微机实训报告

mov dx,0ff23h ;读取键行值 in al,dx not al nop nop

and al,0fh ;判有键否？ jnz key2

inc bl ; loop key1 ;

jmp nkey ;key2: test al,01h ; je key3 mov al,00h

jmp key6

key3: test al,02h je key4 mov al,08h

jmp key6

key4: test al,04h je key5 mov al,10h

jmp key6

key5: test al,08h je nkey

mov al,18h

key6: add al,bl

无键，扫描次数加1 不满8列继续 转无键处理

计算键值

cmp al,10h jnc fkey mov bl,al mov bh,0h

lea si,data2

mov al,cs:[bx+si] ;键值存在AL中 ret

nkey: ;mov al,20h ;无键值为20H mov al,byte ptr ds:[077dh] fkey: ret

data2: db 07h,04h,08h,05h,09h,06h,0ah,0bh ;键值表（数字键）

DB 01h,00h,02h,0fh,03h,0eh,0ch,0dh

MYISR PROC NEAR ;中断处理程序MYISR PUSH AX

MOV AL,DIR CMP AL,0 JZ DOWN CMP AL,2 JZ UP jmp redikey DOWN:

MOV AL,NOW_FLOOR DEC AL

MOV NOW_FLOOR,AL

MOV BX,OFFSET DTABLE

AND AX,00FFH ADD BX,AX MOV AL,[BX]

MOV DX,MY8255_B

OUT DX,AL JMP BIJIAO

UP:

MOV BX,OFFSET DTABLE

AND AX,00FFH ADD BX,AX MOV AL,[BX] MOV AL,NOW_FLOOR INC AL

MOV NOW_FLOOR,AL

MOV DX,MY8255_B BIJIAO:

MOV AL,NOW_FLOOR MOV AH,TARGET_FLOOR CMP AH,AL JZ GUANBI jmp redikey GUANBI:

OUT DX,AL

MOV DX,MY8255_MODE

MOV AL,00001110B ;PC7=0 OUT DX,AL MOV DIR,1H

MOV AL,0

MOV DX,1300H ;标楼层

OUT DX,AL

MOV F_FLOOR,1 ; MOV DX,MY8254_MODE ; MOV AL,36H ; OUT DX,AL

MOV SI,OFFSET FREQ_LIST ; MOV DI,OFFSET TIME_LIST ; MOV DX,0FH ;1.0416667M = 0FE502H MOV AX,0E502H

DIV WORD PTR [SI] ;/ 输出频率

MOV DX,MY8254_COUNT0

OUT DX,AL ; MOV AL,AH OUT DX,AL

MOV DL,[DI] ;用IO-32输出控制8个LED，显示目置1，恢复按键有效 初始化8254工作方式 定时器0、方式3 装入频率表起始地址 装入时间表起始地址

输入时钟为1.0416667MHz，取出频率值计算计数初值，0F4240H 装入计数初值 取出演奏相对时间，调用延时子程