Board logo

标题: 24C02计数器实战 [打印本页]
作者: fghser    时间: 2010-10-12 09:16     标题: 24C02计数器实战

  1. ;24c02的开机计数器，系统复位或停送电一次数码管加1
  2. ;***************************************************************************
  3. ;* (程序转载请著明出处 ，www.wenqi89s51.com) *

  5. SDA24 EQU P3.6
  6. SCLK24 EQU P3.7

  8. ORG 0000H
  9. AJMP MAIN
  10. ORG 0030H
  11. MAIN:

  13. MOV SP,#70H;设置堆栈栈顶
  14. MOV DPTR,#TAB
  15. MOV A,#00H ;读地址
  16. LCALL RD24
  17. CJNE A,#10,TT
  18. TT: JNC TT1
  19. AJMP TT2
  20. TT1: MOV A,#00
  21. TT2: MOV 30H,A
  22. MOVC A,@A+DPTR
  23. CLR P2.0 ;开数码管
  24. MOV P0,A ;送显示

  26. MOV A,30H
  27. INC A
  28. MOV B,A
  29. MOV A,#00H
  30. LCALL WT24
  31. AJMP $
  32. TAB: DB 0C0H,0F9H,0A4H,0B0H,99H,92H,82H,0F8H,80H,90H;七段数码管0-9字形编码


  35. RD24: PUSH ACC ;读24C02子程序。
  36. SETB SDA24
  37. CLR SCLK24
  38. CALL START24
  39. MOV A,#0A0H
  40. CALL SHIFT8
  41. CALL ACK
  42. POP ACC
  43. CALL SHIFT8
  44. CALL ACK
  45. CALL START24
  46. MOV A,#0A1H
  47. CALL SHIFT8
  48. CALL ACK
  49. SETB SDA24
  50. MOV R7,#8
  51. CLR A
  52. SETB SDA24
  53. RD000: RL A
  54. SETB SCLK24
  55. MOV C,SDA24
  56. MOV ACC.0,C
  57. CLR SCLK24
  58. DJNZ R7,RD000
  59. RET
  60. ;-------------------------------
  61. ;写入24C02程序：
  62. WT24: PUSH ACC
  63. SETB SDA24
  64. CLR SCLK24
  65. CALL START24
  66. MOV A,#0A0H
  67. CALL SHIFT8
  68. CALL ACK
  69. POP ACC
  70. CALL SHIFT8
  71. CALL ACK
  72. MOV A,B
  73. CALL SHIFT8
  74. CALL ACK
  75. CALL STOP
  76. CALL DELAY2
  77. RET
  78. ; -------------------------------
  79. ;开始条件
  80. START24:CLR SDA24
  81. SETB SDA24
  82. SETB SCLK24
  83. CLR SDA24
  84. CLR SCLK24
  85. RET

  87. ;停止条件
  88. STOP: CLR SDA24
  89. SETB SCLK24
  90. SETB SDA24
  91. RET

  93. ;应答信号
  94. ACK: SETB SCLK24
  95. CLR SCLK24
  96. RET

  98. ;读、写数据
  99. SHIFT8: MOV R7,#8
  100. SH01: RLC A
  101. MOV SDA24,C
  102. SETB SCLK24
  103. CLR SCLK24
  104. DJNZ R7,SH01
  105. RET

  107. DELAY2:
  108. NOP
  109. NOP
  110. NOP
  111. NOP
  112. RET
  113. END
复制代码




欢迎光临 珩源工控论坛 (http://bbs.hymcu.com/) Powered by Discuz! 7.2