MS DOS : .com .exe. DOS 256 (100h), (PSP - Program Segment Prefix). PSP 2.4.
2.4.
[].
| 00 - 15 | DOS |
| 16 2B | |
| 2C 2D | |
| 2E 5B | |
| 5C 7F | 1 2, DOS |
| 80 FF | . |
.com . 2.4. .com , : PSP, , . .com 64 PSP . PSP. 100h, . FFFEh.
 |
2.1. 2.2. , .com .
1.2. .com .
TITLE .com
; INCLUDE filename
; EQU =
DATASG SEGMENT Para Data
; , exCode Exit.
exCode DB 0
;
DATASG ENDS
STACKSG SEGMENT Para STACK Stack
db 100h dup(?)
STACKSG ENDS
CODESG SEGMENT Para Code
ASSUME CS:CODESG, DS:DATASG, SS:STACKSG
Start:
; , ..
MOV AH, 004Ch; DOS
MOV AL, [exCode];
INT 21h; DOS. .
END Start;
1.3. .com .
%TITLE .com
IDEAL
MODEL tiny
; INCLUDE filename
; EQU =
DATASEG
; , exCode Exit.
exCode DB 0
;
CODESEG
ORG 100h; C .com
Start:
;
Exit:
MOV AH, 004Ch; DOS
MOV AL, [exCode];
INT 21h; DOS. .
END Start;
