00001111 00000001 00001mmm disp
8086 -
8088 -
80286 11
80386 9
80486 10
Pentium 4
Pentium Pro
Format Examples Microprocessor Clocks
SIDT mem SIDT DATAS
SIDT
INTERRUPT
8086 -
8088 -
80286 12
80386 9
80486 10
A-81

00001111 00000000 oo0000mmm disp
A-82
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Pentium 4
Pentium Pro
Format Examples Microprocessor Clocks
SLDT reg SLDT CX
SLDT OX
SLDT mem SLDT NUMBS
SLDT LOCALS
SHLD/SHRD Double precision shift
00001111 10100100 oorrrmmm disp
data
8086 -
8088 -
80286 2
80386 2
80486 2
Pentium 2
Pentium Pro
8086 -
8088 -
80286 3
80386 2
80486 3
Pentium 2
Pentium Pro
O D I T S Z A P C
? * * ? * *
Format Examples Microprocessor Clocks
SHLD
reg,reg,imm
SHLD mem,reg,imm
SHLD AX,CX,
10
SHLO DX,BX,8
SHLD CX,DX,2
SHLD
DATAQ,CX,8
8086 -
8088 -
80286 -
80386 3
80486 2
Pentium 4
Pentium Pro
8086 -
8088 -
80286 -
80386 7
80486 3
Pentium 4

00001111 10101100 oorrrmmrn disp data
Pentium Pro
Dodatak A
Format Examples Microprocessor Clocks
SHRD reg,reg,imm
SHRD mem,reg,imm
SHRD CX,DX,2
SHRD
DATAZ,DX,4
000011111 0100101 oorrrrnrnm disp
8086 -
8088 -
80286 -
80386 3
80486 2
Pentium 4
Pentium Pro
8086 -
8088 -
80286 -
80386 7
80486 2
Pentium 4
Pentium Pro
Format Examples Microprocessor Clocks
SHLD
reg,reg,CL
SHLD
mem.reg,CL
SHLD
BX,DX,CL
SHLD
DATAZ,DX,CL
000011111 0101101 oorrrmmm disp
8086 -
8088 -
80286 -
80386 3
80486 3
Pentium 4 or 5
Pentium Pro
8086 -
8088 -
80286 -
80386 7
80486 3
Pentium 4 or 5
Pentium Pro
Format Examples Microprocessor Clocks
SHRD SHRD 8086 -
A-83

eg,reg,CL AX,DX,CL
SHRD
mem,reg,CL
A-84
Zbirka zadataka iz Mikroprocesora i mikrora~unara
SHRD
DATAZ,DX,CL
8088 -
80286 -
80386 3
80486 3
Pentium 4 or 5
Pentium Pro
8086 -
8088 -
80286 -
80386 7
80486 3
Pentium 4 or 5
Pentium Pro
SMSW Store machine status word (80286)
00001111 00000001 oo100mmm disp
Format Examples Microprocessor Clocks
SMSW reg SMSW AX
SMSW DX
SMSW BP
SMSW mem SMSW DATAQ
STC Set carry flag
8086 -
8088 -
80286 2
80386 10
80486 2
Pentium 4
Pentium Pro
8086 -
8088 -
80286 3
80386 3
80486 3
Pentium 4
Pentium Pro
11111001 O D I T S Z A P C

Dodatak A
Format Example Microprocessor Clocks
STC STC
STD Set direction flag
8086 2
8088 2
80286 2
80386 2
80486 2
Pentium 2
Pentium Pro
11111101 O D I T S Z A P C
Format Example Microprocessor Clocks
STD STD
STI Set interrupt flag
1
8086 2
8088 2
80286 2
80386 2
80486 2
Pentium 2
Pentium Pro
11111011 O D I T S Z A P C
Format Example Microprocessor Clocks
STI STI
STOS Store string data
1010101w
1
8086 2
8088 2
80286 2
80386 3
80486 5
Pentium 7
Pentium Pro
*
A-85

A-86
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Format Example Microprocessor Clocks
STOSB
STOSW
STOSD
STOSB
STOSW
STOSD
STOS DATA_LIST
REP STOSB
STR Store task register
00001111 00000000 oo001mmm disp
8086 11
8088 15
80286 3
80386 40
80486 5
Pentium 3
Pentium Pro
Format Example Microprocessor Clocks
STR reg STR AX
STR DX
STR BP
STR mem STR DATA3
SUB Subtract
8086 -
8088 -
80286 2
80386 2
80486 2
Pentium 2
Pentium Pro
8086 -
8088 -
80286 2
80386 2
80486 2
Pentium 2
Pendum Pro
00010ldw oorrrmmm disp O D I T S Z A P C
* * * * * *
Format Example Microprocessor Clocks
SUB reg,reg SUB CL,DL
SUB AX,DX
SUB CH,CL 80286 2
8086 3
8088 3

SUB EAX,EBX
SUB ESI,EDI
SUB mem,reg SUB DATAJ,CL
SUB BYTES,CX
SUB
NUMBS,ECX
SUB [EAX],CX
SUB reg,mem SUB
CL,DATAL
SUB CX,BYTES
SUB
ECX,NUMBS
SUB
DX,[EBX+EDI]
100000sw 00101mmm disp data
Dodatak A
80386 2
80486 1
Pentium 1 or 2
Pentium Pro
8086 16 + ea
8088 24 + ea
80286 7
80386 6
80486 3
Pentium 1 or3
Pentium Pro
8086 9 + ea
8088 13 + ea
80286 7
80386 7
80486 2
Pentium 1 or 2
Pentium Pro
Format Example Microprocessor Clocks
SUB reg,imm SUB CX,3
SUB DI,1AH
SUB DL,34H
SUB EDX,1345H
SUB CX,1834H
SUB mem,imm SUB DATAS,3
0010110w data
SUB BYTE
PTR[EDI],1AH
SUB
OADDY,34H
SUB LIST,'A'
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1 or 3
Pentium Pro
8086 17 + ea
8088 25 + ea
80286 7
80386 7
80486 3
SUB
Pentium 1 or 3
TOAD,1834H Pentium Pro
Format Example Microprocessor Clocks
A-87

SUB acc,imm SUB AL,3
A-88
Zbirka zadataka iz Mikroprocesora i mikrora~unara
SUB AX,1AH
SUB EAX,34H
TEST Test operands (logical compare)
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1
Pentium Pro
1000001w oorrrmmm disp O D I T S Z A P C
0 * * ? * 0
Format Example Microprocessor Clocks
TEST reg,reg TEST CL,DL
TEST mem,reg
reg,mem
TEST BX,DX
TEST DH,CL
TEST EBP,EBX
TEST EAX,EDI
TEST
DATAJ,CL
TEST
BYTES,CX
TEST NUMBS,ECX
TEST[EAX],CX
TEST CL,POPS
1111011sw oo000mmm disp data
8086 5
8088 5
80286 2
80386 2
80486 1
Pentium 1 or 2
Pentium Pro
8086 9 + ea
8088 13 + ea
80286 6
80386 5
80486 2
Pentium 1 or2
Pentium Pro
Format Example Microprocessor Clocks
TEST reg,imm TEST BX,3
TEST DI, 1 AH
TEST DH,44H
TEST EDX,1AB345H
TEST SI,1834H
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1 or2
Pentium Pro
TEST mem,imm TEST DATAS,3 8086 11 +ea

1010100w data
TEST BYTE
PTR[EDI],1AH
TEST DADDY,34H
TEST LIST,'A'
TEST TOAD,1834H
Dodatak A
8088 11 +ea
80286 6
80386 5
80486 2
Pentium 1 or2
Pentium Pro
Format Example Microprocessor Clocks
TEST acc,imm TEST AL,3
TEST AX, 1AH
TEST EAX,34H
VERR/VERW Verify read/write
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1
Pentium Pro
00001111 00000000 oo100mmm disp O D I T S Z A P C
Format Example Microprocessor Clocks
VERR reg VERR CX
VERR DX
VERR DI
VERR mem VERR DATAJ
VERR TESTB
00001111 00000000 ool01rnmm disp
8086 -
8088 -
80286 14
80386 10
80486 11
Pentium 7
Pentium Pro
8086 -
8088 -
80286 16
80386 11
80486 11
Pentium 7
Pentium Pro
Format Example Microprocessor Clocks
*
A-89

VERW reg VERW CX
A-90
Zbirka zadataka iz Mikroprocesora i mikrora~unara
VERW DX
VERW DI
VERW mem VERW DATAJ
VERW TESTB
WAIT Wait for coprocessor
10011011
8086 -
8088 -
80286 14
80386 15
80486 11
Pentium 7
Pentium Pro
8086 -
8088 -
80286 16
80386 16
80486 11
Pentium 7
Pentium Pro
Format Example Microprocessor Clocks
WAIT
FWAIT
WAIT
FWAIT
8086 4
8088 4
80286 3
80386 6
80486 6
Pentium 1
Pentium Pro
WBINVD Write-back cache invalidate data cache
00001111 00001001
Format Example Microprocessor Clocks
WBINVD WBINVD
8086 -
8088 -
80286 -
80386 -
80486 5

WRMSR Write to model specific register
00001111 00110000
Dodatak A
Pentium 2000+
Pentium Pro
Format Example Microprocessor Clocks
WRMSR WRMSR
XADD Exchange and add
8086 -
8088 -
80286 -
80386 -
80486 -
Pentium 30-45
Pentium Pro
00001111 1100000w 11rrrrrr O D I T S Z A P C
* * * * * *
Format Example Microprocessor Clocks
XADD reg,reg XADD
EBX,ECX
XADD
EDX,EAX
XADD EDI,EBP
00001111 1100000w oorrrmmm disp
8086 -
8088 -
80286 -
80386 -
80486 3
Pentium 3or4
Pentium Pro
Format Example Microprocessor Clocks
XADD mem.reg
XADD DATA5,ECX
XADD [EBX],EAX
XADD [ECX+4],EBP
8086 -
8088 -
80286 -
80386 -
M80486 4
Pentium 3 or 4
Pentium Pro
A-91

XCHG Exchange
100001lw oorrrmmm
A-92
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Format Example Microprocessor Clocks
XCHG reg,reg XCHG CL,DL
XCHG mem,reg
reg,mern
10010reg
XCHG BX,DX
XCHG DH,CL
XCHG EBP,EBX
XCHG EAX,EDI
XCHG
DATAJ,CL
XCHG BYTES,CX
XCHG NUMBS,ECX
XCHG
[EAX],CX
XCHG CL,POPS
8086 4
8088 4
80286 3
80386 3
80486 3
Pentium 3
Pentium Pro
8086 17 + ea
8088 25 + ea
80286 5
80386 5
80486 5
Pentium 3
Pentium Pro
Format Example Microprocessor Clocks
XCHG acc,reg
reg.acc
XLAT Translate
11010111
XCHG BX,AX
XCHG AX,DI
XCHG DH,AL
XCHG
EDX,EAX
XCHG SI,AX
8086 3
8088 3
80286 3
80386 3
80486 3
Pentium 2
Pentium Pro
Format Example Microprocessor Clocks
XLAT XLAT
8086 11
8088 11
80286 5
80386 3

XOR Exclusive-OR
Dodatak A
80486 4
Pentium 4
Pentium Pro
000110dw oorrrmmm disp O D I T S Z A P C
0 * * ? * 0
Format Example Microprocessor Clocks
XOR reg,reg XOR CL,DL
XOR AX,DX
XOR CH,CL
XOR EAX,EBX
XOR ESI,EDI
XOR mem,reg XOR
DATAJ,CL
XOR reg,mem
XOR BYTES,CX
XOR
NUMBS,ECX
XOR [EAX],CX
XOR
CL,DATAL
XOR CX,BYTES
XOR ECX,NUMBS
XOR
DX,[EBX+EDI]
100000sw oo110mmm disp data
8086 3
8088 3
80286 2
80386 2
80486 1
Pentium 1or 2
Pentium Pro
8086 16 + aa
8088 24 + ea
80286 7
80386 6
80486 3
Pentium 1 or 3
Pentium Pro
8086 9 + ea
8088 13 + ea
80286 7
80386 7
80486 2
Pentium 1 or2
Pentium Pro
Format Example Microprocessor Clocks
XOR reg,imm XOR CX,3
XOR DI,1AH
XOR DL,34H
XOR
EDX,1345H
8086 4
8088 4
80286 3
80386 2
80486 1
A-93

XOR mem.imm
0010101w data
A-94
Zbirka zadataka iz Mikroprocesora i mikrora~unara
XOR CX,1834H
XOR DATAS,3
XOR BYTE
PTR[EDI],1AH
XOR
DADDY,34H
XOR LIST,'A'
XORTOAD,1834
H
Pentium 1or 3
Pentium Pro
8086 17 + ea
8088 25 + ea
80286 7
80386 7
80486 3
Pentium 1 or3
Pentium Pro
Format Example Microprocessor Clocks
XOR acc,imm
XOR AL,3
XOR AX,1AH
XOR EAX,34H
8086 4
8088 4
80286 3
80386 2
80486 1
Pentium 1
Pentium Pro
A.4 The instruction set of the arithmetic coprocessor
F2XM1 2 ST -1
11011001 11110000
Example Clocks
F2XM1 8087 310-630
FABS Absolute value of ST
11011001 11100001
80287 310-630
80387 211-476
80486/7 140-279
Pentium 13-57
Example Clocks
FABS 8087 10-17
80287 10-17
80387 22

FADD/FADDP/FIADD Addition
Dodatak A
11011000 oo000mmm disp 32-bit memory (FADD)
11011100 oo000mmm disp 64-bit memory (FADD)
11011d00 11000rrr FADD ST,ST(rrr)
11011110 11000rrr FADDP SR,ST (rrr)
11011110 oo000mmm disp 16-bit memory (FIADD)
11011010 oo000mmm disp 32-bit memory (FIADD)
80486/7 3
Pentium 1
Format Examples Clocks
FADD FADD DATA 8087 70-143
FADDP FADD ST,ST(1) 80287 70-143
FIADD FADDP 80387 23-72
FIADD NUMBER 80486/7 8-20
FADD ST,ST(3)
FADDP ST,ST(2)
FADD ST(2),ST
FCLEX/FNCLEX Clear errors
11011011 11100010
Pentium 1-7
Example Clocks
FCLEX 8087 2-8
FNCLEX 80287 2-8
FCOM/FCOMP/FCOMPP/FICOM/FICOMP Compare
11011000 oo010mmm disp 32-bit memory (FCOM)
11011100 oo010mmm disp 64-bit memory (FCOM)
11011000 11010rrr FCOM ST(rrr)
11011000 oo011 mmm disp 32-bit memory (FCOMP)
11011100 oo011 mmm disp 64-bit memory (FCOMP)
11011000 11011 rrr FCOMP ST (rrr)
11011110 11011001 FCOMPP
11011110 oo010mmm disp 16-bit memory (FICOM)
11011010 oo010mmm disp 32-bit memory (FICOM)
11011110 oo011mmm disp 16-bit memory (FICOMP)
80387 11
80486/7 7
Pentium 9
A-95

A-96
Zbirka zadataka iz Mikroprocesora i mikrora~unara
11011010 oo011mmm disp 32-bit memory (FICOMP)
Format Examples Closks
FCOM FCOM ST(2) 8087 40-93
FCOMP FCOMP, DATA 80187 40-93
FCOMPP FCOMPP 80387 24-63
FICOM FICOM NUMBER 80486/7 15-20
FICOMP FICOMP DATA3 Pentium 1-8
FCOS Cosine of ST
11011001 111111111
Example Clocks
FCOS 8087 -
FDECSTP Decrement stack pointer
11011001 11110110
80287 -
80387 123-772
80486/7 193-279
Pentium 18-124
Example Clocks
FDECSTP 8087 6-12
FDISI/FNDISI Disable interrupts
11011011 11100001
(Ignored on the 80287, 80387, 80486/7, and Pentium)
80287 6-12
80387 22
80486/7 3
Pentium 1
Example Clocks
FDISI 8087 2-8
FNDISI 80287 -
FDIV/FDIMP/FIDIV Division
11011000 oo010mmm disp 32-bit memory (FDIV)
11011100 oo100mmm disp 64-bit memory (FDIV)
11011d00 11111rrr FDIV ST,ST(rrr)
80387 -
80486/7 -
Pentium -

Dodatak A
11011110 11111rrr FDIVP ST,ST(rrr)
11011110 oo110mmm disp 16-bit memory (FIDIV)
11011010 oo110mmm disp 32-bit memory (FIDIV)
Format Examples Clocks
FDIV FDIV DATA 8087 191-243
FDIVP FDIV ST,ST(3) 80287 191-243
FIDIV FDIVP 80387 88-140
FIDIV NUMBER 80486/7 9-89
FDIV ST,ST(5)
FDIIVP ST,ST(2)
FDIV ST(2), ST
FDIVR/FDIVRP/FIDIVR Division reversed
11011000 oo111mmm disp 32-bit memory (FDIVR)
11011100 oo111mmm disp 64-bit memory (FDIVR)
11011d00 11110rrr FDIVR ST,ST(rrr)
11011110 11110rrr FDIVP ST,ST(rrr)
11011110 oo111mmm disp 16-bit memory (FIDIVR)
11011010 oo111mmm disp 32-bit memory (FIDIVR)
Pentium 39-42
Format Examples Clocks
FDIVR FDIVR DATA 8087 191-243
FDIVRP FDIVR ST,ST(3) 80287 191-243
FIDIVR FDIVRP 80387 88-140
FIDIVR NUMBER 80486/7 9-89
FDIVR ST,ST(5)
FDIIVRP ST,ST(2)
FDIVR ST(2), ST
FENI/FNENI Disable interrupts
11011011 11100000
(Ignored on the 80287, 80387, 80486/7, and Pentium)
Pentium 39-42
Example Clocks
FENI 8087 2-8
FNENI 80287 -
FFREE Free register
80387 -
80486/7 -
Pentium -
A-97

11011101 11000rrr
A-98
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Format Examples Clocks
FFREE FFREE 8087 9-16
FINCSTP Increment stack poionter
11011101 11110111
FFREE ST(1) 80287 9-16
FFREE ST(2) 80387 18
80486/8 3
Pentium 1
Example Clocks
FINCSTP 8087 6-12
FINIT/FNINIT Initialize coprocessor
11011101 11110110
80287 6-12
80387 21
80486/8 3
Pentium 1
Example Clocks
FINIT 8087 2-8
FNINIT 80287 2-8
FLD/FILD/FBLD Load data to ST(0)
11011001 oo000mmm disp 32-bit memory (FLD)
11011101 oo000mmm disp 64-bit memory (FLD)
11011011 oo101mmm disp 80-bit memory (FLD)
11011111 oo000mmm disp 16-bit memory (FILD)
11011011 oo000mmm disp 32-bit memory (FILD)
11011111 oo101mmm disp 64-bit memory (FILD)
11011111 oo100mmm disp 80-bit memory (FBLD)
80387 33
80486/8 17
Pentium 1
Format Examples Clocks
FLD FLD DATA 8087 17-310
FILD FILD DATA1 82087 17-310
FBLD FBLD DEC_DATA 83087 14-275

FLD1 Load +1.0 to ST(0)
11011101 11101000
Dodatak A
80486/7 3-103
Pentium 1-3
Example Clocks
FLD1 8087 15-21
FLDZ Load +0.0 to ST(0)
11011001 11101110
80287 15-21
80387 24
80486/7 4
Pentium 2
Examples Clocks
FLDZ 8087 11-17
FLDPI Load to ST(0)
11011001 11101011
80287 11-17
80387 20
80486/7 4
Pentium 2
Examples Clocks
FLDPI 8087 16-22
FLDL2E Load log2 e to ST(0)
11011001 11101010
80287 16-22
80387 40
80486/7 8
Pentium 3-5
Examples Clocks
FLDL2E 8087 15-21
FLDL2T Load log2 10 to ST(0)
11011001 11101001
80287 15-21
80387 40
80486/7 8
Pentium 3-5
A-99

A-100
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Examples Clocks
FLDL2T 8087 16-22
FLDLG2 Load log10 2 to ST(0)
11011001 11101000
80287 16-22
80387 40
80486/7 8
Pentium 3-5
Examples Clocks
FLDG2 8087 18-24
FLDLN2 Load loge 2 to ST(0)
11011001 11101101
80287 18-24
80387 41
80486/7 8
Pentium 3-5
Example Clocks
FLDLN2 8087 17-23
FLDCW Load control register
11011001 oo101mmm disp
80287 17-23
80387 41
80486/7 8
Pentium 3-5
Format Examples Clocks
FLDCW FLDCW DATA 8087 7-14
FLDENV Load environment
11011001 oo100mmm disp
FLDCW STATUS 80287 7-14
80387 19
80486/7 4
Pentium 7
Format Examples Clocks
FLDENV FLENV ENVIRON 8087 35-45
FLDENV DATA 80287 25-45
80387 71

FMUL/FMULP/FIMUL Multiplication
Dodatak A
11011000 oo001 mmm disp 32-bit memory (FMUL)
11011100 oo001 mmm disp 64-bit memory (FMUL)
11011d00 11001rrr FMUL ST,ST(rrr)
11011110 11001rrr FMULP ST,ST (rrr)
11011110 oo001 mmm disp 16-bit memory (FIMUL)
11011010 oo001 mmm disp 32-bit memory (FIMUL)
80486/7 34-44
Pentium 32-37
Format Examples Clocks
FMUL FMUL DATA 8087 110-168
FMULP FMUL ST,ST(2) 80287 110-168
FIMUL FMUL ST(2), ST 80387 29-82
FNOP No operation
11011001 11010000
FMULP 80486/7 11-27
FIMUL DATA3 Pentium 1-7
Examples Clocks
FNOP 8087 10-16
FPATAN Partial arctangent of ST(0)
11011001 11110011
80287 10-16
80387 12
80486/7 3
Pentium 1
Examples Clocks
FPATAN 8087 250-800
FPREM Partial remainder
11011001 11111000
80287 250-800
80387 314-487
80486/7 218-303
Pentium 17-173
Examples Clocks
FPREM 8087 15-190
80287 15-190
80387 74-155
A-101

FPREM1 Partial remainder(IEEE)
11011001 11110101
A-102
Zbirka zadataka iz Mikroprocesora i mikrora~unara
80486/7 70-138
Pentium 16-64
Examples Clocks
FPREM1 8087 -
FPTAN Partial tangent of ST(0)
11011001 11110010
80287 -
80387 95-185
80486/7 72-167
Pentium 20-70
Examples Clocks
FPTAN 8087 30-450
FRNDINT Round ST(0) to an integer
11011001 11111100
80287 30-450
80387 191-497
80486/7 200-273
Pentium 17-173
Examples Clocks
FRNDINT 8087 16-50
FRSTOR Restore state
11011101 oo110 mmm disp
80287 16-50
80387 66-80
80486/7 21-30
Pentium 9-20
Format Examples Clocks
FRSTOR FRSTOR DATA 8087 197-207
FSAVE/FNSAVE Save machine state
11011101 oo110 mmm disp
FRSTOR STATE 80287 197-207
FRSTOR MACHINE 80387 308
80486/7 120-131
Pentium 70-95

Dodatak A
Format Examples Clocks
FSAVE FSAVE STATE 8087 197-207
FNSAVE FNSAVE STATUS 80287 197-207
FSCALE Scale ST(0) by ST(1)
11011001 11111101
FSAVE MACHINE 80387 375
80486/7 143-154
Pentium 124-151
Examples Clocks
FSCALE 8087 32-38
FSETPM Set protected mode
11011011 11100100
80287 32-38
80387 67-86
80486/7 30-32
Pentium 20-31
Examples Clocks
FSETPM 8087 -
FSIN Sine of ST(0)
11011001 11111110
80287 2-18
80387 12
80486/7 -
Pentium -
Examples Clocks
FSINN 8087 -
FSINCOS Find sine and cosine of ST(0)
11011001 11111011
80287 -
80387 122-771
80486/7 193-279
Pentium 16-126
Examples Clocks
FSINCOS 8087 -
80287 -
80387 194-809
A-103

FSQRT Square root of ST(0)
11011001 11111010
A-104
Zbirka zadataka iz Mikroprocesora i mikrora~unara
80486/7 243-329
Pentium 17-137
Examples Clocks
FSQRT 8087 180-186
FST/FSTP/FIST/FISTP/FBSTP Store
80287 180-186
80387 122-129
80486/7 83-87
Pentium 70
11011001 oo010 mmm disp 32-bit memory (FST)
11011101 oo010 mmm disp 32-bit memory (FST)
11011101 11010 rrr FST ST(rrr)
11011011 oo011 mmm disp 32-bit memory (FSTP)
11011011 oo011 mmm disp 64-bit memory (FSTP)
11011101 oo111 mmm disp 32-bit memory (FSTP)
11011111 11001 rrr FSTP ST(rrr)
11011001 oo010 mmm disp 16-bit memory (FIST)
11011011 oo010 mmm disp 32-bit memory (FIST)
11011111 oo011 mmm disp 16-bit memory (FISTP)
11011011 oo011 mmm disp 32-bit memory (FISTP)
11011111 oo111 mmm disp 64-bit memory (FISTP)
11011111 oo110 mmm disp 80-bit memory (FBSTP)
Format Examples Clocks
FST FST DATA 8087 15-540
FSTP FST ST(3) 80287 15-540
FIST FST 80387 11-534
FISIT FSTP 80486/7 3-176
FBSTP FIST DATA2 Pentium 1-3
FBSTP DATA6
FISTP DATA8
FSTCW/FNSTCW Store control register
11011001 oo111 mmm disp
Format Examples Clocks
FSTCW FSTCW CONTROL 8087 12-18

Dodatak A
FNSTCW FNSTCW STATUS 80287 12-18
FSTCW MACHINE 80387 15
FSTENV/FNSTENV Store environment
11011001 oo110 mmm disp
80486/7 3
Pentium 2
Format Examples Clocks
FSTENV FSTENV CONTROL 8087 40-50
FNSTENV FNSTENV STATUS 80287 40-50
FSTENV MACHINE 80387 103-104
FSTSW/FNSTSW Store status register
11011101 oo111 mmm disp
80486/7 58-67
Pentium 48-50
Format Examples Clocks
FSTSW FSTSW CONTROL 8087 12-18
FNSTSW FNSTSW STATUS 80287 12-18
FSTSW MACHINE 80387 15
FSTSW AX 80486/7 3
FSUB/FSUBP/FISUB Subtraction
11011000 oo100 mmm disp 32-bit memory (FSUB)
11011100 oo100 mmm disp 64-bit memory (FSUB)
11011d00 11101 rrr FSUB ST,ST(rrr)
11011110 11101 rrr FSUBP ST,ST(rrr)
11011110 oo100 mmm disp 16-bit memory (FISUB)
11011010 oo100 mmm disp 32-bit memory (FISUB)
Pentium 2-5
Format Examples Clocks
FSUB FSUB DATA 8087 70-143
FSUBP FSUB ST,ST(2) 80287 70-143
FISUB FSUB ST(2), ST 80387 29-82
FSUBP DATA3 80486/7 8-35
FSUBP Pentium 1-7
FSUBR/FSUBRP/FISUBR Reverse subtraction
11011000 oo101 mmm disp 32-bit memory (FSUBR)
11011100 oo101 mmm disp 64-bit memory (FSUBR)
11011d00 11100 rrr FSUBR ST,ST (rrr)
A-105

A-106
Zbirka zadataka iz Mikroprocesora i mikrora~unara
11011110 11100 rrr FSUBRP ST,ST(rrr)
11011110 oo101 mmm disp 16-bit memory (FISUBR)
11011110 oo101 mmm disp 32-bit memory (FISUBR)
Format Examples Clocks
FSUBR FSUBR DATA 8087 70-143
FSUBRP FSUBR ST, ST(2) 80287 70-143
FISUBR FSUBR ST(2), ST 80387 29-82
FSUBRP 80486/7 8-35
FISUBR DATA3 Pentium 1-7
FTST Compare ST(0) with + 0.0
11011001 11100100
Examples Clocks
FTST 8087 38-48
FUCOM/FUCOMP/FUCOMPP Unordered compare
11011101 11100 rrr FUCOM ST,ST(rrr)
11011101 11101 rrr FUCOMP ST,ST(rrr)
11011101 11101001 FUCOMPP
80287 38-48
80387 28
80486/7 4
Pentium 1-4
Format Examples Clocks
FUCOM FUCOM ST,ST(2) 8087 -
FUCOMP FUCOM 80287 -
FUCOMPP FUCOMP ST, ST(3) 80387 24-26
FWAIT Wait
10011011
FUCOMP 80486/7 4-5
FUCOMPP Pentium 1-4
Examples Clocks
FWAIT 8087 4
FXAM Examine ST(0)
11011001 11100101
80287 3
80387 6
80486/7 1-3
Pentium 1-3

Dodatak A
Examples Clocks
FXAM 8087 12-23
FXCH Exchange ST(0) with another register
11011001 111001 rrr FXCH ST, ST(rrr)
80287 12-23
80387 30-38
80486/7 8
Pentium 21
Format Examples Clocks
FXCH FXCH ST,ST(1) 8087 10-15
FXCH 80287 10-15
FXCH ST,ST(4) 80387 18
FXTRACT Extract components of ST(0)
10011011 11110100
80486/7 4
Pentium 1
Examples Clocks
FXTRACT 8087 27-55
FYL2X ST(1) x log/2 ST(0)
11011001 11110001
80287 27-55
80387 70-76
80486/7 16-20
Pentium 13
Examples Clocks
FYL2X
FXL2XP1 ST(1) * log2 [ST(0) + 1.0]
11011001 11111001
8087 900-1100
80287 900-1100
80387 120-538
80486/7 196-329
Pentium 22-111
Examples Clocks
FXL2XP1
8087 700-1000
80287 700-1000
80387 257-547
80486/7 171-326
A-107

A-108
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Pregled instrukcija mikroprocesora iz familije 80x86
Pentium 22-103
U tekstu koji sledi dat je evolutivni pregled instrukcija mikroprocesora 80x86 po~ev od 8086 do Pentium-a.
Skup instrukcija ~ini {est glavnih grupa instrukcija.
1. Instrukcije za prenos podataka
Instrukcije iz ove grupe se koriste za kopiranje podataka izmedju registara, memorije i spoljnjeg sveta.
Takodje, neke od instrukcija manipuli{u magacinom, dok se druge mogu koristiti za promenu vrednosti
markera uslova.
Instrukcije za prenos podataka su:
IN Input byte or word from port
LAHF
Load AH from flags
LDS Load pointer using data segment
LEA Load effective address
LES Load pointer using extra segment
MOV Move to/from register/memory
OUT Output byte or word to port
POP Pop word off stack
POPF Pop flags off stack
PUSH Push word onto stack
PUSHF Push flags onto stack
SAHF Store AH into flags
XCHG Exchange byte or word
CLAT Translate byte
Dodatne 80286 instrukcije:
INS
Input string from port
OUTS Ouput string to port
POPA Pop all registers
PUSHA Push all registers

Dodatne 80386 instrukcije:
LFS
Load pointer using FS
LGS Load pointer using GS
LSS Load pointer using SS
MOVSX Move with sign extended
MOVZX Move with zero extended
POPAD Pop all double (32-bit) registers
POPD Pop double register
POPFD Pop double flag register
PUSHAD Push all double registers
PUSHD Push double register
PUSHFD Push double flag register
Nova 80486 instrukcija:
BSWAP Byte swap
Nova Pentium instrukcija:
MOV Move to/from control register
2. Aritmeti~ke instrukcije
Dodatak A
Skoro sve instrukcije iz ove grupe manipuli{u nad podacima tipa bajt ili re~. Pored operacija sabiranja i
oduzimanja, postoje i instrukcije za mno`enje i deljenje. Operacije sabiranja i oduzimanja se mogu izvr{avati
nad binarnim i BCD operandima.
Aritmeti~ke instrukcije su:
AAA
ASCII adjust for addition
AAD ASCII adjust for division
AAM ASCII adjust for multiply
AAS ASCII adjust for subtraction
ADC Add byte or word plus carry
ADD Add byte or word
CBW Convert byte or word
CMP Compare byte or word
A-109

CWD Convert word to double-word
DAA Decimal adjust for addition
DAS Decimal adjust for subtraction
DEC Decrement byte or word by one
DIV Divide byte or word (unsigned)
IDIV Integer divide byte or word
IMUL Integer multiply byte or word
INC Increment byte or word by one
MUL Multiply byte or word (unsigned)
NEG Negate byte or word
SBB Subtract byte or word and carry
SUB Subtract byte or word
Dodatne 80386 instrukcije:
DCQ
A-110
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Convert double word to quad word
CWDE Convert word to dobule word
Dodatne 80486 instrukcije:
CMPXCHG
Compare and exchange
XADD Exchange and add
Nova Pentium instrukcija:
CMPXCHG8B
Compare and exchange 8 bytes
3. Instrukcije koje manipuli{u sa bitovima
Instrukcije koje su u stanju da obavljaju logi~ke operacije, operacije pomeranja i rotiranja, pripadaju ovoj
grupi. Veliki broj Bulovih operacija (AND, OR, NOT, ...) pripadaju logi~kim instrukcijama. Ove, kao i
instrukcije pomeranja i rotiranja, operi{u nad bajtovima ili re~ima. Kod mikroprocesora 80386 pa navi{e,
postoje instrukcije koje manipuli{u nad sadr`ajem jedinstvenog bita.
Instrukcije koje manipuli{u sa bitovima su:
AND
Logical AND of byte or word
OR Logical OR of byte or word

RCL Rotate left through carry byte or word
ROL Rotate left byte or word
ROR Rotate right byte or word
SAL Arithmetic shift left byte or word
SAR Arithmetic shift right byte or word
SHR Logical shift right byte or word
SHL Logical shift left byte or word
TEST Test byte or word
XOR Logical exclusive-OR of byte or word
Dodatne 80386 instrukcije:
BSF
Bit scan forward
BSR Bit scan reverse
BT Bit test
BTC Bit test and complement
BTR Bit test and reset
BTS Bit test and set
SHLD Shift left double precision
SHRD Shift right double precision
SETcc Set byte on condition
4. Instrukcije za manipulaciju sa nizovima
Dodatak A
Komande koje izdaje korisnik kao i odgovaraju}i odzivi, naj~e{}e se kodiraju kao niz ASCII znakova koji se
mogu procesirati korektnim izborom instrukcija koje manipuli{u sa nizovima.
Instrukcije koje manipuli{u sa nizovima su:
CMPS
Compare byte or word string
LODS Load byte or word string
MOVS Move byte or word string
MOVSB(MOVSW) Move byte string(word string)
REP Repeat
REPE (REPZ) Repeat while equal (zero)
REPNE (REPNZ) Repeat while not equal (not zero)
SCAS Scan byte or word string
SSTOS Store byte or word string
A-111

5. Instrukcije za upravljanje tokom programa
A-112
Zbirka zadataka iz Mikroprocesora i mikrora~unara
U ovu grupu spadaju sve instrukcije tipa jump, loop, call, interrupt call. Najve}i deo instrukcija tipa jump su
uslovne instrukcije grananja koje testiraju postavljenost (stanje) markera uslova.
Programsko-upravlja~ke instrukcije su:
CALL
INT Interrupt
Call procedure (subroutine)
INTO Interrupt if overflow
IRET Return from interrupt
JA (JNBE) Jump if above (not below nor equal)
JAE (JNB) Jump if above or equal (not below)
JB (JNAE) Jump if below (not above nor equal)
JBE (JNA) Jump if below or equal (not above)
JC Jump if carry set
JCXZ Jump if CX equals zero
JE (JZ) Jump if equal (zero)
JG (JNLE) Jump if greater (not less nor equal)
JGE (JNL) Jump if greater or equal (not less)
JL (JNGE) Jump if less (not greater nor equal)
JLE (JNG) Jump if less or equal (not greater)
JMP Unconditional jump
JNC Jump if no carry
JNE (JNZ) Jump if not equal (not zero)
JNO Jump if no overflow
JNP (JPO) Jump if no parity (parity odd)
JNS Jump if no sign
JO Jump if overlow
JP (JPE) Jump if no parity (parity even)
JS Jump if sign
LOOP Loop unconditional
LOOP (LOOPZ) Loop if equal (zero)
LOOPNE
(LOOPNZ)
Loop if not equal (not zero)
RET Return from procedure (subroutine)

Dodatne 80286 instrukcije:
BOUND
Check index against array bounds
ENTER Enter a procedure
LEAVE Leave a proceure
Dodatne 80386 instrukcije:
IRETD
Interrupt return
JECXZ Jump if ECX is zero
6. Instrukcije za upravljanje radom procesora
Dodatak A
Instrukcije iz ove grupe imaju efekat na rad procesora. Ve}i broj instrukcija iz ove grupe manipuli{e sa
markerima.
Instrukcije za upravljanje radom procesora su:
CLC
Clear carry flag
CLD Clear direction flag
CLI Clear interrupt enable flag
CMC Complement carry flag
ESC Escape to external processor
HLT Halt processor
LOCK Lock bus during next instruction
NOP No operation
STC Set carry flag
STD Set direction flag
STI Set interrupt enable flag
WAIT Wait for TEST pin activity
Dodatne 80286 instrukcije (samo za za{ti}eni na~in rada):
ARPL
Adjust requested privilege level
CLTS Clear task switched flag
LAR Load access rights
LGDT Load global descriptor table
LIDT Load interrupt descriptor table
A-113

LLDT Load Local descriptor table
LMSW Load machine status word
LSL Load segment limit
LTR Load task register
SGDT Store global descriptor table
SIDT Store interrupt descriptor table
SLDT Store local descriptor table
SMSW Store machine status word
STR Store task register
VERR Verify segment for reading
VERW Verify segment for writing
Dodatne 80486 instrukcije:
INVD
A-114
Invalidate cache
INVLPG Invalidate TLB entry
WBINVD Write back and invalidate cache
Nove Pentium instrukcije:
CPUID
CPU identification
RDMSR Read from model-specific register
RDTSC
Zbirka zadataka iz Mikroprocesora i mikrora~unara
Read from time stamp counter
RSM Resume from system management
mode
WRMSR Write to model-specific register