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;-------------------------------------------------------------------------------------------
;长按学习板上的K4，会在串口上打印出 key0 event happen!
;-------------------------------------------------------------------------------------------
;2017.9.15
;用nasm重新写原来的代码
;推出配套的《在做中学微机原理》课程，与所销售的硬件相配套
;从第一行程序开教，一步一步带你走入神秘的8086世界。
;
;例程001
;ex1.asm =example_1
;8088启动,点亮系统板上的LED
;重点在于正确使用程序编辑环境，nasm汇编方法，EEprom的烧写方法
;
;ex001----用下载到RAM中的程序，点亮系统板上的LED
;8088.asm是汇编源程序
;8088.bin是编译生成的可下载执行的最终代码
;
;编译很简单，双击make即可自动完成
;
;Notepad++是我计算机上Notepad++的快捷方式
;---------------------------------------------------------------------------------------------
led_port equ 800h
_8255_port3 equ 203h
_8255_porta equ 200h
_8255_portb equ 201h
_8255_portc equ 202h
;---------------------------------------------------------------------------------------------
org 2000h ;程序将由监控bios下载到内存RAM的地址（0000:2000）
start:
;------------------------------------------------------
;init part
;------------------------------------------------------
mov ax,0
mov ds,ax
mov ss,ax
mov sp,1fffh
;---------------------------------------------------------
;8255 init
;---------------------------------------------------------
call _8255_init
;mov al,[LED_CODE]
;mov dx,_8255_porta
;out dx,al
;mov al,0feh
;mov dx,_8255_portb
;out dx,al
st001:
nop
call _8255_disp
call _8255_key
;-----------------------------------------------------
;点亮系统板上的LED
;-----------------------------------------------------
;MOV DX,800H ;800H是板子上8个LED的端口地址号
mov dx,led_port
MOV AL,0aaH ;一亮一灭间隔点亮
OUT DX,AL
call DELAY
;MOV DX,800H ;800H是板子上8个LED的端口地址号
mov dx,led_port
MOV AL,00H ;一亮一灭间隔点亮
OUT DX,AL
call DELAY
mov ah,'$'
call SEND
; lea di,STR1 ;nasm编译器不认
mov di, STR1
CALL STR_OUT
mov di, STR3
CALL STR_OUT
;mov al,01010101b
;mov al,0f0h;
;out 25H,al
;hlt
jmp st001
jmp start
;------------------------------------------------------------
; DELAY PROC NEAR
;------------------------------------------------------------
;push
DELAY:
PUSH CX
PUSH BX
NOP
NOP
mov bx,10
del1:
mov cx,5882
del2:
loop del2
dec bx
jnz del1
;pop cx
;pop bx
POP BX
POP CX
RET
;-------------------------------------------
;pc16550 uart send by AH
;-------------------------------------------
LSTAT EQU 1F5H
DAT_165 EQU 1F0H
SEND: ; PROC NEAR
MOV DX,LSTAT
WAITx:
IN AL,DX
TEST AL,20H
JZ WAITx
MOV AL,AH
MOV DX,DAT_165
OUT DX,AL
RET
;SEND ENDP
;-------------------------------------------
;串口打印字符串
;-------------------------------------------
STR_OUT :; PROC NEAR
nop; LEA DI,STR1
STR_LOOP:
;MOV AH,BYTE PTR [DI]
mov ah,byte [di]
CMP AH,'$'
JZ STR_EXIT
CALL SEND
INC DI
JMP STR_LOOP
STR_EXIT: NOP
RET
;-----------------------------
;8255 init
;-----------------------------
_8255_init:
;mov dx,203h
mov dx, _8255_port3
;mov al,80h
mov al,89h;port a,b as output port c as input
out dx,al
ret
_8255_disp:
;bit 0
mov al,[LED_CODE]
mov dx,_8255_porta
out dx,al
;mov al,0feh
mov al, 011111110b
mov dx,_8255_portb
out dx,al
call DELAY
;bit 1
mov al,[LED_CODE+1]
mov dx,_8255_porta
out dx,al
;mov al,0feh
mov al, 011111101b
mov dx,_8255_portb
out dx,al
call DELAY
;bit 2
mov al,[LED_CODE+2]
mov dx,_8255_porta
out dx,al
;mov al,0feh
mov al, 011111011b
mov dx,_8255_portb
out dx,al
call DELAY
;bit 3
mov al,[LED_CODE+3]
mov dx,_8255_porta
out dx,al
;mov al,0feh
mov al, 011110111b
mov dx,_8255_portb
out dx,al
call DELAY
;bit 4
mov al,[LED_CODE+4]
mov dx,_8255_porta
out dx,al
;mov al,0feh
mov al, 011101111b
mov dx,_8255_portb
out dx,al
call DELAY
;bit 5
mov al,[LED_CODE+5]
mov dx,_8255_porta
out dx,al
;mov al,0feh
mov al, 011011111b
mov dx,_8255_portb
out dx,al
call DELAY
;bit 6
mov al,[LED_CODE+6]
mov dx,_8255_porta
out dx,al
;mov al,0feh
mov al, 010111111b
mov dx,_8255_portb
out dx,al
call DELAY
;bit 7
mov al,[LED_CODE+7]
mov dx,_8255_porta
out dx,al
;mov al,0feh
mov al, 001111111b
mov dx,_8255_portb
out dx,al
call DELAY
ret
;------------------------------------------
;8255 key
;------------------------------------------
_8255_key:
MOV DX,202H
IN AL,DX
TEST AL,01H
JNZ NO_KEY
;INC KEY_CNT
mov di, STR4
CALL STR_OUT
NO_KEY:
NOP
ret
;STR_OUT ENDP
STR1 DB 'i8088-HELLO boy or girl!' ,13,10,'$'
STR2 DB 0AH,0DH,' ',0dh,0ah,'$'
STR3 db 'ex005---8255 key demo',13,10,'$'
STR4 db 'key0 event happen!',13,10,'$'
LED_CODE db 0C0h,0F9h,0A4H,0B0H,99H,92H,82H,0F8H,80H,90H
db 55h,55h,55h,55h,55h,55h ;程序结束标志，监控bios程序，收到后自动跳转到内存0000:2000处执行
;----------------------------------------------------------------------------------------------
