AVR单片机滤波程序

lvbo3:ldi Yl,$90            ;暂存队列首地址为$090
      ldi Yh,$00
      ldi r16,8          
      mov r4,r16            ;取暂存队列长度为16个单元,共8个数据
aa:   rcall t1ms            ;读取8个数据到缓冲区
      in r16,adcl     
      in r17,adch
      st Y+,r16
      st Y+,r17 
      dec r4
      brne aa
bb:   ldi r16,7             ;外循环比较7次         
      mov r2,r16            
bb0:  ldi r16,7          
      mov r3,r16            ;内循环比较7次
      ldi Yl,$90            ;对8个测量值排序
      ldi Yh,$00
bb1:  ld  r16,Y+
      ld  r17,Y+
      ld  r18,Y+
      ld  r19,Y+
      cp  r16,r18
      cpc r17,r19
      brsh cc                ;若数据大小逆序则交换
      dec Y
      dec Y
      dec r3
      brne bb1
      rjmp dd
cc:   push Yl               ;交换相邻两个值