OCMJ4X8C的ASM驱动.doc

;到百度文库搜7920的驱动，都是C版的，只好自己写了个ASM版的 ;写得很简单，主要目的是点亮屏，显示一首诗 - 调试通过了 ;ASM找字库很麻烦，我用C设断点找的;OCMJ4X8C 7920控制器，128*64带字库LCD LCD_RS equ P1.5 LCD_RW equ P1.6 LCD_EN equ P1.7 LCD_Port equ P0 ;RCheck equ P1.2 ;用于蜂鸣器 org 0000H jmp start org 0100Hstart: mov sp,#060H call LCD_Init ;LCD初始化start1: call first call second call third call fourth jmp $;start1DelayMs: ;延时时间放在r6 mov r7,#0ffH djnz r7,$ djnz r6,DelayMs retLcd_ChkBusy: ;检查LCD是否忙 clr LCD_RS setb LCD_RW clr LCD_EN setb LCD_EN Lcd_ChkBsy_1: mov a,LCD_Port jb acc.7,Lcd_ChkBsy_1 clr LCD_EN clr LCD_RS setb LCD_RW retLcd_SendCmd: ;写命令。命令存放在r1 call Lcd_ChkBusy clr Lcd_RS clr LCD_RW clr LCD_EN mov LCD_Port,r1 nop nop setb LCD_EN nop nop clr LCD_EN setb LCD_RW clr LCD_RS retLCD_Init: ;屏初始化 mov r1,#30H call LCD_SendCmd ;基本指令集 mov r5,#05H call DelayMs mov r1,#01H call LCD_SendCmd ;清屏 mov r5,#05H call DelayMs mov r1,#06H call LCD_SendCmd ;光标右移 mov r5,#05H call DelayMs mov r1,#0cH call LCD_SendCmd ;开显示 retLCD_SetAdd: ;定位地址 ;r1为列地址，r2为行地址 mov a,r2 anl a,#00000011B jnz LCD_SetAdd_2 clr c mov a,r1 add a,#80H mov r1,a call LCD_SendCmd jmp LCD_SetAdd_end LCD_SetAdd_2: dec a jnz LCD_SetAdd_3 clr c mov a,r1 add a,#90H mov r1,a call LCD_SendCmd jmp LCD_SetAdd_end LCD_SetAdd_3: dec a jnz LCD_SetAdd_4 clr c mov a,r1 add a,#88H mov r1,a call LCD_SendCmd jmp LCD_SetAdd_end LCD_SetAdd_4: clr c mov a,r1 add a,#98H mov r1,a call LCD_SendCmd LCD_SetAdd_end: retLCD_SendData: ;写字符 ;要写入的数据放在r5 call Lcd_ChkBusy setb LCD_RS clr LCD_RW clr LCD_EN mov LCD_port,r5 nop nop setb LCD_EN nop nop clr LCD_EN setb LCD_RW clr LCD_RS retfirst: ; mov r1,#00H mov r2,#00H call LCD_SetAdd mov dptr,#one mov r2,#0eH mov r3,#00H jmp xianshisecond: ; mov r1,#00H mov r2,#01H call LCD_SetAdd mov dptr,#two mov r2,#0eH mov r3,#00H jmp xianshithird: ; mov r1,#00H mov r2,#02H call LCD_SetAdd mov dptr,#three mov r2,#0eH mov r3,#00H jmp xianshifourth: ; mov r1,#00H mov r2,#03H call LCD_SetAdd mov dptr,#four mov r2,#0eH mov r3,#00H jmp xianshi xianshi: mov a,r3 movc a,a+dptr mov r5,a call LCD_SendData inc r3 djnz r2,xianshi ret ;字符表ONE: DB 0c1H,0bdH,0b8H,0F6H,0bbH,0c6H,0f0H,0bfH,0c3H,0f9H,0b4H,0e4H,0c1H,0f8HTWO: DB 0d2H,0bbH,0d0H,0d0H,0b0H,0d7H,0f0H,0d8H,0c9H,0cfH,0c7H,0e0H,0ccH,0ecHTHREE: DB 0b4H,0b0H,0baH,0acH,0ceH,0f7H,0c1