STATUS   EQU         3H
FSR         EQU         4H
RB           EQU         6H
RC           EQU         7H
OPTIONA EQU         81H
TRISB     EQU         86H
TRISC     EQU         87H

GENR0     EQU         053H
GENR1     EQU         054H
WD_RG     EQU         055H
DA_AG0   EQU         056H           ;SEG0 SEG1
DA_AG8   EQU         05EH           ;SEG16 SEG17
;.............................
C             EQU         0
Z             EQU         2
RP0         EQU         5
RP1         EQU         6
CS           EQU         2      
WDA         EQU         5         ;RC,5数据线
WCLK       EQU         1         ;RB,1写时钟线
RCLK       EQU         4         ;RB,4读时钟线
;..............................
  ORG         0H
  GOTO       START
;...............................
START     BSF         STATUS,RP0
               MOVLW     00H
               MOVWF     TRISB
               MOVLW     81H
               MOVWF     TRISC
               BCF         STATUS,RP0
               MOVLW     12H
               MOVWF     RB
               BSF         RC,2
               BSF         RC,5
               MOVLW     4
               MOVWF     OPTIONA
LOOP       NOP
               CALL   X_QUAN
               NOP
               GOTO     LOOP

;............................

X_QUAN          
               MOVLW     8H        
               CALL       ON_LCD     ;TRANSMIT TH1621 WORK MODE VALUE                  
                                  
               MOVLW     9H             ;显示9位LCD  
               CALL       DIS_DATA
            
               RETURN
;............................
ON_LCD   MOVWF  GENR1
               BCF         RC,2
               MOVLW  80H           ;HI_W3 BITS:100
               MOVWF  WD_RG              
               MOVLW  3               ;3位命令100
                CALL  TRAM_DATA            
               ON_LCD0  MOVF  GENR1,0
               CALL  ON_VALUE     ;查表初始化LCD
                MOVWF  WD_RG

  MOVLW  8                               ;送8位查表值
               CALL  TRAM_DATA
      
               BCF         RC,WDA
               NOP
               NOP
               BCF         RB,1
               NOP
               NOP
               BSF         RB,1
               BSF         RC,2
  DECFSZ  GENR1,1
  GOTO  ON_LCD+1            
  RETURN
;........................
ON_VALUE
  ADDWF  2
  NOP
  RETLW  03H  ;LCD ON
  RETLW  01H  ;SYS ON

  RETLW  08H  ;TONE OFF
  RETLW  29H  ;BISA1/3   4 COM          
  RETLW  18H  ;256K                      
  RETLW  05H  ;WDT DISABLE

  RETLW  80H  ;/IRQ DISABLE   *
  RETLW  0E3H  ;NORMAL MODE     *

;................................
;TRANSMIT BITS SUBROUTINE
TRAM_DATA  
  BCF         STATUS,0        
  MOVWF  GENR0            
  BCF  RB,1              
  RLF  WD_RG              
  BTFSS  3,0
  GOTO  $+3
  BSF  RC,WDA
  GOTO  $+2
  BCF  RC,WDA
                                    
  BSF  RB,1            
  DECFSZ  GENR0,1
  GOTO  TRAM_DATA+2
                          
  RETURN
;.......................

DIS_DATA            
  MOVWF  GENR1     ;9位LCD
  BCF         RC,2
  MOVLW  0A0H
  MOVWF  WD_RG  ;WRITE CONTROL

  MOVLW  3H           ;3位写命令101
  CALL  TRAM_DATA            
  MOVLW  00
  MOVWF  WD_RG       ;WRITE ADDRESS
  MOVLW  6H             ;6位地址  
  CALL  TRAM_DATA ;                          
DIS_DATA0
  
  MOVLW  0FFH
  MOVWF  WD_RG  ;DISPLAY CODE

  MOVLW  8             ;8段数据
  CALL  TRAM_DATA

  DECFSZ  GENR1,1  
  GOTO  DIS_DATA0
  BSF         RC,2
  RETLW  0
  END