APPENDIX B. ASSEMBLER DIRECTIVE SUMMARY

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1 APPENDIX B. ASSEMBLER DIRECTIVE SUMMARY Assembler directives are summarized alphabetically in this the contents of directive fields. The following terms are used 10 describe NOTATION Term Expression Numerical assembly; must evaluate to 8 or 16 bils on directive issued. List Series of ic val ucs or by commas. Name Null Symbol name terminilled by a space. Field must be empty or an error results. Oplab Optional label; must be terminated a colon. Parameter Dummy parameters are symbols hold pmameters (symbolic values or in the program. elsewhere String Series of any ASCII surrounded quote marks. Single quote within is shown two consecll tive quote~. Text Series of ASCII characters. Macro definitions and calls allow the use of the Character characters listed below. Function & Ampersand. Used to concatenate symbols, Angle brackets. Used to delimit text, such as I othcr del im iters. that contain.. Double semicolon. Used before a comment in a macro definition " to prevent inclusion of the comment in each macro Exclamation point (escape character). Placed before a delimiter to be passcd as a literal in an actual parameter. To pass literal exclamation point, issue' II.' % Percent sign. Precedes actual parameters to be evaluated when the macro is called. ALL MNEMONICS INTEL CORPORA TlON 8 1

2 Appendix B. Assembler Directive Summary SUMMARY OF DIRECTIVES Label Opcode Operand(s) oplab: DB exp(s} or string(s) uplab: DS expression Define 8-bit data byte(s}. Express ions must evaluate to one byte. Reserve data storage area of specified length. oplab: DW exp(.,} or string(s} oplab: ELSE null oplab: END expression oplilb: ENDIF null name EQU expression oplilb: IF expression Define 16-bit datil word(s). Strings limited to 1-2 characters. Co nditional assembly. Code between ELSE and ENDIF directives is assembled if expression in IF cliluse is FALSE. (See IF.) Terminate assembler pass. Mu st be last statement of program. Program execution starts at 'exp,' if present; otherwise, at location O. Terminate conditional assembly block. Define symbol 'name' with value 'exp.' Symbol is not redefinable. Assemble code between IF and following ELSE or ENDIF directive if 'exp' is true. orlab: ORG expression name SET expression MACRO DIRECTIVES Set location counter to 'expression.' Define symbol 'name' with vdlue 'expression.' Symbol ca n be rederined. Lobel Opcode Operand(s) null ENDM null oplab: EXITM null Terminate macro definition. Alternate terminator of macro definition. (See ENDM.) oplab: IRP dummy param,<list> Repeat inst ruction sequence, substituting one character for m 'li st' for 'dummy param' in each iteration. ALL MNEMON/CS 7974, 79 75, 7976, 7977 INTEL CORPORATION 8-2

3 Appendix B. Assembler Directive Summary Label Opcode Operund(s) oplab: IRPC dummy Pdl"rlri1,text instruction sequence, substituting one character from 'text' for in each itera lion null LOCAL label in macro definition [0 have local name MACRO dummy and definition parameter(s) to be REPT t REPT block, limes. RELOCATION DIRECTIVES Label Opcode Operand(s) ASEG null A~~emble absolute mode. instructions and data in the CSEG boundary specification Assemblc uent instructions and data in the relocatahle mode the code location counter. oplab: DSEG boundary Assemblc relocclldble mode and data in location coumer. EXTRN name(s) program module but NAME module--name program mudule., I PUBLIC defined in this module that arc t.o be available 10 other modules. STKLN the number of stack for this module. lts lo be reserved for the ALL MNEMONICS 7976, 1977 INTEL CORPORA non B 3

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5 '" GRAPHIC OR CONTROL NUL 00 SOH 01 STX 02 ETX 03 EOT 04 ENQ 05 ACK 06 BEL 07 BS 08 HT 09 LF OA VT OB FF OC CR OD SO OE SI OF DLE 10 DCl (X-ON) 11 OC2 (TAPE) 12 OC3 (XOFF\ 13 oc4 (=FAP-E-) 14 NAK 15 SYN 16 ETB 17 CAN 18 EM 19 SUB la ESC 1B FS 1C GS 1D RS le US 1 F SP 20 " # 23 $ 24 % 25 & * 2A APPEN The 8080 and 8085 usc (parity bit) reset. ASCII (HEXADECIMAL) IX C. II CHARACTER S ASCII COD lhc..even-bit ASCII with the eighth bit GRAPHIC OR CONTROL ASCII (HEXADECIMAL) GRAPHIC OR CONTROL ASCII (HEXADECIMAL) + 2B V 56 2C VI] 57 2D X 58 2E Y 59 / 2F Z 5A 0 30 [ 5B 1 31 \ 5C D 3 33 i\ (t) 5E F a b c d 64 3A 65 3B 66 /' -'- 3C D h 68 > 3E 69 I 3F i 6A 40 k 6B A 41 6C B 42 m 60 C 43 n 6E D F E 45 P 70 F 46 q 71 G H I J 4A lj 75 K 4B v 76 L 4C w 77 M 40 x 78 N 4E Y F z 7A P 50 7B Q 51 7C R 52 (ALT MODE) 7D S 53 JE T 54 DEL (RUB OUT) 7F U 55 (-1

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