.include "m8def.inc"
            .org      $00   
            rjmp     main
            .org     $20
main:       ldi      r16,high(ramend)
            out      sph,r16
            ldi      r16,low(ramend) 
            out      spl,r16
            sbi      ddrc,1
            cbi      portc,1     ;pc1為液晶的數據/指令線(RS)
            sbi      ddrb,3
            sbi      portb,3     ;pb3為74hc164的數據線(A,B)
            sbi      ddrb,2
            sbi      portb,2     ;pb2為74hc164的時鐘線(CLK)
            sbi      ddrc,2
            cbi      portc,2     ;pc2為液晶的片選線,高電平有效(E)
            ldi      r18,0
loop:       ldi      r31,4
            mov      r30,r18
            lpm      r16,z
            call     yiwei
            call     delay1
            inc      r18
            cpi      r18,6
            brlo     loop
            ldi      r16,$80
            call     yiwei
            call     delay1
            sbi      portc,1
            ldi      r16,$33 
            call     yiwei  
            call     delay1
            ldi      r16,$34 
            call     yiwei 
            call     delay1
            ldi      r16,$35
            call     yiwei
            call     delay1
wait:       rjmp     wait  
;************************************************          
yiwei:      ldi      r17,8
yiwei0:     sbi      portb,3
            rol      r16         ;r16為要移位的數
            brcs     yiwei1
            cbi      portb,3      
yiwei1:     cbi      portb,2
            sbi      portb,2     ;時鐘線置1,送出數據
            dec      r17
            cpi      r17,1
            brsh     yiwei0
          ;  sbi      portc,2    ;液晶片選置1,給液晶送入數據
          ;  cbi      portc,2
            sbi      portc,2    ;液晶片選置1,給液晶送入數據
            cbi      portc,2
            ret  
;*******************************************            
delay1:     ldi      r16,20
del1:       ldi      r17,255
del2:       dec      r17
            cpi      r17,1
            brsh     del2
            dec      r16
            cpi      r16,1
            brsh     del1
            ret  
;***********************************************************************
.org    $200 ;液晶初始化的值
        .db  $01,$03,$06,$0f,$14,$3c