; ***************************************************************************** ; ; INT_21H.ASM [ TRDOS INT 21h Handler ] ; Copyright (C) 2005 Erdogan TAN [ 29/01/2005 ] Last Update: 14/11/2009 ; ; TRDOS.ASM (include INT_21H.ASM) ; ; ***************************************************************************** ; TRDOS Function Calls trdos_int21h_routine: cmp ah, 9 jne short pass_int21h_printstr push dx push ax push bx mov ah, 0Fh ; Get Video Display Mode int 10h ;AH= Number of columns ;AL= Video mode ;BH= Current video page mov word ptr CS:[Program_VideoMode],ax mov byte ptr CS:[Program_VideoPage],bh pop bx push bx loc_print_$: ; Print String (with $ terminator) ; Input -> DS:DX = String Address mov BX, DX mov AL, byte ptr DS:[BX] cmp AL,'$' je short loc_int21h_9h_return ; AL = $ : end of string mov AH,0Eh mov BX, word ptr CS:[Program_CharColorAtr] ;BH= Video Page int 10h ; BIOS Service func ( ah ) = 0Eh ; Write char as TTY ;AL-char BH-page BL-color inc DX jmp short loc_print_$ loc_int21h_1h_getchar: ; Output: al, keyboard input with echo ; AL= ASCII Code ; AH= Scan Code push dx push ax xor ah,ah int 16h pop dx mov dl, al mov ax, dx push ax push bx jmp short loc_int21h_1h_echo loc_int21h_2h_printchar: ; Int 21h Function 2h Input: DL, char push dx push ax push bx loc_int21h_1h_echo: mov ah, 0Fh ; Get Video Display Mode int 10h ;AH= Number of columns ;AL= Video mode ;BH= Current video page mov word ptr CS:[Program_VideoMode],ax mov byte ptr CS:[Program_VideoPage],bh mov BL, byte ptr CS:[Program_CharColorAtr] mov AL, DL mov AH,0Eh int 10h ; BIOS Service func ( ah ) = 0Eh ; Write char as TTY ;AL-char BH-page BL-color loc_int21h_9h_return: pop bx pop ax pop dx ;sti iret loc_get_trdos_version: ; INT 21h Function AH= 30h ; Return: ; AL= Major version number ; AH= Minor version number ; BX:CX= Build Number mov ax, 10 ; TRDOS Version 1.0 xor bx, bx xor cx, cx iret loc_get_return_code: ; INT 21h Function AH=4Dh, Get Return Code ; temporary xor ax,ax iret pass_int21h_printstr: ; INT 21h Function: 0 = Terminate Program cmp ah, 0 je run_com_INT20h_handler ; INT 21h Function: 1 = Keyboard Input cmp ah, 1 je short loc_int21h_1h_getchar ; INT 21h Function: 2 = Display Output cmp ah, 2 je short loc_int21h_2h_printchar ; INT 21h Function: 4Ch = Terminate Program cmp ah, 4Ch je run_com_INT20h_handler cmp ah, 4Ah je loc_modify_alloc_mem cmp ah, 4Bh je loc_int21h_function_4Bh cmp ah, 35h je short loc_get_interrupt_vector cmp ah, 25h je short loc_set_interrupt_vector cmp ah, 2Ch je short loc_int21h_get_time cmp ah, 2Dh je loc_int21h_set_time cmp ah, 2Ah je loc_int21h_get_date cmp ah, 2Bh je loc_int21h_set_date cmp ah, 30h je short loc_get_trdos_version cmp ah, 4Dh je short loc_get_return_code cmp ah, 48h je short loc_get_return_code ; Temporary cmp ah, 49h je short loc_get_return_code ; Temporary jmp loc_invalid_function_call jmp dword ptr CS:[INT21h_Offset] loc_get_interrupt_vector: ; Get Interrupt Vector ; Input -> AL= Interrupt Number ; Output -> ES:BX= Interrupt Vector xor ah, ah mov bx, ax shl bx, 1 shl bx, 1 xor al, al push ds mov ds, ax mov es, word ptr [BX]+2 mov bx, word ptr [BX] pop ds iret loc_set_interrupt_vector: ; Set Interrupt Vector ; Input -> AL= Interrupt Number ; DS:DX= Interrupt Vector xor ah, ah push es push bx mov bx, ax shl bx, 1 shl bx, 1 xor al, al mov es, ax mov word ptr ES:[BX], dx mov word ptr ES:[BX]+2, ds pop bx pop es iret loc_int21h_get_time: ; INT 21h Function AH= 2Ch ; Output: ; CH= Hour (0-23) ; CL= Minute (0-59) ; DH= Second (0-59) ; DL= Standard Time = 0 ; DL= Daylight Savings Time = 1 mov ah, 02h int 1Ah mov al, ch and al, 0Fh mov ah, ch shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov ch, al mov al, cl and al, 0Fh mov ah, cl shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov cl, al mov al, dh and al, 0Fh mov ah, dh shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov dh, al ;sti iret loc_int21h_set_time: ; INT 21h Function AH= 2Dh ; CH= Hour (0-23) ; CL= Minute (0-59) ; DH= Second (0-59) ; DL= Standard Time = 0 ; DL= Daylight Savings Time = 1 mov al, ch aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov ch, ah mov al, cl aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov cl, ah mov al, dh aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov dh, ah push cx push dx mov ah, 02h int 1Ah mov al, dl pop dx pop cx mov dl, al mov ah, 03h int 1Ah xor ax, ax iret loc_int21h_get_date: ; INT 21h Function AH= 2Ah ; Output: ; CX= Year (1980-2099) ; DH= Month (1-12) ; DL= Day (1-31) mov ah, 04h int 1Ah mov al, ch and al, 0Fh mov ah, ch shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov ch, al mov al, cl and al, 0Fh mov ah, cl shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov cl, al mov al, ch mov ah, 100 mul ah xor ch, ch add ax, cx mov cx, ax mov al, dh and al, 0Fh mov ah, dh shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov dh, al mov al, dl and al, 0Fh mov ah, dl shr ah,1 shr ah,1 shr ah,1 shr ah,1 aad mov dl, al ;sti iret loc_int21h_set_date: ; INT 21h Function AH= 2Bh ; CX= Year (1980-2099) ; DH= Month (1-12) ; DL= Day (1-31) mov ax, cx mov cl, 100 div cl mov cl, ah mov ch, al mov al, cl aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov cl, ah mov al, ch aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov ch, ah mov al, dh aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov dh, ah mov al, dl aam shl ah, 1 shl ah, 1 shl ah, 1 shl ah, 1 or ah,al mov dl, ah mov ah, 05h int 1Ah xor ax,ax iret loc_modify_alloc_mem: ; INT 21h Function AH= 4Ah ; Modify Allocated Memory ; Input: ES -> Paragraph to be free ; BX: New allocation size in paragraphs (with 16 bytes unit) xor ax,ax iret loc_int21h_function_4Bh: ; 14/11/2009 ; INT 21h Function AH= 4Bh ; Load and Run Executable File ; INPUT ; AL= Mode (AL=0 Normal execution) ; ES:BX= Arguments ; DS:DX= Dos Dot File Name Address push ax push dx push cx push bx push si push di push ds push es push bp mov word ptr CS:[StackPointer21h], sp mov word ptr CS:[StackSegment21h], ss inc byte ptr CS:[INT21h_4Bh] push cs pop es mov si, dx ; DS:SI -> ASCIIZ Pathname string beginning address ; 14/11/2009 call proc_check_exe_filename_ext jnc short loc_int21h_load_executable_file xor ax, ax mov byte ptr [INT21h_Err_Code], al loc_int21h_4Bh_stc_iret: dec byte ptr CS:[INT21h_4Bh] mov ss, word ptr CS:[StackSegment21h] mov sp, word ptr CS:[StackPointer21h] pop bp pop es pop ds pop di pop si pop bx pop cx pop dx pop dx ;ax stc iret loc_int21h_load_executable_file: mov byte ptr CS:[EXE_ID], al mov cx, bx ; Char count of the file <= 12 mov di, offset INT21h_File_name push di rep movsb pop si push cs pop ds mov ax, 04h call proc_open_file jnc short loc_INT21h_run_loaded_executable_file mov byte ptr [INT21h_Err_Code], ah mov al, ah xor ah, ah jmp short loc_int21h_4Bh_stc_iret loc_INT21h_run_loaded_executable_file: mov word ptr [Run_Segment], ax mov word ptr [Run_Offset], 100h mov word ptr [PSP_Address], ax jmp loc_run_loaded_executable_file_INT21h_4Bh ;End Of INT 21h Function AH=4Bh Load & Run Executable File loc_invalid_function_call: ; Other Functions (invalid) pop word ptr CS:[INT_IP] pop word ptr CS:[INT_CS] pop word ptr CS:[INT_Flags] push sp push bp push ss push es push ds push cs pop ds push di push si push dx push cx push bx push ax call proc_hex mov word ptr [ValStr_AX]+2, ax pop ax mov al, ah call proc_hex mov word ptr [ValStr_AX], ax mov word ptr [ValStr_AH], ax mov al, 21h call proc_hex mov word ptr [ValStr_INT], ax mov al, byte ptr [INT_IP]+1 call proc_hex mov word ptr [ValStr_IP], ax mov al, byte ptr [INT_IP] call proc_hex mov word ptr [ValStr_IP]+2, ax mov al, byte ptr [INT_CS]+1 call proc_hex mov word ptr [ValStr_CS], ax mov al, byte ptr [INT_CS] call proc_hex mov word ptr [ValStr_CS]+2, ax mov al, byte ptr [INT_Flags]+1 call proc_hex mov word ptr [ValStr_Flags], ax mov al, byte ptr [INT_Flags] call proc_hex mov word ptr [ValStr_Flags]+2, ax pop bx mov al, bh call proc_hex mov word ptr [ValStr_BX], ax mov al, bl call proc_hex mov word ptr [ValStr_BX]+2, ax pop cx mov al, ch call proc_hex mov word ptr [ValStr_CX], ax mov al, cl call proc_hex mov word ptr [ValStr_CX]+2, ax pop dx mov al, dh call proc_hex mov word ptr [ValStr_DX], ax mov al, dl call proc_hex mov word ptr [ValStr_DX]+2, ax pop dx ; si mov al, dh call proc_hex mov word ptr [ValStr_SI], ax mov al, dl call proc_hex mov word ptr [ValStr_SI]+2, ax pop dx ; di mov al, dh call proc_hex mov word ptr [ValStr_DI], ax mov al, dl call proc_hex mov word ptr [ValStr_DI]+2, ax pop dx ; ds mov al, dh call proc_hex mov word ptr [ValStr_DS], ax mov al, dl call proc_hex mov word ptr [ValStr_DS]+2, ax pop dx ; es mov al, dh call proc_hex mov word ptr [ValStr_ES], ax mov al, dl call proc_hex mov word ptr [ValStr_ES]+2, ax pop dx ; ss mov al, dh call proc_hex mov word ptr [ValStr_SS], ax mov al, dl call proc_hex mov word ptr [ValStr_SS]+2, ax pop dx ; bp mov al, dh call proc_hex mov word ptr [ValStr_BP], ax mov al, dl call proc_hex mov word ptr [ValStr_BP]+2, ax pop dx ; sp mov al, dh call proc_hex mov word ptr [ValStr_SP], ax mov al, dl call proc_hex mov word ptr [ValStr_SP]+2, ax mov ah, 0 mov al, 3 ; 80*25 text mode, color with CGA card int 10h mov si, offset msg_invalid_function_call call proc_printmsg mov si, offset msg_function_registers call proc_printmsg jmp run_com_int20h_handler_ctrlbrk INT21h_File_Name: db 13 dup(0) INT21h_Err_Code: db 0 INT_IP: dw 0 INT_CS: dw 0 INT_FLAGS: dw 0 msg_invalid_function_call: db 7 db 0Dh, 0Ah, 0Dh, 0Ah db "*** Invalid function call for TRDOS ! ***" db 0Dh, 0Ah, 0 msg_function_registers: db 0Dh, 0Ah db "INT " ValStr_INT: dw 3030h db "h" db " " db "Function AH = " ValStr_AH: dw 3030h db "h" db 0Dh, 0Ah, 0Dh,0Ah db "Registers: ", 0Dh, 0Ah db "AX = " ValStr_AX: dd 30303030h db "h " db "BX = " ValStr_BX: dd 30303030h db "h " db "CX = " ValStr_CX: dd 30303030h db "h " db "DX = " ValStr_DX: dd 30303030h db "h", 0Dh, 0Ah db "CS = " ValStr_CS: dd 30303030h db "h " db "IP = " ValStr_IP: dd 30303030h db "h " db "Flags = " ValStr_Flags: dd 30303030h db "h", 0Dh, 0Ah db "DS = " ValStr_DS: dd 30303030h db "h " db "ES = " ValStr_ES: dd 30303030h db "h " db "SI = " ValStr_SI: dd 30303030h db "h " db "DI = " ValStr_DI: dd 30303030h db "h", 0Dh, 0Ah db "SS = " ValStr_SS: dd 30303030h db "h " db "SP = " ValStr_SP: dd 30303030h db "h " db "BP = " ValStr_BP: dd 30303030h db "h", 0Dh, 0Ah, 0Dh, 0Ah, 0 ; End Of TRDOS Function Calls