Click above to get retro games delivered to your door ever month!

 Overview         Overview of the Directives and Operators
 !                Literal-Character Operator
 $                Location Counter Operand
 %                Expression Operator
 &                Substitute Operator
 *                Multiplication
 +                Addition or Unary Plus
 -                Subtraction or Unary Minus
 .                Structure Field-Name Operator
 /                Division
 :                Segment-Override Operator
 ;                Comment Operator
 ;;               Macro Comment
 ()               Parentheses
 <>               Literal-Text Operator
 []               Index Operator
 =                Create Absolute Symbol
 .186             Enable 80186 Instructions
 .286             Enable Real Mode 80286 Instructions
 .286C            Enable Real Mode 80286 Instructions
 .286P            Enable Protected Mode 80286 Instructions
 .287             Enable 80287 Instructions
 .386             Enable Real Mode 80386 Instructions
 .386C            Enable Real Mode 80386 Instructions
 .386P            Enable All 80386 Instructions
 .387             Enable 80387 Instructions
 .8086            Enable 8086 Instructions
 .8087            Enable 8087 Instructions
 ALIGN            Aligns on Specified Boundaries
 .ALPHA           Orders Segments Alphabetically
 AND              Bitwise Logical AND
 ARG              Sets Up Argument Stack                                 TASM
 ASSUME           Associate Segment with Segment Register
 AT               Define Absolute Segment
 %BIN             Sets Width of Object Code Field                        TASM
 BYTE             Align Segment on Any Byte Address
 BYTE             Data Type for 1 byte
 CATSTR           Concatenate Strings                              . MASM 5.1
 .CODE            Defines Code Segment                             . MASM 5.0
 CODESEG          Defines Code Segment                                   TASM
 COMMENT          Enter Multi-Line Comment
 COMMON           Define Overlapping Segments
 %CONDS           Shows Conditional Blocks                               TASM
 .CONST           Defines Constant Data Segment                    . MASM 5.0
 CONST            Defines Constant Data Segment                          TASM
 .CREF            Enable Cross-Reference Listings
 %CREF            Enable Cross-Reference Listings                        TASM
 %CREFALL         Lists All Symbols                                      TASM
 %CREFREF         Disables Listing of Symbols                            TASM
 %CREFUREF        List Only Unreferenced Symbols                         TASM
 %CTLS            Prints Listing Controls                                TASM
 .DATA            Define Data Segment                              . MASM 5.0
 .DATA?           Define Unitialized Data Segment                  . MASM 5.0
 DATAPTR          Forces Expression Size                                 TASM
 DATASEG          Defines Data Segment                                   TASM
 DB               Define Byte
 DD               Define Doubleword
 %DEPTH           Sets Size of Depth Field                               TASM
 DF               Define Farword
 DISPLAY          Types a String                                         TASM
 DOSSEG           Use DOS Segment Ordering
 DP               Define Six-Byte Unit                                   TASM
 DQ               Define Quadword
 DT               Define Ten-byte Unit
 DUP              Duplicate Occurrences
 DW               Define Word
 DWORD            Data Type for 4 bytes
 ELSE             Assemble If Condition Not Met
 ELSEIF           ELSE With IF
 ELSEIF1          ELSE With IF1
 ELSEIF2          ELSE With IF2
 ELSEIFB          ELSE With IFB
 ELSEIFDEF        ELSE With IFDEF
 ELSEIFDIF        ELSE With IFDIF
 ELSEIFDIFI       ELSE With IFDIFI
 ELSEIFE          ELSE With IFE
 ELSEIFIDN        ELSE With IFIDN
 ELSEIFIDNI       ELSE With IFIDNI
 ELSEIFNB         ELSE With IFNB
 ELSEIFNDEF       ELSE With IFNDEF
 EMUL             Emulate Coprocessor                                    TASM
 END              Terminate Module
 ENDIF            Terminate Conditional Block
 ENDM             Terminate Macro or Repeat Block
 ENDP             Terminate Procedure Definition
 ENDS             End Segment or Structure Definition
 EQ               Equal Relational Operator
 EQU              Create Symbol
 .ERR             Force Error
 ERR              Force Error                                            TASM
 .ERR1            Force Error during Pass 1
 .ERR2            Force Error during Pass 2
 .ERRB            Error If String Is Blank
 .ERRDEF          Error If Name Is Defined
 .ERRDIF          Error If Strings Differ
 .ERRDIFI         Case Insensitive Version of .ERRDIF
 .ERRE            Error If False
 .ERRIDN          Error If Strings Are Identical
 ERRIF            Error If True                                          TASM
 ERRIF1           Force Error During Pass 1                              TASM
 ERRIF2           Force Error During Pass 2                              TASM
 ERRIFB           Error If String Is Blank                               TASM
 ERRIFDEF         Error If Name Is Defined                               TASM
 ERRIFDIF         Error If Strings Differ                                TASM
 ERRIFDIFI        Error If Strings Differ No Case                        TASM
 .ERRIDNI         Case Insensitive Version of .ERRIDN
 ERRIFE           Error If False                                         TASM
 ERRIFIDN         Error If Strings Are Identical                         TASM
 ERRIFIDNI        Case Insensitive Version of ERRIFIDN                   TASM
 ERRIFNB          Error If String Is Not Blank                           TASM
 ERRIFNDEF        Error If Name Is Not Defined                           TASM
 .ERRNB           Error If String Is Not Blank
 .ERRNDEF         Error If Name Is Not Defined
 .ERRNZ           Error If True
 EVEN             Align on Word Boundary
 EVENDATA         Aligns Data                                            TASM
 EXITM            Immediate Macro Exit
 EXTRN            Define External
 FAR              Data Type for Label in Different Segment
 .FARDATA         Define Far Data Segment                          . MASM 5.0
 FARDATA          Define Far Data Segment                                TASM
 .FARDATA?        Define Far Uninitialized Data Segment            . MASM 5.0
 FARDATA?         Define Far Uninitialized Data Segment                  TASM
 FWORD            Data Type For 6 Bytes
 GE               Greater Than or Equal Relational Operator
 GLOBAL           Defines a Global Symbol                                TASM
 GROUP            Define Segment Group
 GT               Greater Than Relational Operator
 HIGH             Return High-Order 8 Bits
 IDEAL            Enters Ideal Mode                                      TASM
 IF               Initiate Conditional Block
 IF1              Assemble If Pass 1
 IF2              Assemble If Pass 2
 IFB              Assemble If Argument Is Blank
 IFDEF            Assemble If Name Is Defined
 IFDIF            Assemble If Arguments Differ
 IFDIFI           Case Insensitive Version Of IFDIF
 IFE              Assemble If False
 IFIDN            Assemble If Arguments Are Identical
 IFIDNI           Case Insensitive Version Of IFIDN
 IFNB             Assemble If Argument Is Not Blank
 IFNDEF           Assemble If Name Is Not Defined
 %INCL            Lists Include Files                                    TASM
 INCLUDE          Process Code from External File
 INCLUDELIB       Includes a Library
 INSTR            Finds Substring                                  . MASM 5.1
 IRP              Assemble Once for Each Parameter
 IRPC             Assemble Once for Each Character
 JUMPS            Stretches Conditional Jumps                            TASM
 LABEL            Create Variable or Label
 .LALL            List All Macro Expansions
 LARGE            Set Offset to 32 Bits                                  TASM
 LE               Less Than or Equal Relational Operator
 LENGTH           Return Length of Item
 .LFCOND          List False Conditionals
 %LINUM           Sets Width of Line Number Field                        TASM
 .LIST            Restore Source-Code Listing
 %LIST            Shows Source Lines                                     TASM
 LOCAL            Create Symbol for Use in Macro
 LOCALS           Enables Local Symbols                                  TASM
 LOW              Return Low-Order 8 Bits
 LT               Less Than Relational Operator
 MACRO            Initiate Macro Definition
 %MACS            Lists Macros                                           TASM
 MASK             Return a Bit Mask
 MASM             Enter MASM Mode                                        TASM
 MASM51           Enable MASM 5.1 Enhancements                           TASM
 MEMORY           Locate segment as last segment possible
 MOD              Modulus
 .MODEL           Sets Memory Model                                . MASM 5.0
 MODEL            Sets Memory Model                                      TASM
 MULTERRS         One-line Multiple Error Reporting                      TASM
 NAME             Assign Name to Module
 NE               Not Equal Relational Operator
 NEAR             Data Type for Label in Same Segment
 %NEWPAGE         Starts a New Listing Page                              TASM
 %NOCONDS         Disable Listing False Statements                       TASM
 %NOCREF          Disables Cross Reference Listing                       TASM
 %NOCTLS          Disables Listing of Controls                           TASM
 NOEMUL           Disables Coprocessor Emulation                         TASM
 %NOINCL          Disables Listing of Include Files                      TASM
 NOJUMPS          Disables Conditional Jump Extending                    TASM
 %NOLIST          Disables Listing                                       TASM
 NOLOCALS         Disables Local Symbols                                 TASM
 %NOMACS          Disables Listing of Macros                             TASM
 NOMASM51         Disables MASM 5.1 Enhancements                         TASM
 NOMULTERRS       Reports Only One Error Per Line                        TASM
 %NOSYMS          Disables Symbol Table Listing                          TASM
 NOT              Bitwise NOT
 %NOTRUNC         Enables Listing Wordwrap                               TASM
 NOWARN           Disables Warning(s)                                    TASM
 OFFSET           Offset of Expression
 OR               Bitwise Logical OR
 ORG              Assign Location Counter
 %OUT             Display Text during Assembly
 P186             Enable 80186 Instructions                              TASM
 P286             Enable All 80286 Instructions                          TASM
 P286N            Enable Real Mode 80286 Instructions                    TASM
 P286P            Enable Privileged 80286 Instructions                   TASM
 P287             Enable 80287 Instructions                              TASM
 P386             Enable All 80386 Instructions                          TASM
 P386N            Enable Real Mode 80386 Instructions                    TASM
 P386P            Enable Privileged 80386 Instructions                   TASM
 P387             Enable 80387 Instructions                              TASM
 P8086            Enable 8086 Instructions Only                          TASM
 P8087            Enable 8087 Instructions                               TASM
 PAGE             Align on 256-byte Boundary
 PAGE             Page Control for Listings
 %PAGESIZE        Set Listing Page Size                                  TASM
 PARA             Align on 16-byte Boundary
 %PCNT            Set Address Field Width                                TASM
 PNO87            Disables Coprocessor Instructions                      TASM
 %POPLCTL         Pop Listing Controls                                   TASM
 PROC             Initiate Procedure Definition
 PTR              Change Type of Variable
 PUBLIC           Concatenate All Like-Named Segments
 PUBLIC           Make Symbol Available to All Modules
 PURGE            Delete Macro Definition
 %PUSHLCTL        Push Listing Controls                                  TASM
 PWORD            Forces Expression To a 32-Bit Pointer                  TASM
 QUIRKS           Enable TASM to Use MASM "Bugs"                         TASM
 QWORD            Data Type for 8 bytes
 .RADIX           Set Input Radix
 RADIX            Set Input Radix                                        TASM
 RECORD           Define Record Type
 REPT             Initiate Repeat Block
 .SALL            Suppress All Macro Expansion Listings
 SEG              Return Segment Value
 SEGMENT          Initiate Segment Definition
 .SEQ             Orders Segments Sequentially
 .SFCOND          Suppress Listing of False Conditionals
 SHL              Shift Left
 SHORT            Sets Label To SHORT Type
 SHR              Shift Right
 SIZE             Return Bytes Used by Variable
 SIZESTR          Returns String Length                            . MASM 5.1
 SMALL            Set Offset to 16 Bits                                  TASM
 .STACK           Define Stack Segment                             . MASM 5.0
 STACK            Define a Stack Segment
 STACK            Define Stack Segment                                   TASM
 STRUC            Define Structure Type
 SUBSTR           Generate a Substring                             . MASM 5.1
 SUBTTL           Specify Listing Subtitle
 %SUBTTL          Specify Listing Subtitle                               TASM
 %SYMS            Enable Listing of Symbol Table                         TASM
 SYMTYPE          Return Type of an Expression                           TASM
 %TABSIZE         Set Tab Width                                          TASM
 TBYTE            Data Type for 10 bytes
 %TEXT            Set Source Field Width                                 TASM
 .TFCOND          Toggle False Conditional Listing
 THIS             Create Operand at Current Location
 TITLE            Specify Listing Title
 %TITLE           Specify Listing Title                                  TASM
 %TRUNC           Truncates Listing Fields                               TASM
 TYPE             Return Size of Type
 .TYPE            Return Mode and Scope of an Expression
 UDATASEG()       Define Uninitialized Data Segment                      TASM
 UFARDATA         Define Uninitialized Far Data Segment                  TASM
 UNION            Define a Union                                         TASM
 UNKNOWN          Removes Type Information                               TASM
 WARN             Enable Warning(s)                                      TASM
 WIDTH            Return Width in Bits
 WORD             Align on 2-byte boundary
 WORD             Data Type for 2 bytes
 .XALL            List Macro Expansions That Produce Code
 .XCREF           Suppress Cross-Reference Listings
 .XLIST           Suppress Source-Code Listing
 XOR              Bitwise Logical XOR