; (C)opyright Erdogan Tan - 30 April 2000 (4) ; ; INT1CS.ASM (Standalone version of INT1C.ASM.) ; ; Handles INT 1Ch for showing current date and time. ; This is INT 1Ch handling type version of CDT.ASM or DATETIME.ASM. ; ; Program uses INT 15h Function 85h, SysReq key handler ; for checking stop/exit request. (Alt+SysRq keystrokes.) ; ; After performing SysReq procedure, program restores ; original INT 1Ch and INT 15h vectors. ; ; ROM-BIOS functions are derived from American Megatrend Inc.'s ; AMIBIOS Programming Guide (1993). PAGE 60,132 ;ÄÄÄÄÄÄÄÄÄÄ CODE_SEG_1 ÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄ CODE_SEG_1 segment para public assume CS:CODE_SEG_1, DS:CODE_SEG_1, SS:CODE_SEG_1, ES:CODE_SEG_1 org 100h ;±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±± ;± ;± ENTRY POINT ;± ;±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±± ;±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±± ;± ;± PROCEDURE proc_start ;± ;±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±± proc_start proc near start: ; N-Ref=0 jmp load Magic_Word: dw 0 var_INT15h_off: dw 0 var_INT15h_seg: dw 0 var_INT1Ch_off: dw 0 var_INT1Ch_seg: dw 0 proc_start endp ;±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±± ;± ;± PROCEDURE proc_handler ;± ;±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±± proc_handler proc near INT1Ch_handler: pushf call dword ptr CS:var_INT1Ch_off push ax push bx push cx push dx push si push di push ds push es push cs pop ds mov ah, 03h mov bx, 07h int 10h ; Return Cursor Position mov word ptr [CursorPos], dx mov ah, 04h int 1Ah mov al, ch call proc_hex mov word ptr [Century], ax mov al, cl call proc_hex mov word ptr [Year], ax mov al, dh call proc_hex mov word ptr [Month], ax mov al, dl call proc_hex mov word ptr [Day], ax mov ah, 02h int 1Ah mov al, ch call proc_hex mov word ptr [Hour], ax mov al, cl call proc_hex mov word ptr [Minute], ax mov al, dh call proc_hex mov word ptr [Second], ax mov dx, 30h mov ah, 02h mov bx, 07h int 10h ; Set Cursor Position mov si, offset Msg_Date call proc_printmsg return_from_INT1Ch: mov dx, word ptr [CursorPos] mov ah, 02h mov bx, 07h int 10h ; Set Cursor Position pop es pop ds pop di pop si pop dx pop cx pop bx pop ax IRET SYSREQ_handler: push ax pushf call dword ptr CS:var_INT15h_off pop ax push ax push si push di push ds push es push cs pop ds cmp ah, 85h jnz short return_from_INT15h xor ax, ax mov es, ax mov di, 70h mov si, offset var_INT1Ch_off movsw movsw mov di, 54h mov si, offset var_INT15h_off movsw movsw Return_from_INT15h: pop es pop ds pop di pop si pop ax IRET proc_handler endp proc_printmsg proc near loc_print: lodsb ; Load byte at DS:SI to AL and AL,AL je short end_of_print ; If AL = 00h then return 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_print end_of_print: retn proc_printmsg 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 Msg_Copyrights: db 0Dh, 0Ah db "INT 1Ah FUNCTION 04h DATE AND 02h TIME OUTPUTS" db 0Dh, 0Ah db "via INT 1Ch Periodic Timer Interrupt" db 0Dh, 0Ah db "and INT 15h FUNCTION 85h SysReq Key Handler" db 0Dh, 0Ah db 0Dh, 0Ah db "(c) Erdogan Tan [ 2000 ]" db 0Dh, 0Ah db 0Dh, 0Ah db "Press Alt+SysRq keys when you want to exit." db 0Dh, 0Ah db 0Dh, 0Ah, 0 Msg_Date: db "Date: " Day: db '0' db '0' db '/' Month: db '0' db '0' db '/' Century: db '0' db '0' Year: db '0' db '0' db 20h db 20h db 'Time: ' Hour: db '0' db '0' db ':' Minute: db '0' db '0' db ':' Second: db '0' db '0' db 0Dh, 0Ah db 0Dh, 0Ah db 0 CursorTyp: dw 0 CursorPos: dw 0 ;±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±± ;± ;± PROCEDURE proc_load ;± ;±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±±± proc_load proc near load: xor BX,BX mov ES,BX mov SI,70h mov AX, offset INT1Ch_handler mov DX, Word ptr ES:[SI] cmp AX,DX jnz short pass_INT1Ch_magicword_ctrl mov BX, AX sub BX, 10 cmp word ptr [BX], 417 jz short loc_return pass_INT1Ch_magicword_ctrl: mov word ptr ES:[SI],AX mov Word Ptr [var_INT1Ch_off],DX mov DX, Word ptr ES:[SI]+2 mov Word Ptr [var_INT1Ch_seg],DX mov DX,DS mov word ptr ES:[SI]+2,DX mov word ptr [Magic_Word], 417 mov SI, 54h mov AX, word ptr ES:[SI] mov word ptr [var_INT15h_off],AX mov AX, word ptr ES:[SI]+2 mov word ptr [var_INT15h_seg],AX mov AX, offset SYSREQ_handler mov word ptr ES:[SI],AX mov word ptr ES:[SI]+2,DX mov si, offset Msg_Copyrights call proc_printmsg loc_return: int 20h proc_load endp CODE_SEG_1 ends end start