gfat16.asm

操作系统实验教程核心技术与编程实例书中地例子代码

;程序文件：\TC\G\GFAT16.ASM 清单
; base on g_int.asm
;only support one hard disk
.MODEL HUGE
.386P
include \tc\g\include\g_def.asm   ; 描述符结构、常量、宏定义,清单见程序1-1
include \tc\g\include\cos_def.asm ; 描述符结构、常量、宏定义,清单见程序1-1
include \tc\g\include\tos_seg.asm ; 定义TOS堆栈段TOS_STACKSEG与TOS任务状态段TOS_TSSSEG
                                  ; 清单见程序1-2
include \tc\g\include\ps_seg.asm  ; 
TOS_CODESEG SEGMENT PARA USE16    ; TOS操作系统的代码段
            ASSUME CS:TOS_CODESEG,DS:DATA,SS:TOS_STACKSEG
TOS_BEGIN:   
            COS_INIT    ; TOS任务初始处理，在包含\tc\g\include\g_def.asm文件中
            ;***********move to 2M 
            CALL SEGS_MOV_2M ;all tos_segs(6 segs) --->2M idt_m
            CALL PGT_INIT
            COS_PAGE_INIT   ;in cos_def
            ;*********** HAVE ENTERED PAGE_MODE

            CALL DISP_COS_HEAD   ;IN gfat_p.ASM
            ; setup cursor
            MOV BH,0
            MOV DX,0000H
            MOV AH,2
            INT 80H

TOS_BEGIN_CMD:
            ;; begin command line mode
            ;;;;;;            display "C:\>"
            ; read cursor
            MOV AH,03H 
            MOV BH,0
            INT 80H
            ; set cursor
            MOV AH,02H 
            MOV BH,0
            INC DH
            MOV DL,0
            INT 80H

            MOV AX,V_TOS_DATA_SEL 
            MOV DS,AX
            MOV DX,OFFSET COS_FLAG
            CALL STRDISP           ;display "C:\>"

            ;;;;;;;;;;;;;;;;set "C:\" as current directory
            CALL FILE_INIT
            MOV AX,V_TOS_DATA_SEL 
            MOV DS,AX
            CMP AL,1     ;AL=1 is not FAT16
            JE  PAGE_END

            ;input str    --->G_WORK (  ASCIIZ_STRING)
            MOV AX,V_TOS_DATA_SEL  
            MOV DS,AX
            MOV DX,OFFSET G_WORK
            MOV AL,255     ;MAX COUNT
            MOV AH,0AH     ;=DOS 21H0AH
            INT 21H                ;input string in current position
            CALL DO_CMD
            CMP AL,0       ;=0 OK&NEXT =1 EXIT =2 ERROR 
            JE  TOS_BEGIN_CMD
            CMP AL,1
            JE  PAGE_END

            ;=2 ERROR  display command error
            ; read cursor
            MOV AH,03H 
            MOV BH,0
            INT 80H
            ; set cursor
            MOV AH,02H 
            MOV BH,0
            INC DH
            MOV DL,0
            INT 80H
            ; display ASCIIZ string
            MOV AX,V_TOS_DATA_SEL 
            MOV DS,AX
            MOV DX,OFFSET CMD_ERROR
            CALL STRDISP
            JE  PAGE_END

TOS_BEGIN_CMD_R:

            ;;;;;;;;;;;;;;;;;;;;;;;; copy g_work-->str
            ;MOV AX,V_TOS_DATA_SEL  ;INPUT STRING IN CURRENT POSITION
            ;MOV DS,AX
            ;MOV DX,OFFSET STR1
            ;PUSH DX
            ;PUSH DS
            ;MOV BX,OFFSET G_WORK
            ;INC BX
            ;INC BX                ;from 3 copy
            ;PUSH BX
            ;PUSH DS
            ;DEC BX
            ;MOV AL,DS:[BX]
            ;INC AL
            ;MOV AH,0
            ;PUSH AX
            ;CALL STRNCPY           ;G_WORK--->STR1

            ;strcpy    ASCIIZ str1-->str2
            ;MOV AX,V_TOS_DATA_SEL  
            ;MOV DS,AX
            ;MOV DX,OFFSET STR2
            ;PUSH DX
            ;PUSH DS
            ;MOV DX,OFFSET STR1
            ;PUSH DX
            ;PUSH DS
            ;CALL STRCPY
            
;;
            ;MOV AX,V_TOS_DATA_SEL  ;display g_work
            ;MOV DS,AX
            ;MOV DX,OFFSET G_WORK
            ;INC DX
            ;INC DX
            ;MOV AH,09H     ;=DOS 21H09H
            ;INT 21H

            ;MOV AX,G_VRAM_SEL
            ;MOV ES,AX
            ;MOV AL,41H  ;"A"
            ;MOV AH,41H
            ;MOV ES:500,AX

COMEBACK_TO_TOS:             ; 21h---4ch return
            JMP PAGE_END
ERR_EXEFIL:
            MOV AH,9
            MOV CX,1100H 
            MOV DX,OFFSET ERR_EXEFILE
            INT 21H    
PAGE_END:   ;*********************     should have  next 3 lines   
            DB 0EAH
            DW OFFSET TURN_TO_REAL_MODE
            DW TOS_CODE_SEL
TURN_TO_REAL_MODE:
            MOV EAX,CR0 ;  ；关闭分页模式
            AND EAX,7FFFFFFFH
            MOV CR0,EAX
            JMP SHORT FROM_PAGE
FROM_PAGE:
            CALL TURN_TO_REAL      ;返回实模式，在\tc\g\include\tos_used.asm;中
            include \tc\g\include\COS_USED.ASM ;
            include \tc\g\include\V86_USED.ASM ;
            include \tc\g\include\GFAT16_P.ASM ;
sched       proc far                           ;not used
            ret
sched       endp
make_exe    proc far                           ;not used
            ret
make_exe    endp
fork        proc far                           ;not used
            ret
fork        endp
TOS_CODELEN = $
TOS_CODESEG ENDS
            include \tc\g\include\COS_GDT.ASM ;
            include \tc\g\include\COS_DATA.ASM ;
            include \tc\g\include\COS_IDT.ASM ;
            include \tc\g\include\v86_seg.asm
;*************************************************next DOS
CODE        SEGMENT PARA USE16 ;PUBLIC 'CODE'  ;实模式代码段

            ASSUME CS:CODE,DS:DATA,SS:STACK
MAIN        PROC FAR
START:      
            REAL_PAGE_INIT  ;in cos_def.asm 
            CALL V86_IDT_INIT  ;in V86_REAL.ASM
            ;在\tc\g\include\g_def.asm中，见程序1-1
TURN_TO_PROTECT_MODE:
            CALL GDT_INIT       ;初始化GDT表，在\tc\g\include\g_real.asm中，见程序1-2

            MOV AX,V86LDTSEG
            CALL USER_Px_LDT_INIT ;in px_ldt.asm

            cli
            TURN_TO_PROTECT_PAGE  
            ;*****进入TOS任务，在\TC\G\INCLUDE\G_DEF.ASM中，见程序1-1
REAL_MODE:  
            TO_DOS      ;回到DOS 在\TC\G\INCLUDE\G_DEF.ASM中，见程序1-1
MAIN        ENDP
            include \tc\g\include\g_real.asm
            include \tc\g\include\V86_REAL.ASM      ;见程序1-1
            include \tc\g\include\a20.asm      ;见程序1-1
            include \tc\g\include\PX_LDT.ASM      ;见程序1-1
tsrline     label byte
CODE        ENDS
            include \tc\g\include\DOS_DATA.ASM   
END START