微机原理实验8255并行口实验PA输入、PB输出讲课教案

微机原理实验8255并行口实验P A输入、P B输出8255A并行口实验PA输入、PB输出利用LED等显示程序LCD EQU 07FE0HLCDWI EQU LCD+0 ;写命令LCDWD EQU LCD+1 ;写数据LCDRS EQU LCD+2 ;读状态LCDRD EQU LCD+3 ;读数据PA EQU 0FFD8HPB EQU 0FFD9HPC EQU 0FFDAHPCTL EQU 0FFDBHcode segmentassume cs:codelin db 0col db 0num db 0dis_num db 0temp0 db 0temp1 db 0count db 0org 1000hstart: MOV DX,PCTLMOV AL,90HOUT DX,ALcall init_lcdmov al,3call delay2mov count,0mov bx,offset tab0mov lin,0mov col,0mov num,16call dis_englishGOON: MOV DX,PAIN AL,DXTEST AL,01HJE GOON1TEST AL,02HJE GOON2TEST AL,04HJZ GOON3TEST AL,08HJE GOON4TEST AL,10HJE GOON5TEST AL,20HJE GOON6TEST AL,40HJE GOON7TEST AL,80HJZ GOON8JMP GOON9GOON1: JMP KEY1GOON2: JMP KEY2GOON3: JMP KEY3GOON4: JMP KEY4GOON5: JMP KEY5GOON6: JMP KEY6GOON7: JMP KEY7GOON8: JMP KEY8GOON9: mov bx,offset tab9 mov lin,1mov col,0mov num,16call dis_englishMOV DX,PBMOV AL,0FFHOUT DX,ALJMP GOONKEY1: MOV DX,PBMOV AL,0FEHOUT DX,ALmov bx,offset tab1mov lin,1mov col,0mov num,16call dis_englishJMP GOONKEY2: MOV DX,PBMOV AL,0FDHOUT DX,ALmov bx,offset tab2 mov lin,1mov col,0mov num,16call dis_englishJMP GOONKEY3: MOV DX,PBMOV AL,0FBHOUT DX,ALmov bx,offset tab3 mov lin,1mov col,0mov num,16call dis_englishJMP GOONKEY4: MOV DX,PBMOV AL,0F7HOUT DX,ALmov bx,offset tab4 mov lin,1mov col,0mov num,16call dis_englishJMP GOONKEY5: MOV DX,PBMOV AL,0EFHOUT DX,ALmov bx,offset tab5 mov lin,1mov col,0mov num,16call dis_englishJMP GOONKEY6: MOV DX,PBMOV AL,0DFHOUT DX,ALmov bx,offset tab6 mov lin,1mov col,0mov num,16call dis_englishJMP GOONKEY7: MOV DX,PBMOV AL,0BFHOUT DX,ALmov bx,offset tab7mov lin,1mov col,0mov num,16call dis_englishJMP GOONKEY8: MOV DX,PBMOV AL,07FHOUT DX,ALmov bx,offset tab8mov lin,1mov col,0mov num,16call dis_englishJMP GOONdis_number procpush axmov al,lin ;以下18条为根据行、列值定位显示英文起始坐标 cmp al,0jnz nu0mov al,80hjmp nu1nu0: cmp al,1jnz nuretmov al,0C0hnu1: add al,colcall send_commov ah,0 ;以下10条为把3位十进制数的个位、十位、百位分离 mov al,dis_nummov bl,10div blmov temp0,ahmov ah,0mov bl,10div blmov temp1,ahadd al,30h ;转为ASC码call send_data ;百位送LCD显示mov al,temp1add al,30h ;转为ASC码call send_data ;十位送LCD显示mov al,temp0add al,30h ;转为ASC码call send_data ;个位送LCD显示pop axnuret: retdis_number endp;--------------------------;在指定的行、列显示英文。

每行可显示16个英文字符，共4行;参数：行lin(0~1)；列col(0~16) 英文个数num(0~15); 表地址bx;--------------------------dis_english procpush axmov al,lin ;以下18条为根据行、列值定位显示英文起始坐标 cmp al,0jnz ch0mov al,80hjmp ch1ch0: cmp al,1jnz chretmov al,0C0hch1: add al,colcall send_commov ah,numch2: mov al,[bx]inc bxcall send_datadec ahjnz ch2pop axchret: retdis_english endp;--------------------------;清LCD屏;--------------------------close_lcd procpush axmov al, 01h ;清除命令call send_compop axretclose_lcd endp;--------------------------;初始化LCD;col 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15;lin0： 80 81 82 83 84 85 86 87 88 89 8a 8b 8c 8d 8e 8f;lin1： C0 C1 C2 C3 C4 C5 C6 C7 C8 C9 Ca Cb Cc Cd Ce Cf ;--------------------------init_lcd procmov dx,LCDWI ;启动LCDmov al,30hout dx,al ;第1次启动LCDcall delay ;延时mov al,30hout dx,al ;第2次启动LCDcall delay ;延时mov al,30hout dx,al ;第3次启动LCDcall delay ;延时mov al,38h ;设置工作模式：out dx,al ;汇流、2行、5*7点阵call delay ;延时mov al,08h ;关显示out dx,alcall delay ;延时mov al,01h ;LCD清屏out dx,alcall delay ;延时mov al,0eh ;开显示、光标不闪烁out dx,alcall delay ;延时call chkbusy ;检测LCD状态lcd_p: mov al,06h ;光标右移且地址加1call send_commov al,02h ;光标归位call send_comcall delay ;延时retinit_lcd endp;-----------------------;读LCD忙闲状态;-----------------------chkbusy procpush dxpush axmov dx,LCDRSrechk: in al,dxmov cl,aljc rechkpop axpop dxretchkbusy endp;----------------------;写LCD命命;---------------------- send_com proccall chkbusypush dxmov dx,LCDWI out dx,alpop dxretsend_com endp;----------------------- ;写LCD数据;----------------------- send_data proccall chkbusypush dxmov dx,LCDWD out dx,alpop dxretsend_data endp;----------------------- ;延时子程序;----------------------- delay procpush cxmov cx,1000hloop $pop cxretdelay endp;-------------------------- ;延时子程序;-------------------------- delay1 procpush cxmov cx, 0080hpop cxretdelay1 endp;--------------------------;延时子程序;AL是延时参数;--------------------------delay2 procpush axpush cxmov ah, 0mov cx, axdloop: push cxmov cx, 65535loop $pop cxloop dlooppop cxpop axretdelay2 endpTAB0 DB "KEY "TAB1 DB "KEY1 open " TAB2 DB "KEY2 open " TAB3 DB "KEY3 open " TAB4 DB "KEY4 open " TAB5 DB "KEY5 open " TAB6 DB "KEY6 open " TAB7 DB "KEY7 open " TAB8 DB "KEY8 open " TAB9 DB "ALLKEY close " code endsend start。