ORG 0000H
      AJMP 0100H


;cycle=12/f=(12/12)us
      ORG 0100H
      MOV 1CH,#0FFH     ;CODE REGISTER
      mov 1ah,#0FFh
      mov 1bh,#0FFh
      mov 1dh,#0FFh
      MOV R7,#00H      ;?????
START:MOV P0,#0FFH
      MOV P1,#0FFH
      MOV P2,#0FFH
      MOV P3,#0FFH
;XXXXXXXXXXXXXXXXXXXXXXX
;X LCM44780 DISPLAY    X
;XXXXXXXXXXXXXXXXXXXXXXX
START1:
    
    RS EQU P0.0
    RW EQU P0.1
    E EQU P0.2
    mov p0,#0ffh
    MOV P2,#01H ;清除屏幕
    ACALL ENABLE
    MOV p2,#38H ;8位點陣
    ACALL ENABLE

    MOV p2,#06H ;移動光標/進入模式設定
    ACALL ENABLE
    MOV p2,#80H ;顯示位置
    MOV P2,#01H ;清除屏幕
    ACALL ENABLE
    MOV p2,#0FH ;開顯示
    ACALL ENABLE
l3: mov p2,#01h  ;清屏
    call enable

    mov p2,#0c0h   ;   設置顯示在第一行
    acall enable
    mov p2,#01h

    ACALL ENABLE
    mov dptr,#table2 ;送第一句話
    acall write1
    mov p2,#0c2h     ;顯示在第二行
    acall enable
    mov p2,#0a8h
    acall enable 
    mov dptr,#table1
    mov a,1ah        ;send 1ah data
    anl a,#0f0h
    swap a
    movc a,@a+dptr
    acall write2
    mov a,1ah
    anl a,#0fh
    movc a,@a+dptr
    acall write2
    mov a,1bh        ;send 1bh data
    anl a,#0f0h
    swap a
    movc a,@a+dptr
    acall write2
    mov a,1bh
    anl a,#0fh
    movc a,@a+dptr
    acall write2
    mov a,1ch        ;send 1ch data
    anl a,#0f0h
    swap a
    movc a,@a+dptr
    acall write2
    mov a,1ch
    anl a,#0fh
    movc a,@a+dptr
    acall write2
    mov a,1dh        ;send 1dh data
    anl a,#0f0h
    swap a
    movc a,@a+dptr
    acall write2
    mov a,1dh
    anl a,#0fh
    movc a,@a+dptr
    acall write2

    
;XXXXXXXXXXXXXXXXXXXXXXXXX
int0: jb p3.2,int0
      MOV R6,#0AH
SB:   ACALL YS1          ;調用882微秒延時子程序
      JB P3.2,exit       ;延時882微秒后判斷P3.2腳是否出現高電平如果有就退出解碼程序
      DJNZ R6,SB         ;重復10次，目的是檢測在8820微秒內如果出現高電平就退出解碼程序
;以上完成對遙控信號的9000微秒的初始低電平信號的識別。
      JNB P3.2,$         ;等待高電平避開9毫秒低電平引導脈沖
      ACALL YS2          ;延時4.74毫秒避開4.5毫秒的結果碼
      JB P3.2,EXIT
      MOV R1,#1AH
      MOV R2,#4
PP:   MOV R3,#8
JJJJ: JNB P3.2,$
      LCALL YS1
      MOV C,P3.2
      JNC UUU
      JB P3.2,$
UUU:  MOV A,@R1
      RRC A
      MOV @R1,A
      DJNZ R3,JJJJ
      INC R1
      DJNZ R2,PP
      MOV A,1AH
      XRL A,#00000000B
      JNZ EXIT
      MOV A,1BH
      XRL A,#11111111B
      JNZ EXIT
      MOV A,1CH
      CPL A
      XRL A,1DH
      JNZ EXIT

;XXXXXXXXXXXXXXXXXXXXXXXXX
AA:   MOV R1,#25
XX:   ACALL YS2
      JNB p3.2,HH
      DJNZ R1,XX
EXIT:  setb p3.2
       ajmp start1
HH:  MOV R6,#4
S:   ACALL YS1
     JB P3.2,EXIT
     DJNZ R6,S
     JNB P3.2,$
     ACALL YS3
     AJMP AA



;xxxxxxxxxxxxxxxxxxxxxxxxx

;YS1
YS1:  MOV R4,#20       ;DELAY 882US
D1:   MOV R5,#20
      
D11:  
      DJNZ R5,D11
      DJNZ R4,D1
      RET

;YS2
YS2:  MOV R4,#10       ;DELAY 4740US
D2:   MOV R5,#235
      
      DJNZ R5,$
      DJNZ R4,D2
      RET

YS3: MOV R4,#2         ;DELAY 1000US
DD3: MOV R5,#248
     DJNZ R5,$
     DJNZ R4,D3
     RET

;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
ENABLE: ;送命令
   CLR RS      ;rs=0 send command
   CLR RW
   CLR E
   ACALL DELAY
   SETB E
   RET
write1:            ;送字符串
   mov r1,#00h
a1:mov a,r1
   movc a,@a+dptr
   call write2
   inc r1
   cjne a,#3ah,a1 ;以3aH做字符串結束標志
   ret
write2:           ;送單個字符
   mov p2,a
   setb rs        ;rs=1 send data
   clr rw
   clr e
   call delay
   setb e
   ret
delay:            ;延時子程序

d3:mov r7,#10
dd1:mov r6,#255
dd2:nop
   nop
   nop
   nop
   nop
   djnz r6,dd2
   djnz r7,dd1
   ret

table1: db 30h,31h,32h,33h,34h,35h,36h,37h,38h,39h,41h,42h,43h,44h,45h,46h
table2: db 54h,48h,49h,53h,20h,4bh,45h,59h,20h,43h,4fh,44h,45h,3ah
end