' 1602為什么不能顯示,相位修正模式下為什么不中斷


 $regfile = "m16def.dat"
   $crystal = 8000000
   '======================================
   '配置1602LCD
   Config Lcdpin = Pin , Db4 = Portb.0 , Db5 = Portb.1 , Db6 = Portb.2 , Db7 = Portb.3 , E = Portb.4 , Rs = Portb.5
Config Lcd = 16 * 2
    Cursor Off                                              '光標(biāo)關(guān)閉
    Cls                                                     '清屏LCD
   '======================================
   '*************************************
   '定時(shí)器1為匹配輸出
   Config Timer1 = Timer , Prescale = 8 , Compare A = Toggle , Clear Timer = 0
   'Compare1a = 65000
   '定義匹配輸出為相位修正模式
   Reset Tccr1a.0
   Reset Tccr1a.1
   Set Tccr1b.4
   Reset Tccr1b.3
    Enable Interrupts
   Enable Compare1a
   On Compare1a Compare1a_irs

   '定義TOP
   Dim Pwm_t As Word                                        'PWM_T為脈沖周期
   Dim Pwm_p As Byte                                        'Pwm_p為脈沖占空比
   Dim B As Long
   Pwm_t = 2000                                             '周期為1000us
   Pwm_p = 50                                               '占空比為50%
  B = Pwm_t \ 2                                             '輸入ICR1(TOP)值
   Capture1 = B
   Locate 1 , 1
   Lcd B
   Wait 7


   B = Pwm_t \ 200
   B = B * Pwm_p
  B = Capture1 - b
  Compare1a = B
    Locate 1 , 1
   Lcd B
   Wait 7
  Ddrd = &H30

   '************************************


  ' Enable Interrupts
 '  Enable Compare1a
 '  On Compare1a Compare1a_irs

    B = &H0

   Do

   Loop

   End


   Compare1a_irs:
     Locate 1 , 1
     B = B + 1
      Lcd B
      Waitms 10
      Return