CAN总线硬件连接及程序.doc

学习资料收集于网络，仅供参考1. /F04x_CAN1.c 2. /- 3. / 4. / 5. /DEVICE:C8051F040 6. / 7. /AUTHOR:LS 8. / 9. /TOOLS:KeilC-compilerandSiliconLabsIDE 10. / 11. / 12. /CAN1.candCAN2.careasimpleexampleofconfiguringaCANnetworkto 13. /transmitandreceivedataonaCANnetwork,andhowtomoveinformationto 14. /andfromCANRAMmessageobjects.EachC8051F040-TBCANnodeisconfigured 15. /tosendamessagewhenitsP3.7buttonisdepressed/released,witha0x11 16. /toindicatethebuttonispushed,and0x00whenreleased.Eachnodealsohas 17. /amessageobjectconfiguredtoreceivemessages.TheC8051teststhe 18. /receiveddataandwillturnon/offthetargetboardsLED.Whenonetarget 19. /isloadedwithCAN2.candtheotherisloadedwithCAN1.c,onetarget 20. /boardspush-buttonwillcontroltheothertargetboardsLED,establishing 21. /asimplecontrollinkviatheCANbusandcanbeobserveddirectlyonthe 22. /targetboards. 23. / 24. 25. / 26. /Includes 27. / 28. 29. #include/SFRdeclarations 30. 31. /CANProtocolRegisterIndexforCAN0ADR,fromTABLE18.1oftheC8051F040 32. /datasheet 33. / 34. #defineCANCTRL0x00/ControlRegister 35. #defineCANSTAT0x01/Statusregister 36. #defineERRCNT0x02/ErrorCounterRegister 37. #defineBITREG0x03/BitTimingRegister 38. #defineINTREG0x04/InterruptLowByteRegister 39. #defineCANTSTR0x05/Testregister 40. #defineBRPEXT0x06/BRPExtensionRegister 41. / 42. /IF1InterfaceRegisters 43. / 44. #defineIF1CMDRQST0x08/IF1CommandRestRegister 45. #defineIF1CMDMSK0x09/IF1CommandMaskRegister 46. #defineIF1MSK10x0A/IF1Mask1Register 47. #defineIF1MSK20x0B/IF1Mask2Register 48. #defineIF1ARB10x0C/IF1Arbitration1Register 49. #defineIF1ARB20x0D/IF1Arbitration2Register 50. #defineIF1MSGC0x0E/IF1MessageControlRegister 51. #defineIF1DATA10x0F/IF1DataA1Register 52. #defineIF1DATA20x10/IF1DataA2Register 53. #defineIF1DATB10x11/IF1DataB1Register 54. #defineIF1DATB20x12/IF1DataB2Register 55. / 56. /IF2InterfaceRegisters 57. / 58. #defineIF2CMDRQST0x20/IF2CommandRestRegister 59. #defineIF2CMDMSK0x21/IF2CommandMaskRegister 60. #defineIF2MSK10x22/IF2Mask1Register 61. #defineIF2MSK20x23/IF2Mask2Register 62. #defineIF2ARB10x24/IF2Arbitration1Register 63. #defineIF2ARB20x25/IF2Arbitration2Register 64. #defineIF2MSGC0x26/IF2MessageControlRegister 65. #defineIF2DATA10x27/IF2DataA1Register 66. #defineIF2DATA20x28/IF2DataA2Register 67. #defineIF2DATB10x29/IF2DataB1Register 68. #defineIF2DATB20x2A/IF2DataB2Register 69. / 70. /MessageHandlerRegisters 71. / 72. #defineTRANSREQ10x40/TransmissionRest1Register 73. #defineTRANSREQ20x41/TransmissionRest2Register 74. 75. #defineNEWDAT10x48/NewData1Register 76. #defineNEWDAT20x49/NewData2Register 77. 78. #defineINTPEND10x50/InterruptPending1Register 79. #defineINTPEND20x51/InterruptPending2Register 80. 81. #defineMSGVAL10x58/MessageValid1Register 82. #defineMSGVAL20x59/MessageValid2Register 83. 84. / 85. /GlobalVariables 86. / 87. charMsgNum;88. charstatus;89. inti;90. intMOTwoIndex=0;91. intMOOneIndex=0;92. intStatusCopy;93. intRXbuffer4;94. intTXbuffer8;95. intMsgIntNum;96. intTemperature;97. sbitBUTTON=P37;98. sbitLED=P16;99. sfr16CAN0DAT=0xD8;100. 101. 102. 103. / 104. /FunctionPROTOTYPES 105. / 106. 107. /InitializeMessageObject 108. voidclear_msg_objects(void);109. voidinit_msg_object_TX(charMsgNum);110. voidinit_msg_object_RX(charMsgNum);111. voidstart_CAN(void);112. voidtransmit_turn_LED_ON(charMsgNum);113. voidtransmit_turn_LED_OFF(charMsgNum);114. voidreceive_data(charMsgNum);115. voidexternal_osc(void);116. voidconfig_IO(void);117. voidflash_LED(void);118. voidtest_reg_write(chartest);119. voidstop_CAN(void);120. 121. 122. / 123. /MAINRoutine 124. / 125. voidmain(void)126. 127. /disablewatchdogtimer 128. WDTCN=0xde;129. WDTCN=0xad;130. 131. /configurePortI/O 132. config_IO();133. 134. /switchtoexternaloscillator 135. external_osc();136. 137. 138. / 139. /ConfigureCANcommunications 140. / 141. /IF1usedforprocedurescallesbymainprogram 142. /IF2usedforinterruptserviceprocedurereceive_data 143. / 144. /MessageObjectassignments: 145. /0x02:UsedtotransmitcommandstotoggleitsLED,arbitrationnumber1 146. / 147. / 148. 149. /ClearCANRAM 150. clear_msg_objects();151. 152. /Initializemessageobjecttotransmitdata 153. init_msg_object_TX(0x02);154. 155. /Initializemessageobjecttoreceivedata 156. init_msg_object_RX(0x01);157. 158. /EnableCANinterruptsinCIP-51 159. EIE2=0x20;160. 161. /FunctioncalltostartCAN 162. start_CAN();163. 164. /Globalenable8051interrupts 165. EA=1;166. 167. /Loopandwaitforinterrupts 168. while(1)169. 170. if(BUTTON=0)171. while(BUTTON=0)172. transmit_turn_LED_OFF(0x02);173. else174. while(BUTTON=1)175. transmit_turn_LED_ON(0x02);176. 177. 178. 179. 180. / 181. /SetupC8051F040 182. / 183. 184. /Switchtoexternaloscillator 185. voidexternal_osc(void)186. 187. intn;/localvariableusedindelayFORloop. 188. SFRPAGE=CONFIG_PAGE;/switchtoconfigpagetoconfigoscillator 189. OSCXCN=0x77;/startexternaloscillator;22.1MHzCrystal 190. /systemclockis22.1MHz/2=11.05MHz 191. for(n=0;n255;n+);/delayabout1ms 192. while(OSCXCN&0x80)=0);/waitforoscillatortostabilize 193. CLKSEL|=0x01;/switchtoexternaloscillator 194. 195. 196. voidconfig_IO(void)197. 198. SFRPAGE=CONFIG_PAGE;/PortSFRsonConfigurationpage 199. XBR3=0x80;/ConfigureCANTXpin(CTX)aspush-pulldigitaloutput 200. P1MDOUT|=0x40;/ConfigureP1.6aspush-pulltodriveLED 201. XBR2=0x40;/EnableCrossbar/lowports 202. 203. 204. / 205. /CANFunctions 206. / 207. 208. 209. /ClearMessageObjects 210. voidclear_msg_objects(void)211. 212. SFRPAGE=CAN0_PAGE;213. CAN0ADR=IF1CMDMSK;/PointtoCommandMaskRegister1 214. CAN0DATL=0xFF;/SetdirectiontoWRITEallIFregisterstoMsgObj 215. for(i=1;i=400ns).275. Sync_Seg=1tq276. 277. Phase_seg1+Phase_Seg2=(11-6)tq=5tq278. Phase_seg1Phase_seg1=2tqandPhase_Seg2=3tq279. SJW=(min(Phase_Seg1,4)tq=2tq280. 281. TSEG1=(Prop_Seg+Phase_Seg1-1)=6282. TSEG2=(Phase_Seg2-1)=2283. SJW_p=(SJW-1)=1284. 285. BitTimingRegister=BRP+SJW_p*0x0040=TSEG1*0x0100+TSEG2*0x1000=2640286. 287. Clocktolerancedf:288. 289. A:dfmin(Phase_Seg1,Phase_Seg2)/(2*(13*bit_time-Phase_Seg2)290. B:dfSJW/(20*bit_time)291. 292. A:df2/(2*(13*11-3)=1/(141-3)=1/138=0.7246%293. B:df2/(20*11)=1/110=0.9091%294. 295. Actualclocktoleranceis0.7246%-0.5381%=0.1865%(noproblemforquartz)296. */297. 298. SFRPAGE=CAN0_PAGE;299. CAN0CN|=0x41;/ConfigurationChangeEnableCCEandINIT 300. CAN0ADR=BITREG;/PointtoBitTimingregister 301. CAN0DAT=0x2640;/seeabove 302. 303. CAN0ADR=IF1CMDMSK;/PointtoCommandMask1 304. CAN0DAT=0x0087;/ConfigforTX:WRITEtoCANRAM,writedatabytes, 305. /setTXrqst/NewDat,clrIntPnd 306. 307. /RX-IF2operationmayinterruptTX-IF1operation 308. CAN0ADR=IF2CMDMSK;/PointtoCommandMask2 309. CAN0DATL=0x1F;/ConfigforRX:READCANRAM,readdatabytes, 310. /clrNewDatandIntPnd 311. CAN0CN|=0x06;/GlobalInt.EnableIEandSIE 312. CAN0CN&=0x41;/ClearCCEandINITbits,startsCANstatemachine 313. 314. 315. /TransmitCANframetoturnothernodesLEDON 316. voidtransmit_turn_LED_ON(charMsgNum)317. 318. SFRPAGE=CAN0_PAGE;/IF1alreadysetupforTX 319. CAN0ADR=IF1CMDMSK;/PointtoCommandMask1 320. CAN0DAT=0x0087;/ConfigtoWRITEtoCANRAM,writedatabytes, 321. /setTXrqst/NewDat,ClrIntPnd 322. CAN0ADR=IF1DATA1;/Pointto1stbyteofDataField 323. CAN0DATL=0x11;/OnessignalstoturnLEDslightONindataA1field 324. CAN0ADR=IF1CMDRQST;/PointtoCommandRequestReg. 325. CAN0DATL=MsgNum;/MovenewdataforTXtoMsgObjMsgNum 326. 327. 328. /TransmitCANFrametoturnothernodesLEDOFF 329. voidtransmit_turn_LED_OFF(charMsgNum)330. 331. SFRPAGE=CAN0_PAGE;/IF1alreadysetupforTX 332. CAN0ADR=IF1DATA1;/Pointto1stbyteofDataField 333. CAN0DATL=0x00;/ZerosignalstoturnLEDslightONinDataA1field 334. CAN0ADR=IF1CMDRQST;/PointtoCommandRequestReg. 335. CAN0DATL=MsgNum;/MovenewdataforTXtoMsgObjMsgNum 336. 337. 338. 339. /ReceiveDatafromtheIF2buffer 340. voidreceive_data(charMsgNum)341. 342. charvirtual_button;343. SFRPAGE=CAN0_PAGE;/IF1alreadysetupforRX 344. CAN0ADR=IF2CMDRQST;/PointtoCommandRequestReg. 345. CAN0DATL=MsgNum;/MovenewdataforRXfromMsgObjMsgNum 346. /Movenewdatatoa 347. CAN0ADR=IF2DATA1;/Pointto1stbyteofDataField 348. 349. virtual_button=CAN0DATL;350. if(virtual_button=0x11)/OnesissignalfromothernodetoturnLEDON 351. LED=1;352. elseLED=0;/OtherwiseturnLEDOFF(messagewasones) 353. 354. 355. / 356. /InterruptServiceRoutine 357. / 358. voidISRname(void)interrupt19359. 360. status=CAN0STA;361. if(status&0x10)!=0)362. /RxOkisset,interruptcausedbyreception 363. CAN0STA=(CAN0STA&0xEF)|0x07;/ResetRxOk,setLECtoNoChange 364. /*readmessagenumberfromCANINTREG*/365. receive_data(0x01);/Uptonow,wehaveonlyoneRXmessage 366. 367. if(status&0x08)!=0)368. /TxOkisset,interruptcausedbytransmision 369. CAN0STA=(CAN0STA&0xF7)|0x07;/ResetTxOk,setLECtoNoChange 370. 371. if(status&0x07)!=0)&(status&0x07)!=7)372. /Errorinterrupt,LECchanged 373. /*e