Board logo

标题: 51 IO口模拟串口通讯C源程序 [打印本页]
作者: leslen    时间: 2010-10-13 18:15     标题: 51 IO口模拟串口通讯C源程序

  1. #include <reg51.h>
  2. sbit BT_SND =P1^0;
  3. sbit BT_REC =P1^1;
  4. /**********************************************

  6. IO 口模拟232通讯程序

  8. 使用两种方式的C程序 占用定时器0

  10. **********************************************/

  12. #define MODE_QUICK

  14. #define F_TM F0

  16. #define TIMER0_ENABLE TL0=TH0; TR0=1;
  17. #define TIMER0_DISABLE TR0=0;

  19. sbit ACC0= ACC^0;
  20. sbit ACC1= ACC^1;
  21. sbit ACC2= ACC^2;
  22. sbit ACC3= ACC^3;
  23. sbit ACC4= ACC^4;
  24. sbit ACC5= ACC^5;
  25. sbit ACC6= ACC^6;
  26. sbit ACC7= ACC^7;

  28. void IntTimer0() interrupt 1
  29. {
  30. F_TM=1;
  31. }
  32. //发送一个字符
  33. void PSendChar(unsigned char inch)
  34. {
  35. #ifdef MODE_QUICK
  36. ACC=inch;

  38. F_TM=0;
  39. BT_SND=0; //start bit
  40. TIMER0_ENABLE; //启动
  41. while(!F_TM);

  43. BT_SND=ACC0; //先送出低位
  44. F_TM=0;
  45. while(!F_TM);

  47. BT_SND=ACC1;
  48. F_TM=0;
  49. while(!F_TM);

  51. BT_SND=ACC2;
  52. F_TM=0;
  53. while(!F_TM);

  55. BT_SND=ACC3;
  56. F_TM=0;
  57. while(!F_TM);

  59. BT_SND=ACC4;
  60. F_TM=0;
  61. while(!F_TM);

  63. BT_SND=ACC5;
  64. F_TM=0;
  65. while(!F_TM);

  67. BT_SND=ACC6;
  68. F_TM=0;
  69. while(!F_TM);

  71. BT_SND=ACC7;
  72. F_TM=0;
  73. while(!F_TM);

  75. BT_SND=1;
  76. F_TM=0;
  77. while(!F_TM);


  80. TIMER0_DISABLE; //停止timer
  81. #else
  82. unsigned char ii;

  84. ii=0;

  86. F_TM=0;
  87. BT_SND=0; //start bit
  88. TIMER0_ENABLE; //启动
  89. while(!F_TM);

  91. while(ii<8)
  92. {
  93. if(inch&1)
  94. {
  95. BT_SND=1;
  96. }
  97. else
  98. {
  99. BT_SND=0;
  100. }
  101. F_TM=0;
  102. while(!F_TM);
  103. ii++;
  104. inch>>=1;
  105. }
  106. BT_SND=1;
  107. F_TM=0;
  108. while(!F_TM);

  110. #endif
  111. TIMER0_DISABLE; //停止timer
  112. }
  113. //接收一个字符
  114. unsigned char PGetChar()
  115. {
  116. #ifdef MODE_QUICK

  118. TIMER0_ENABLE;
  119. F_TM=0;
  120. while(!F_TM); //等过起始位
  121. ACC0=BT_REC;

  123. TL0=TH0;

  125. F_TM=0;
  126. while(!F_TM);
  127. ACC1=BT_REC;

  129. F_TM=0;
  130. while(!F_TM);
  131. ACC2=BT_REC;

  133. F_TM=0;
  134. while(!F_TM);
  135. ACC3=BT_REC;

  137. F_TM=0;
  138. while(!F_TM);
  139. ACC4=BT_REC;

  141. F_TM=0;
  142. while(!F_TM);
  143. ACC5=BT_REC;

  145. F_TM=0;
  146. while(!F_TM);
  147. ACC6=BT_REC;

  149. F_TM=0;
  150. while(!F_TM);
  151. ACC7=BT_REC;

  153. F_TM=0;

  155. while(!F_TM)
  156. {
  157. if(BT_REC)
  158. {
  159. break;
  160. }
  161. }
  162. TIMER0_DISABLE; //停止timer
  163. return ACC;
  164. #else
  165. unsigned char rch,ii;
  166. TIMER0_ENABLE;
  167. F_TM=0;
  168. ii=0;
  169. rch=0;
  170. while(!F_TM); //等过起始位

  172. while(ii<8)
  173. {
  174. rch>>=1;
  175. if(BT_REC)
  176. {
  177. rch|=0x80;
  178. }
  179. ii++;
  180. F_TM=0;
  181. while(!F_TM);

  183. }
  184. F_TM=0;
  185. while(!F_TM)
  186. {
  187. if(BT_REC)
  188. {
  189. break;
  190. }

  192. }
  193. TIMER0_DISABLE; //停止timer
  194. return rch;

  196. #endif

  198. }
  199. //检查是不是有起始位
  200. bit StartBitOn()
  201. {
  202. return (BT_REC==0);

  204. }
  205. void main()
  206. {
  207. unsigned char gch;

  209. TMOD=0x22; /*定时器1为工作模式2(8位自动重装)，0为模式2(8位
  210. 自动重装) */
  211. PCON=00;

  213. TR0=0; //在发送或接收才开始使用
  214. TF0=0;
  215. TH0=(256-96); //9600bps 就是 1000000/9600=104.167微秒 执行的
  216. timer是
  217. //
  218. 104.167*11.0592/12= 96
  219. TL0=TH0;
  220. ET0=1;
  221. EA=1;

  223. PSendChar(0x55);
  224. PSendChar(0xaa);
  225. PSendChar(0x00);
  226. PSendChar(0xff);

  228. while(1)
  229. {
  230. if(StartBitOn())
  231. {
  232. gch=PGetChar();
  233. PSendChar(gch);
  234. }
  235. }

  237. }
复制代码




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