;name: ELECTRONIC CLOCK
                         ;design by zengqingyu class1 and moxiaolei class3
data  segment

mess1   db  '                                   \\\|///                                              ',0ah,0dh
        db  '                                \\　.-.-　//                                            ',0ah,0dh
        db  '                                 (　.@.@　)                                             ',0ah,0dh
        db  '                +-----------oOOo-----(_)-----oOOo-------------+                         ',0ah,0dh
        db  '                +               ASM   ASSIGNMENT              +                         ',0ah,0dh
        db  '                +               ELECTRONIC CLOCK              +                         ',0ah,0dh
        db  '                +             Design by Kevin & Ray           +                         ',0ah,0dh
        db  '                +                                 version:1.0 +                         ',0ah,0dh
        db  '                +                                             +                         ',0ah,0dh
        db  '                +                                             +                         ',0ah,0dh
        db  '                +                    Press ESC button to quit +                         ',0ah,0dh
        db  '                +-------------------------Oooo----------------+                         ','$'
mess2   db  'The time is now:',0ah,0dh,'$'
t_buff  db 20            ;在數(shù)據(jù)段開辟一時間顯示緩沖區(qū)
data  ends

stack segment
      db 100 dup(?)
stack ends

code  segment
      assume cs:code,ss:stack,ds:data
main:
      call clear         ;調(diào)用清屏子程序

display: ;----------------------------時間顯示部分--------------
      mov ax,seg data
      mov ds,ax
      mov bx,offset t_buff      ;送t_buff的偏移地址到BX
      mov ah,2ch                 ;調(diào)用DOS時間調(diào)用功能,功能號:2cH,小時,分鐘,秒數(shù)分別保存在CH,CL,DH中
      int 21h
      mov al,ch                ;小時數(shù)設定
      mov ah,0
      call bctd                 ;調(diào)用進制轉(zhuǎn)換子程序
      push ax
      and al,0f0h                ;選取al高四位
      mov cl,4                   ;設置右循環(huán)的次數(shù)
      rol al,cl                   ;右循環(huán)
      or al,30h                    ;加30h得到ACSII碼
      mov [bx],al                 ;將得到的結(jié)果送到t_buff緩沖區(qū)
      inc bx                       ;BX自加1,指針指向下一個緩沖區(qū)的下一個地址
        
        
      pop ax
      and al,0fh                 ;選取低四位,道理同上
      or al,30h
      mov [bx],al                 ;將轉(zhuǎn)換后的低四位值送入緩沖區(qū)的第二個地址
      inc bx
  ;----------------------------------------------------------
      mov al,':' ;顯示分號
      mov [bx],al
      inc bx
   ;-------------------------------------------------------
      mov ah,2ch
      int 21h
        
      mov al,cl                ;分鐘數(shù)設定
      mov ah,0
      call bctd
      push ax
      and al,0f0h
      mov cl,4
      rol al,cl
      or al,30h

      mov [bx],al
      inc bx
      pop ax
      and al,0fh
      or al,30h
      mov [bx],al
      inc bx
  ;-------------------------------------------------------------------------
      mov al,':'                    ;顯示;號
      mov [bx],al
      inc bx
  ;-------------------------------------------------------------------------
        
      mov ah,2ch                    ;秒設定
      int 21h
      mov al,dh
      mov ah,0
      call bctd
      push ax
      and al,0f0h
      mov cl,4
      rol al,cl
      or al,30h

      mov [bx],al
      inc bx
      pop ax
      and al,0fh
      or al,30h
      mov [bx],al
      inc bx
  ;----------------------------------------------------------------------
      mov al,'$'      ;將字符串的結(jié)束位送至顯示緩沖區(qū)的最后一位
      mov [bx],al
   ;------------------------------------------------------------------------
      push  bx      ;置光標位置 ,AH=2,BH=0,DH跟DL分別為行號與列號,并入棧保護BX
      mov ah,2
      mov bh,0
      mov dh,17
      mov dl,41
      int 10h
      pop bx
      lea dx,t_buff  ;送t_buff偏移地址到DX,并調(diào)用DOS顯示功能,功能號為9
      mov ah,9
      int 21h

      push  bx      ;置光標位置
      mov ah,2
      mov bh,0
      mov dh,0
      mov dl,0
      int 10h
      pop bx
      lea dx,mess1
      mov ah,9
      int 21h
        
      push  bx      ;置光標位置
      mov ah,2
      mov bh,0
      mov dh,17
      mov dl,21
      int 10h
      pop bx

      lea dx,mess2
      mov ah,9
      int 21h
        
 ;-----------------------------
      call delay1
      mov ah,1              ;按任意鍵結(jié)束,調(diào)用鍵盤I/O中斷功能號1,獲取鍵值到AL
      int 16h
      cmp al,1bh
      jz   quit          ;是ESC鍵的話就跳轉(zhuǎn)
      jmp   display
      
quit:
     mov ah,4ch
     int 21h
     ret
      

;-------------------------------
bctd proc near;二進制轉(zhuǎn)BCD碼子程序
;AX輸入?yún)?shù)
;AX輸出參數(shù),存放調(diào)整過的BCD碼
;
      mov   dx,ax
      mov   ax,0
      mov   cx,16        ;設循環(huán)次數(shù)
bctd1:
      clc               ;清進位標志C
      rcl   dx,1        ;通過進位的循環(huán)右移
      adc   al,al       ;帶進位加法
      daa               ;加法的十進制調(diào)整
      xchg  al,ah       ;交換高,低八位
      adc   al,al
      daa
      xchg  al,ah
      loop  bctd1        ;循環(huán),次數(shù)保存在CX里
      ret
bctd   endp
;-------------------------------------------
clear proc near
      push  ax     ;入棧保護現(xiàn)場
      push  bx
      push  cx
      push  dx
      mov ax,0600h;ah=06(滾動)al=00(全屏空白)
      mov bh,3fh  ;背景顏色(3),白色前景(f)
      sub cx,cx
      mov dx,5f5fh
      int 10h
      pop dx        ;出?；謴同F(xiàn)場
      pop cx
      pop bx
      pop ax
      ret
clear endp



;-----------------------------------------
delay1 PROC ;精確延遲時間子程序

	MOV DX,04ffh    ;循環(huán)次數(shù)
up:	XOR CX,CX
a:	NOP
	LOOP a
	DEC DX
	JNZ up
	RET
delay1 ENDP
;----------------------------
code  ends
      end main