【正文】 mov eax,0a0f0000h out dx,eax ；判斷默認開始鍵 ss2: call setsaomiao call keyup mov al,key cmp al,0ffh jz ss1 cmp al,0ch C 鍵 默認 價格計價 jnz ss3 mov al,fee1s fee1s 保存 默認值或上次設定值 mov fee1,al mov al,fee2s mov fee2,al mov al,danjias mov danjia,al call xianfee call zhuan jmp goon1 計程車 計價器設計報告 21 ss3: mov dx,208h 第 3片 8255 顯示 橫桿 mov eax,0a050000h out dx,eax mov al,0bfh mov dx,202h out dx,al mov dx,206h out dx,al ；設置起始價百位 call setsaomiao 等待 按鍵 mov al,key 將 Key 賦值到 fee2 的 高四位 lea si,mess1 mov al,key and ah,00h add si,ax mov al,[si] mov dx,200h out dx,al call keyup mov al,key shl al,4 and al,0f0h mov fee2,al ；設置起始價十位 call setsaomiao mov al,key 將 Key 賦值到 fee2 的低 四位 and al,0fh or al,fee2 mov fee2,al mov fee2s,al mov al,key 計程車 計價器設計報告 22 lea bx,mess1 xlat mov dx,204h out dx,al call keyup ；設置起始價的 個 位 call setsaomiao mov al,key 將 Key 賦值 到 fee1 的 高 四位 shl al,4 and al,0f0h mov fee1,al mov al,key lea bx,mess2 xlat mov dx,201h out dx,al call keyup ；設置起始價小數(shù) 位 call setsaomiao mov al,key and al,0fh or al,fee1 mov fee1,al mov fee1s,al mov al,key lea bx,mess1 xlat mov dx,205h out dx,al call keyup 計程車 計價器設計報告 23 ；等到確認鍵 lp1: call setsaomiao mov al,key cmp al,0ah jz goon cmp al,0dh D鍵 消除 鍵 jnz gojp mov al,00h mov fee1,al mov fee2,al call xianfee call keyup jmp ss3 ；清除 gojp: jmp lp1 goon: call keyup ；設置單價 ss4: call setsaomiao mov al,key 設置 單價 個位 shl al,4 mov danjia,al mov al,key lea bx,mess2 xlat mov dx,203h out dx,al call keyup call setsaomiao mov al,key 設置單價小數(shù)位 or al,danjia 計程車 計價器設計報告 24 mov danjia,al mov danjias,al mov al,key lea bx,mess1 xlat mov dx,207h out dx,al call keyup 等待 確認 lp3: call zhuan call setsaomiao call keyup mov al,key cmp al,0ah Jz goon1 cmp al,0dh jnz gojp1 mov al,0c0h mov dx,203h out dx,al mov dx,207h out dx,al call keyup jmp ss4 gojp1: jmp lp3 。 計算每角錢行駛距離 zhuan proc near mov bl,00h mov cl,01h mov al,danjia mov danjia1,al zhuanag: mov al,danjia1 add al,danjia daa mov danjia1,al jnc zhuan1 inc bl zhuan1: mov al,cl 計程車 計價器設計報告 31 add al,01h daa mov cl,al cmp bl,0ah jnz zhuanag mov jiaogl,cl ret zhuan endp 。 ；鍵盤掃描 jpsaomiao proc push ax push bx push cx mov bl,0f7h nxtcol: mov al,bl mov dx,308h out dx,al mov dx,300h in al,dx and al,0fh cmp al,0fh jnz fndkey ror bl,1 jc nxtcol mov al,0ffh 計程車 計價器設計報告 33 mov key,al jmp kscanover fndkey:shl bl,4 or bl,al call delay mov al,00h lea si,anjiantz lpjian: mov cl,[si] cmp bl,cl jz transkey inc al inc si jmp lpjian transkey:mov key,al kscanover: pop cx pop bx pop ax ret jpsaomiao endp 。 ；顯示費用 xianfee proc near push ax mov dx,20ch mov eax,80808080h out dx,eax mov dx,200h mov eax,0c0c0c0c0h out dx,eax mov dx,204h mov eax,0c0c0c0c0h out dx,eax mov dx,208h mov eax,0a0f0000h out dx,eax mov al,fee2 and al,0f0h 計程車 計價器設計報告 35 shr al,4 and al,0fh lea bx,mess1 xlat mov dx,200h out dx,al mov al,fee2 and al,0fh xlat mov dx,204h out dx,al mov al,fee1 and al,0fh xlat mov dx,205h out dx,al lea bx,mess2 mov al,fee1 and al,0f0h shr al,4 xlat mov dx,201h out dx,al lea bx,mess1 mov al,danjia and al,0fh xlat mov dx,207h out dx,al lea bx,mess2 mov al,danjia 計程車 計價器設計報告 36 and al,0f0h shr al,4 xlat mov dx,203h out dx,al pop ax ret xianfee endp 。延時程序 delay proc near push cx mov cx,8fh dlp : nop loop dlp