.Notice - Last Update:1988/07/09 17:30 Importance Notice: The information contained in this option are for quick reference only. The accuracy of it should be based on your language manual. Set Up By : Kuang H. Tseng Language : MACRO ASSEMBLER(5.0) by Microsoft(R) . 1. Language Elements Character Sets A-Z, a-z, 0-9, ? @ _ $ : . [ ] ( ) < > { } + - / * & % ! ' ~ | \ = # ^ ; , ` " Data fields - (refer to separate key line for more detail) Constants - (refer to separate key line for more detail) Keywords Comments - after special character ';' Tokens Identifiers - (refer to separate key line for more) Macros Instructions - (refer to separate key line for more) Operators - (refer to separate key line for more) Declarations Program Line Compiler Directives - (refer to separate key line for more) Compiler Options - (refer to separate key line for more) . 2. Data fields DB (byte) - 1 byte DW (word) - 2 bytes DD (doubleword) - 4 bytes DF (farword) - 6 bytes DQ (quadword) - 8 bytes DT (tenbytes) - 10 bytes . 3.1 Identifiers (symbols/names/labels) - Alphabetic letters A to Z, digits 0 to 9, special characters ? . @ _ $ (but ? or $ can not stand alone as identifier) - The first character must be an alphabetic letter, a special character or . - Default is case insensitive but can be overruled with compiler option - Up to 31 characters are significant . 3.2 Predefined Equate Symbols @Code - alias equate for .CODE segment name @CodeSize - numeric equate indicates code memory model,0/1/2 @CurSeg - current segment name @Data - alias equate for .DATA data group name @DataSize - numeric equate that indicates the data memory model @FarData - alias equate for initialized far data segment name @FarData? - alias equate for uninitialized far data segment name @FileName - current source file . 3.3 Constants Integers Binary - radix specifier B, i.e., 01011010B Octal - radix specifier Q or O Decimal - radix specifier D Hexadecimal - radix specifier H, number start with a decimal digit Packed binary coded decimals Real numbers - consist of an integer part,a fractional part and an exponent Strings - consist of one or more ASCII characters enclosed in ' or " . 4.1. Operators Arithmetic Operator + addition - subtraction/negative unary * multiplication / integer division MOD remainder(modulus) Index Operator [] addition Shift Operator SHR SHL Logical Operators NOT bitwise complement AND bitwise AND OR bitwise inclusive OR XOR bitwise exclusive OR Relational Operators EQ true if equal NE true if not equal LT true if less than LE true if less than and equal GT true if greater than GE true if greater and equal Segment Override Operator : address relative to a specific segment Type Operator PTR SHORT THIS HIGH/LOW OFFSET SEG .TYPE TYPE LENGTH SIZE . 4.2. Operator Precedence LENGTH,SIZE,WIDTH,MASK,(),[],<> . : PTR,OFFSET,SEG,TYPE,THIS HIGH,LOW +,- *,/,MOD,SHL,SHR +,-(binary) EQ,NE,LT,LE,GT,GE NOT AND OR,XOR SHORT,.TYPE . 5.1. List of Instructions (all processors) by Name & Description in Name order AAA - ASCII adjust after addition AAD - ASCII adjust before division AAM - ASCII adjust after multiply AAS - ASCII adjust after subtraction ADC - add with carry ADD - add AND - logical and CALL - call procedure CBW - convert byte to word CLC - clear carry flag CLD - clear direction flag CLI - clear interrupt flag CMC - complement carry flag CMP - compare two operands CMPS/CMPSB/CMPSW/CMPSD - compare string CWD - convert word to double DAA - decimal adjust after addition DAS - decimal adjust after subtraction DEC - decrement DIV - unsigned divide ESC - escape HLT - halt IDIV - signed divide IMUL - signed multiply IN - input from port INC - increment INT - interrupt IINTO - interrupt on overflow IRET/IRETD - interrupt return JA/JNBE - jump if above/not below or equal JB/JNAE - jump if below/not above or equal (unsigned comparisons) JAE/JNB - jump if above or equal/not below (unsigned comparisons) JBE/JNA - jump if below or equal/not above (unsigned comparisons) JE/JZ - jump if equal(zero) JNE/JNZ - jump if not equal(not zero) JL/JNGE - jump if less/not greater or equal (signed comparisions) JGE/JNL - jump if greater/not less or equal (signed comparisions) JLE/JNG - jump if less or equal/not greater (signed comparisions) JG/JNLE - jump if greater/not less or equal (signed comparisions) JS - jump if sign JNS - jump if not sign JC - jump if carry JNC - jump if not carry JO - jump if overflow JNO - jump if not overflow JP/JPE - jump if parity/parity even JNP/JPO - jump if no parity/parity odd JCXZ/JECXZ -jump if CX is zero JMP - jump unconditionally LAHF -load flags into AH register LDS/LES/LFS/LGS/LSS - load far pointer LEA - load effective address LES/LFS/LGS - load far pointer to extra segment LOCK - lock the bus LODS/LODSB/LODSW/LODSD - load string operand LOOP - loop LOOPE/LOOPZ - loop if equal LOOPNE/LOOPNZ - loop if not equal LSS - load far pointer to stack segment MOV - move data MOVS/MOVSB/MOVSW/MOVSD - move string data MUL - unsigned multiply NEG - two's complement negation NOP - no operation NOT - one's complement negation OR - inclusive or OUT - output to port POP - pop POPF/POPFD - pop flags PUSH - push PUSHF/PUSHFD - push flags RCL/RCR/ROL/ROR - rotate REP MOVS/MOVSB/MOVSW - repeat string move REP STOS/STOSB/STOSW - repeat store string REPE/REPZ CMPS/CMPSB/CMPSW - repeat compare string while equal REPE/REPZ SCAS/SCASB/SCASW - repeat scan string while equal REPNE/REPNZ CMPS/CMPSB/CMPSW - repeat compare string while not equal REPNE/REPNZ SCAS/SCASB/SCASW - repeat scan string while not equal RET/RETN/RETF - return from procedure ROL/ROR - rotate SAHF - store ah into flags SAL/SAR/SHL/SHR - shift SBB - subtract with borrow SCAS/SCASB/SCASW/SCASD - scan string flags STC - set carry flag STD - set direction flag STI - set interrupt flag STOS/STOSB/STOSW/STOSD - store string data SUB - subtract TEST - logical compare WAIT - wait XCHG - exchange XLAT/XLATB - translate XOR - exclusive or . 5.2. List of Instructions (80186-80386) by Name & Description in Name order BOUND - check array bounds ENTER - make stack frame INS/INSB/INSD/INSW - input from port to string LEAVE - terminate stack frame initialized by ENTER instruction OUTS/OUTSB/OUTSD/OUTSW - output a string to a port PUSHA - push all general-purpose registers onto stack POPA - pop the top 16 bytes of the stack onto DI,SI,BP,SP,BX,DX,CX,AX . 5.3. List of Instructions (80286-80386) by Name & Description in Name order ARPL - adjust requested CLTS - clear task switched flag LAR - load access rights LGDT/LIDT/LLDT - load descriptor table LMSW - load machine status word LSL - load segment limit LTR - load task register SGDT/SIDT/SLDT - store descriptor table SMSW - store machine status word STR - store task register VERR/VERW - verify read or write . 5.4. List of Instructions (80386 only) by Name & Description in Name order BSF/BSR - bit scan BT/BTC/BTR/BTS - bit tests CDQ - convert doubleword to quadword CMPSD - compare string in doubleword data element size CWDE - convert word to extended double INSD - input from port to string in doubleword data element size IRETD - interrupt return JECXZ - jump if CX is zero LFS/LGS/LSS - load far pointer to stack segment LODSD - load string operand in doubleword data element size MOVSD - move string data in doubleword data element size MOVSX - move with sign-extend MOVZX - move with zero-extend OUTSD - output string to port in doubleword data element size POPFD - pop flags into the 32-bit flags register POPAD - pop 32-bit registers of AX,CX,DX,BX,SP,BP,DI PUSHAD - push 32-bit registers of AX,CX,DX,BX,SP,BP,SI,DI PUSHFD - push the 32-bit flags register SCASD - scan string in doubleword data element size SETA - set if above SETAE - set if not above or equal SETB - set if below SETC - set if carry SETE - set if equal/zero SETG - set if greater SETGE - set if not greater or equal SETL - set if less SETLE - set if less or equal SETNA - set if not above SETNAE - set if not above or equal SETNB - set if not below SETNBE - set if not below or equal SETNC - set if not carry SETNE - set if not equal SETNG - set if not greater or equal SETNGE - set if not greater or equal SETNL - set if not less SETNLE - set if not less or equal SETNO - set if not overflow SETNP - set if not parity SETNS - set if not sign SETNZ - set if not zero SETO - set if overflow SETP - set if parity SETPE - set if parity even SETS - set if sign SETZ - set if zero SHLD/SHRD - double precision shift STOSD - store string data in doublewod data element size . 5.5. List of Instructions (8087-80387) by Name & Description in Name order F2XM1 - 2^X-1 FABS - absolute value FADD/FADDP/FIADD - add FCHS - change sign FCLEX/FNCLEX - clear exceptions FCOM/FCOMP/FCOMPP/FICOM/FICOMP - comapar FDECSTP - decrement stack pointer FDISI/FNDISI - disable interrupts FDIV/FDIVP/FIDIV - divide FDIVR/FDIVRP/FIDIVR - divide reversed FENI/FNENI - enable interrupts FFREE - free register FIST/FISTP - store integer FLD/FILD/FBLD - load FLDCW - load control word FLDENV - load environment state FINCSTP - increment stack pointer FINIT/FNINIT - initialize coprocessor FLD1/FLDZ/FLDPI/FLDL2E/FLDL2T/FLDLG2/FLDLN2 - load constant FMUL/FMULP/FIMUL - multiply FNOP - no operation FPATAN - partial arctangent FPREM - partial remainder FPTAN - partial tangent FRNDINT - round to integer FRSTOR - restore saved state FSAVE/FNSAVE - save coprocessor state FSCALE - scale FSQRT - square root FST/FSTP/FIST/FISTP/FBSTP - store FSTCW/FNSTCW - store control word FSTENV/FNSTENV - store environment state FSTSW/FNSTSW - store status word FSUB/FSUBP/FISUB - subtract FSUBR/FSUBRP/FISUBR - subtract reversed FWAIT - wait FXAM - examine FXCH - exchange registers FXTRACT - extract exponent and significand FYL2X - Y log2(X) FYL2XP1 - Y log2(X+1) . 6.1. EXE program structure TITLE progname .MODEL SMALL .DATA EXTRN ?:BYTE .CODE PUBLIC progname progname proc ret progname endp END . 6.2. COM program structure TITLE pgmname CODESEG SEGMENT PARA PUBLIC 'CODE' ASSUME CS:CODESEG,DS:CODESEG,ES:CODESEG,SS:CODESEG ORG 0100H BEGIN: JMP PGM_START ; enter variables here VAR1 DB ? PGM_START: ; enter logic here MOV VAR1,0 RET CODESEG ENDS END BEGIN . 7.1 Sample of Main Program ; sample 1 title program1 DOSSEG ;Use Microsoft segment convention cr EQU 0dh ;carriage return lf EQU 0ah ;linefeed .MODEL SMALL .STACK 64 .DATA messg DB 'Welcome to MASM Assembler programming with kEDITOR',cr,lf,'$' .CODE start: mov ax,@DATA ;load segment address to ds mov ds,ax mov dx,OFFSET messg mov ah,09h int 21h mov ax,4C00h ;AH=4Ch (DOS Exit function),AL=0 error free int 21h END start . 7.2 Sample of Main Program calling a Subprogram ; sample 2 title program2 DOSSEG ;Use Microsoft segment convention cr EQU 13 ;carriage return lf EQU 10 ;linefeed .MODEL SMALL .STACK 64 .DATA messg DB 'Sample program - Calling subprograms',cr,lf len_mess EQU $-messg .CODE start: mov ax,@DATA ;load segment address to ds mov ds,ax call messout ;calling subprogram messout call done ;calling subprogram done messout proc mov bx,1 ;file handle 1 for standard output mov cx,len_mess mov dx,OFFSET messg mov ah,40h int 21h ret messout endp done proc mov ax,4C00h ;AH=4Ch (DOS Exit function),AL=0 error free int 21h done endp END start . 7.3 Sample of Macro Writing ; sample 3 title program3 DOSSEG ;Use Microsoft segment convention .MODEL SMALL .STACK 64 DOSCALL MACRO intno mov ah,intno int 21h ENDM .DATA cr EQU 13 ;carriage return lf EQU 10 ;linefeed messg DB 'Sample program - Macro Writing',cr,lf len_mess EQU $-messg .CODE start: mov ax,@DATA ;load segment address to ds mov ds,ax mov bx,1 ;file handle 1 for standard output mov cx,len_mess mov dx,OFFSET messg DOSCALL 40h ;use macro definition DOSCALL mov al,0 ;error free DOSCALL 4Ch END start . 7.4 Sample 1 of String Copying Processing str1 DB 'Sample program - String Handling',cr,lf str1len EQU $-str1 str2 DB 50 DUP(' ') ... cld mov si,offset str1 mov di,offset str2 mov cl,str1len xor ch,ch shr cx,1 jnc moveword movsb moveword: rep movsw . 7.5 Sample 2 of String Copying Processing cld ;move/copy string from string1 to string2 lea si,string1 lea di,string2 mov cx,len_str1 rep movsb mov cx,len_str1 mov dx,OFFSET string2 . 7.6 Sample of String Searching Processing cld ;use of scasb to scan mov cx,len_str2 lea di,string2 mov al,'l' ;scan string2 for 'l' repne scasb jne notfnd ;not found found: mov ah,0 ;found dec di ;point back to offset of 'l' jmp short jump notfnd: mov ah,1 jump: . 7.7 Sample of Table Processing ; sample 5 title program5 DOSSEG ;Use Microsoft segment convention .MODEL SMALL .STACK 64 .DATA table DB 'MONDAY ' DB 'TUESDAY ' DB 'WEDNESDAY' DB 'THURSDAY ' DB 'FRIDAY ' DB 'SATURDAY ' DB 'SUNDAY ' NINE DB 9 table_width EQU 9 weekday DB 9 dup(" ") .CODE start: mov ax,@DATA ;load segment address to ds mov ds,ax mov es,ax lea si,table mov al,3 ;third weekday dec al mul NINE add si,ax mov cx,table_width cld lea di,weekday rep movsb ;should have 'WEDNESDAY' in weekday mov ax,4C00h ;error free int 21h END start . 7.8 Sample of Loop Processing jcx jumploop zeroloop: mov byte ptr [si],0 inc si loop zeroloop jumploop: . 7.9 Sample of Subroutine Interface with C _SumOf3 proc push bp mov bp,sp sub sp,2 mov ax,[bp+4] add ax,[bp+6] mov [bp-2],ax mov ax,[bp+8] add ax,[bp-2] mov sp,bp pop bp ret _SumOf3 endp . 8. Compiler Directives Segment SEGMENT ENDS GROUP ASSUME END Data Allocation DB DW DD DF DQ DT LABEL ALIGN EVEN ORG . 9. Compiler Options /A writes segments in alphabetical order /B sets buffer size /C specifies a cross-reference file /D creates Pass 1 listing /Dsymbol[=value] Defines assembler symbol /E creates code for emulated floating-point instructions /H lists command-line syntax and all assembler options /Ipathname sets include-file search path /L specifies an assembly-listing file /ML makes names case sensitive /MU converts names to uppercase letters /MX makes public and external names case sensitive /N suppresses tables in listing file /P checks for impure code /S writes segments in source-code order /T suppresses messages for successful assembly /V displays extra statistics to screen /W{0/1/2} sets error display level .10. BIOS Interrupts INT 05H Print the screen INT 10H 00H Set video mode 01H Set cursor size 02H Set cursor position 03H Read cursor position 04H Read light-pen position 05H Set active display page 06H Scroll window up 07H Scroll window down 08H Read character and attribute at cursor position 09H Write character and attribute at cursor 0AH Write character 0BH Set color palette 0CH Write graphics pixel dot 0DH Read graphics pixel dot 0EH Write character in teletype (TTY) mode 0FH Get current video display mode 10H Set palette registers 13H Write character string INT 11H Equipment Determination INT 12H Memory Size Determination INT 13H 00H Reset diskette system 01H Get diskette status 02H Read diskette sectors 03H Write diskette sectors 04H Verify diskette sectors 05H Format disk track INT 14H 00H Initialize serial communications port parameters 01H Send character to communications port 02H Read character from communications port 03H Get serial communications port status INT 16H 00H Read a character 01H Check if character is ready for reading 02H Get current shift status INT 17H 00H Printer output 01H Initialize printer port 02H Read printer port status INT 18H ROM BASIC entry INT 19H Bootstrap loader INT 1AH 00H Read time clock 01H Set time clock 04H Read date from time clock 05H Set date in time clock .11. DOS Interrupts INT 21H 00H Program terminate 01H Keyboard input with echo 02H Display character output 03H Auxiliary input 04H Auxiliary output 05H Printer output 06H Direct console input/output 07H Direct console input without echo 08H Character input without echo 09H Display character string 0AH Buffered keyboard input 0BH Get keyboard status 0CH Clear keyboard buffer and then input 0DH Disk reset 0EH Select default disk drive 0FH Open file 10H Close file 11H Search for first matching disk filename 12H Search for next matching disk filename 13H Delete file 14H Sequential read 15H Sequential write 16H Create file 17H Rename file 19H Get default disk drive 1AH Set disk transfer area address 1BH Get allocation table information 21H Random read 22H Random Write 23H Get file size (in record count) 24H Set random record number 25H Set interrupt vector 26H Create a new program segment prefix 27H Random block read 28H Random block write 29H Parse filename 2AH Get date 2BH Set date 2CH Get time 2DH Set time 2EH Set/reset verify switch 2FH Get disk transfer area address 30H Get MS-DOS version number 31H Terminate and stay resident 33H Get/set Ctrl-Break 35H Get interrupt vector 36H Get free disk space 38H Get/set country-dependent information 39H Make subdirectory 3AH Remove subdirectory 3BH Change current directory 3CH Create file 3DH Open file 3EH Close file 3FH Read from file or device 40H Write to file or device 41H Delete file 42H Move file pointer 43H Get/set file attributes 44H IOCTL - Device driver control 45H Duplicate file handle 46H Force handle duplication 47H Get current directory 48H Allocate memory 49H Release allocated memory 4AH Modify allocated memory block 4BH Load/execute program 4CH Terminate process with return code 4DH Get return code of subprogram 4EH Search for first match 4FH Search for next match 54H Get verify flag 56H Rename file 57H Get/set file date and time 58H Get/set allocation strategy 59H Get extended error code information 5AH Create temporary file 5BH Create new file 5CH Lock/unlock file access 62H Get PSP address INT 22H Terminate address INT 23H Control-C/Control Break address INT 24H Critical error handler address INT 25H Absolute disk read INT 26H Absolute disk write INT 27H Terminate and stay resident INT 2FH Print spool control .12. Keyboard Scan Codes Key in HEX in Dec Key in HEX in Dec Key in HEX in Dec --- ------ ------ --- ------ ------ --- ------ ------ A a 1E 30 F1 3B 59 1 02 2 B b 30 48 F2 3C 60 2 03 3 C c 2E 46 F3 3D 61 3 04 4 D d 20 32 F4 3E 62 4 05 5 E e 12 18 F5 3F 63 5 06 6 F f 21 33 F6 40 64 6 07 7 G g 22 34 F7 41 65 7 08 8 H h 23 35 F8 42 66 8 09 9 I i 17 23 F9 43 67 9 0A 10 J j 24 36 F10 44 68 0 0B 11 K k 25 37 L l 26 38 ! 02 2 Left 4B 75 M m 32 50 @ 03 3 Right 4D 77 N n 31 49 # 04 4 Up 48 72 O o 18 24 $ 05 5 Down 50 80 P p 19 25 % 06 6 Q q 10 16 ^ 07 7 Num Lock 45 69 R r 13 19 & 08 8 Scroll Lock 46 70 S s 1F 31 * 09 9 Caps Lock 3A 58 T t 14 20 ( 0A 10 Prt Sc 37 55 U u 16 22 ) 0B 11 V v 2F 47 _ - 0C 12 Home 47 71 W w 11 17 + = 0D 13 End 4F 79 X x 2D 45 | \ 2B 43 PgUp 49 73 Y y 15 21 { [ 1A 26 PgDn 51 81 Z z 2C 44 } ] 1B 27 : ; 27 39 Ins 52 82 Esc 01 1 " ', 28 40 Del 53 83 Tab 0F 15 < ,. 33 51 Ctrl 1D 29 > . 34 52 Left Shift 2A 42 Alt 38 56 ? / 35 53 Right Shift 36 54 Space Bar 39 57 ~ ` 29 41 - 4A 74 Return 1C 28 Backspace 0E 14 + 4E 78