cI|:1004-5422(2008)04-0326-05CAN9LCSMA CAPetriy#?s陆洁1, 刘晓天2(1.江苏教育学院宿迁分院宿迁高等师范学校, 江苏宿迁223800;2.盐城纺织职业技术学院, 江苏盐城224005)K1:应用确定与随机Petri网DSPN,对采用CSMA/CA协议的CAN总线通信过程进行建模,构建一个简化的紧缩模型,通过仿真实验得出吞吐量S、平均延迟D及消息成功传输概率P等性能参数,揭示CAN总线工作的统计规律.1oM:CAN总线;确定与随机Petri网;性能;CSMA CAms|:TP393DSM:A0CAN(ControllerAreaNetwork)9LSBosch%CB,ZL9V|I|M?h.I?hNmH,|,InA5)h?8?5)h9L,|5)l:2008-05-31.Te:d(1980 ),o,V,=,VY9/.hNmhN1,2,m-1、5)hNmhNm+1,m+2,nsYjr.,CANGh5)$s3r().m1,oP1V5)hNmhN1,2,m-1,P2V5)mhNm ,P3V5)hNmhNm+1,m+2,n.IniHBh?,oP4,P5,P6sYVU5)hh.HWM%t1、t2、t3sYVU5)h3,Lh3HW(i(i=1,2,3)s, (packets s),iL=f7.m,1,n-m-1T(),sYVUr()5)hKv,9Q)hKv?,ivH()|+)h,NH()?.oP7(P8),P9(P10),P11sYVUX35)h,P12,P13,P14sYVUb9L|?h,HM%t4、t5、t6sY5)h3(P7,P8,P9)9L?(P12,P13,P14)V,V.L=,GLq ,HWM,+H,HM%.InH5)hi5)h,VP8t5、t6,VP10t6.6BZ,InCANBd=,HY5)hX9L.H,5)h=9L,VP14t4、t5,VP13t4.h9L,.VHW|%9Lo+q.lhV(q LC,h.V.M%t7、t8、t9sYh9L.V.,4CAN2.0A9LS,r8bytesf/,B1SOF、11ID、6e、64、15CRC3W#,100 bits,!dHo+q1 Mbps,5.HW0.0001s,M%t7、t8t9(LHW0.0001 s.2CAN9LDSPN?NLCCANDSPNy,qDSPNexpress-NGVZLLC?s.Nm,K1?hNm(D(s),(Vh39L.VHW.Nm,E(P5)VUoP5(S:,LHWM%t2(Lq(h(rq)2.LittleT6VNmh?(D,D=E(P5) 2(1-E(P5) (1)L|12F,YVDSPNexpress-NGqs,VINmh?(DsS(pack-ets s)1?S.N,|1MS1010000(packets sec)16,i|T;sY|2=50,2 =100,2 =200,i|T,NmsSV(V1)Nmh(DV(V2).2.1s(S)s5)hN1,2,m-1,hrq1MH,NmhETM,t5EHWM.2MvH,oP9(P10)hA9v,oP8bH,9Lb=,oP9$Eh|,m1t5L.h9L.,t87SL.yN,Nmhrq29vH,NmsS99F,BVV1B(1M)MtA.,Nmhrq2Mf/,5)hN1,2,m-1hrq1MvH,MHW=9L1.5)h,Nm|h$327第4期陆洁,等:CAN总线CSMA CA机制的Petri网建模及性能分析V1NmsS(packets s)21 50 100 20010 49.75111936284 99.00940661676 196.0764797904100 49.74997688214 99.00486696425 196.0585596734500 49.74436529813 98.98257204744 195.97057309911000 49.73591869554 98.94902443869 195.83826524962000 49.71247844119 98.85601630955 195.47216447513000 49.67525278965 98.70863297088 194.89454851714000 49.61391665079 98.46673441499 193.95370713295000 49.50517783215 98.04083299644 192.31902823116000 49.29820037242 97.24024107381 189.31752710427000 48.84096864682 95.51328242583 183.11484507738000 47.71588224228 91.45166182649 169.60095732968500 46.68528097984 87.90944042315 158.70358479379000 44.85426022376 81.94455817267 141.73565445399500 42.1517048523 73.77258555956 120.70163778199700 40.90923101609 70.23585835426 112.264639937910000 38.63595333359 64.08686121596 98.37849650689EoP9,YVoP13h9Mhl,K/sShl,BVV1B(2M)MtA.F4VrsMf,2MNmS1wLB(nm2).wLd,i,jsY2 =200 packets s、100packets s、50 packets s.Vm2V4A,2|,19v,Nmsm2NmS1wLBShl,wL.ywLSs,1l,5)hNmETl,Nm9LH,h+