keil c51红外遥控解码程序

解码思路:

红外线经一体化接受头解码放到后送到单片机的外部中断0,单片机设置外部中断下降沿触发,T0和T1为16位定时器,T0在系统启动后定时5ms.T1在外部中断0启动后开始定时,初值为0,每次在INT0中断后先读T1计数值,并重设初值为0,而且判断T1的计数值,

1. //Fosc=11.0592MHz
2. //statesforandvariablesIRdataprocessing
3. typedefenum{
4. IR_idle,
5. IR_waitstart,
6. IR_getaddr,
7. IR_getaddrinv,
8. IR_getdata,
9. IR_getdatainv
10. }_IRstate
11.  
12. _IRstateIRstate=IR_idle
13.  
14. unsignedcharIRaddr=0xff
15. unsignedchar_IRaddr=0xff
16. unsignedcharIRdata=0xff
17. unsignedchar_IRdata=0xff
18. unsignedcharIR_repeat=0
19. unsignedcharIR_ready=0
20. unsignedcharIR_poweron=0
21. //bitir_done=0
22. //timeconstants
23. unsignedintIRtimer=0//IRtimeout
24.  
25. //cpu初始化
26. voidcpu_init(void)
27. {
28. TMOD=0X11//T0andT1十六位定时
29. TH0=0xee//fosc=11.0592M,timer=5ms
30. TL0=0x00
31. TR0=1//runtimer0
32. TF0=0
33.  
34. ET0=1//enabletmr0overflowinterrupt
35. IT0=1//int0edgesensitive
36. EX0=1//enable"int0"
37. EA=1//globalinteruptenable
38. }
39.  
40. //T0中断
41. voidtmrint()interrupt1
42. {
43. TH0=0xee
44. TL0=0x00
45. if(IRtimer)//IR接收超时
46. --IRtimer//
47. else
48. {
49. IRstate=IR_idle
50. //IR_poweron=0
51. }
52. }
53.  
54. //Fosc=11.0592MHz
55. #definemsec_12p50x2d00
56. #definemsec_150x3600
57. #definemsec_90x2066
58. //#definemsec_90x1066
59. #definemsec_2p50x900
60. #definemsec_0p90x33d
61. #definemsec_1p680x610
62.  
63.  
64. //voidIRint()interrupt0(void)
65.  
66. //WhentheIRreceivepingoeslowandinterruptisgenerated
67. //IRiscollectedbystartingtimer2inthefirstfallingedgeofthepin
68. //thenoneveryotherfallingedge,thetimervalueissavedandthetimerrestarted.
69. //thecapturedtimeisthenusedtogettheIRdata
70. //a"startofdata"is13.5Msec,a"1"is2.25Msec,a"0"is1.12msecanda"repeat"is11.25msec.
71. //thecounterincrementsat1.085Usec
72. //Iallowafairlylargetolerancetotimejitterbuttherearenofalsetriggersseen.
73.  
74. voidIRint()interrupt0
75. {
76. staticunsignedcharbits
77. unsignedshorttime
78. switch(IRstate)
79. {
80. caseIR_idle:
81. TL1=0
82. TH1=0
83. TR1=1
84. IRstate=IR_waitstart
85. IRtimer=26
86. break
87. caseIR_waitstart://P2_4=!P2_4
88. TR1=0
89. time=TH1
90. time=(time<<8)+TL1
91. TL1=0
92. TH1=0
93. TR1=1
94. if((time>msec_12p5)&&(time
95. {
96. IRaddr=0
97. _IRaddr=0
98. IRdata=0
99. _IRdata=0
100. bits=1
101. IRstate=IR_getaddr
102. }
103. elseif((time>msec_9)&&(time
104. {
105. IR_repeat=2
106. IRstate=IR_idle
107. }
108. else
109. {//toshort,baddatajustgotoidle
110. IRstate=IR_idle
111. }
112. break
113. caseIR_getaddr://P2_4=!P2_4
114. TR1=0
115. time=TH1
116. time=(time<<8)+TL1
117. TL1=0
118. TH1=0
119. TR1=1
120. if((time>msec_2p5)||(time2.5msecorshorterthan.9Msecbaddata,gotoidle
121. {
122. IRstate=IR_idle
123. break
124. }
125. if(time>msec_1p68)//greaterthan1.68Msecisa1
126. {
127. IRaddr|=bits
128. }
129. bits=bits<<1
130. if(!bits)
131. {
132. IRstate=IR_getaddrinv
133. bits=1
134. }
135. break
136. caseIR_getaddrinv://P2_4=!P2_4
137. TR1=0
138. time=TH1
139. time=(time<<8)+TL1
140. TL1=0
141. TH1=0
142. TR1=1
143. if((time>msec_2p5)||(time2.5msecorshorterthan.9Msecbaddata,gotoidle
144. {
145. IRstate=IR_idle
146. break
147. }
148. if(time>msec_1p68)//greaterthan1.68Msecisa1
149. {
150. _IRaddr|=bits
151. }
152. bits=bits<<1
153. if(!bits)
154. {
155. IRstate=IR_getdata
156. bits=1
157. }
158. break
159. caseIR_getdata:
160. TR1=0
161. time=TH1
162. time=(time<<8)+TL1
163. TL1=0
164. TH1=0
165. TR1=1
166. if((time>msec_2p5)||(time2.5msecorshorterthan.9Msecbaddata,gotoidle
167. {
168. IRstate=IR_idle
169. break
170. }
171. if(time>msec_1p68)//greaterthan1.68Msecisa1
172. {
173. IRdata|=bits
174. }
175. bits=bits<<1
176. if(!bits)
177. {
178. IRstate=IR_getdatainv
179. bits=1
180. }
181. break
182. caseIR_getdatainv:
183. TR1=0
184. time=TH1
185. time=(time<<8)+TL1
186. TL1=0
187. TH1=0
188. TR1=1
189. if((time>msec_2p5)||(time2.5msecorshorterthan.9Msecbaddata,gotoidle
190. {
191. IRstate=IR_idle
192. break
193. }
194. if(time>msec_1p68)//greaterthan1.68Msecisa1
195. {
196. _IRdata|=bits
197. }
198. bits=bits<<1
199. if(!bits)//wehaveitall,nowwemakesureitisaNECcodefromtheCHSIRtransmitter
200. {//makesureaddress,~addressarecorrect,data,~dataarecorrectandaddressis0.
201. IR_ready=((IRaddr^_IRaddr)==0xff)&&((IRdata^_IRdata)==0xff)&&(IRaddr==0)
202. if(IR_ready)
203. {
204. IRstate=IR_idle
205. }
206. }
207. break
208. default:
209. IRstate=IR_idle
210. break
211. }
212. }
213.  
214. voidmain(void)
215. {
216. cpu_init()
217. while(1)
218. {
219. if(IR_ready)
220. {
221. IR_ready=0
222. switch(IRdata)
223. {
224. case0x45://1
225. //yourcode
226. break
227. case0x44://3
228. //yourcode
229. break
230. case0x43://4
231. //yourcode
232. break
233. case0x08://prev
234. //yourcode
235. break
236. case0x5a://next
237. //yourcode
238. break
239. default:
240. break
241. &n bsp}
242. }
243. }
244. }