; **************************************************************************** ; MFP.ASM (by Erdogan Tan) ; ; TRDOS Kernel Test program for ; INT 21h Function 42h, Move File Pointer, ; 09/04/2011 ; ; **************************************************************************** PSP_CommandTail equ 80h .8086 SINGLIXBOOT SEGMENT PUBLIC 'CODE' assume cs:SINGLIXBOOT,ds:SINGLIXBOOT,es:SINGLIXBOOT,ss:SINGLIXBOOT org 100h START_CODE: proc_start proc near xor bh, bh mov si, PSP_CommandTail mov bl, byte ptr [SI] or bl, bl jnz short loc_open_file_int21h ; jump if not zero int 20h loc_open_file_int21h: inc si mov byte ptr [SI][BX], bh ; 0 loc_open_file_int21h_next: inc si mov al, byte ptr [SI] cmp al, 20h ; is it SPACE ? ja short loc_open_file_int21h_fcall dec bl jnz short loc_open_file_int21h_next int 20h loc_open_file_int21h_fcall: call proc_open_file jc short loc_open_file_int21h_err mov word ptr [File_Handle], ax jmp short loc_open_file_int21h_ok loc_open_file_int21h_err: push ax mov al, ah call proc_hex mov word ptr [Error_Number], ax pop ax call proc_hex mov word ptr [Error_Number]+2, ax mov si, offset Error_Number_Str call PROC_PRINTMSG int 20h loc_open_file_int21h_ok: mov al, 0 mov bx, ax add bx, 30h mov byte ptr [MFP_Mode], bl mov cx, 0FFFFh mov dx, 0FFFFh mov bx, word ptr [File_Handle] call proc_move_file_pointer push ax mov ax, dx call proc_hex_double mov word ptr [File_Pointer_hw], dx mov word ptr [File_Pointer_hw]+2, ax pop ax call proc_hex_double mov word ptr [File_Pointer_lw], dx mov word ptr [File_Pointer_lw]+2, ax mov si, offset File_Ptr_Str call PROC_PRINTMSG mov al, 1 mov bx, ax add bx, 30h mov byte ptr [MFP_Mode], bl mov cx, 0FFFFh mov dx, 0FFFFh mov bx, word ptr [File_Handle] call proc_move_file_pointer push ax mov ax, dx call proc_hex_double mov word ptr [File_Pointer_hw], dx mov word ptr [File_Pointer_hw]+2, ax pop ax call proc_hex_double mov word ptr [File_Pointer_lw], dx mov word ptr [File_Pointer_lw]+2, ax mov si, offset File_Ptr_Str call PROC_PRINTMSG mov al, 2 mov bx, ax add bx, 30h mov byte ptr [MFP_Mode], bl mov cx, 0FFFFh mov dx, 0FFFFh mov bx, word ptr [File_Handle] call proc_move_file_pointer push ax mov ax, dx call proc_hex_double mov word ptr [File_Pointer_hw], dx mov word ptr [File_Pointer_hw]+2, ax pop ax call proc_hex_double mov word ptr [File_Pointer_lw], dx mov word ptr [File_Pointer_lw]+2, ax mov si, offset File_Ptr_Str call PROC_PRINTMSG mov al, 0 mov bx, ax add bx, 30h mov byte ptr [MFP_Mode], bl mov cx, 0 mov dx, 1 mov bx, word ptr [File_Handle] call proc_move_file_pointer push ax mov ax, dx call proc_hex_double mov word ptr [File_Pointer_hw], dx mov word ptr [File_Pointer_hw]+2, ax pop ax call proc_hex_double mov word ptr [File_Pointer_lw], dx mov word ptr [File_Pointer_lw]+2, ax mov si, offset File_Ptr_Str call PROC_PRINTMSG mov al, 1 mov bx, ax add bx, 30h mov byte ptr [MFP_Mode], bl mov cx, 0FFFFh mov dx, 0FFFEh mov bx, word ptr [File_Handle] call proc_move_file_pointer push ax mov ax, dx call proc_hex_double mov word ptr [File_Pointer_hw], dx mov word ptr [File_Pointer_hw]+2, ax pop ax call proc_hex_double mov word ptr [File_Pointer_lw], dx mov word ptr [File_Pointer_lw]+2, ax mov si, offset File_Ptr_Str call PROC_PRINTMSG mov al, 2 mov bx, ax add bx, 30h mov byte ptr [MFP_Mode], bl mov cx, 0FFh mov dx, 0FFFFh mov bx, word ptr [File_Handle] call proc_move_file_pointer push ax mov ax, dx call proc_hex_double mov word ptr [File_Pointer_hw], dx mov word ptr [File_Pointer_hw]+2, ax pop ax call proc_hex_double mov word ptr [File_Pointer_lw], dx mov word ptr [File_Pointer_lw]+2, ax mov si, offset File_Ptr_Str call PROC_PRINTMSG loc_close_file_int21h: mov bx, word ptr [File_Handle] mov ah, 3Eh ; MS DOS Function = Close File int 21h ;jc short loc_open_file_int21h_err int 20h proc_start endp PROC_PRINTMSG proc near LOC_PRINTMSG_LOOP: lodsb ; Load byte at DS:SI to AL and AL,AL jz short LOC_PRINTMSG_OK mov AH,0Eh mov BX,07h int 10h ; BIOS Service func ( ah ) = 0Eh ; Write char as TTY ;AL-char BH-page BL-color jmp short LOC_PRINTMSG_LOOP LOC_PRINTMSG_OK: retn PROC_PRINTMSG endp proc_open_file proc near mov ah,0Eh mov bx,07h mov al,0Dh int 10h mov al,0Ah int 10h loc_open_file: mov dx, si mov ah, 3Dh ; MS DOS Function = Open File mov al, 0 int 21h retn proc_open_file endp ;''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''; ; From binary (byte) to hexadecimal (character) converter ; ; ; ; input -> AL = byte (binary number) to be converted ; ; output -> AH = First character of hexadecimal number ; ; output -> AL = Second character of hexadecimal number ; ; ; ; (c) Erdogan TAN 1998 - 1999 ; ;............................................................; ; 1998 proc_hex proc near db 0D4h,10h ; Undocumented inst. AAM ; AH = AL / 10h ; AL = AL MOD 10h or AX,'00' ; Make it ZERO (ASCII) based xchg AH,AL ; 1999 cmp AL,'9' jna pass_cc_al add AL,7 pass_cc_al: cmp AH,'9' jna pass_cc_ah add AH,7 pass_cc_ah: ; 1998 retn proc_hex endp ;''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''; ; From binary (word) to hexadecimal (character) converter ; ; ; ; input -> AX = word (binary number) to be converted ; ; output -> DX = First 2 characters of hexadecimal number ; ; output -> AX = Last 2 characters of hexadecimal number ; ; ; ; (c) Erdogan Tan [ 28/1/2002 ] ; ;............................................................; proc_hex_double proc near push cx xor dx, dx mov cx, 10h div cx ; Q in AX, R in DX (DL) xchg dh, dl ; DH= 0, R in DL <- CX= 10h push dx ; R in DH, DL= 0 xor dh, dh div cx push dx ; R in DL, DH= 0, AX <= FFh div cl ; AX <= 0Fh ; R in AH, Q in AL, AL (Q) is 0 push ax pop dx ; High Word Characters is in DX pop cx ; R in CL pop ax ; R in AH, AL = 0 or al, cl or DX,'00' cmp DL,'9' jna short pass_dcc_dl add DL,7 pass_dcc_dl: cmp DH,'9' jna short pass_dcc_dh add DH,7 pass_dcc_dh: or AX, '00' cmp AL,'9' jna short pass_dcc_al add AL,7 pass_dcc_al: cmp AH,'9' jna short pass_dcc_ah add AH,7 pass_dcc_ah: pop cx retn proc_hex_double endp proc_move_file_pointer proc near mov ah, 42h ;mov bx, word ptr [File_Handle] int 21h retn proc_move_file_pointer endp ;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - ; data ;- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - File_Ptr_Str: db 'File Pointer ' db '(' MFP_Mode: db 0 db ') = ' File_Pointer_hw: dd 30303030h File_Pointer_lw: dd 30303030h db 'h ' db 0Dh, 0Ah, 0 Error_Number_Str: db "Error Number: " Error_Number: dd 0 db "h" db 0Dh, 0Ah, 0 File_Read_Error_Str: db 'File Read Error !' Next_Line: db 0Dh, 0Ah, 0 Show_Byte_Count: dw 0 Page_Number: dw 0 File_Handle: dw 0 File_Buffer: db 1 dup (0) FBuffer_Size equ $ - offset File_Buffer db 0 SINGLIXBOOT ends end START_CODE