matlab j1939 通信快速入门 -凯发k8网页登录

此示例说明如何创建和使用 j1939 通道在 j1939 网络上传输和接收参数组。此示例使用数据库文件 j1939.dbc 和以环回配置连接的 mathworks® 虚拟 can 通道。

打开 dbc 文件

使用打开 dbc 文件以访问定义。

db = candatabase("j1939.dbc")

db = 
  database with properties:
             name: 'j1939'
             path: 'c:\users\michellw\onedrive - mathworks\documents\matlab\examples\vnt-ex33605241\j1939.dbc'
            nodes: {2×1 cell}
         nodeinfo: [2×1 struct]
         messages: {2×1 cell}
      messageinfo: [2×1 struct]
       attributes: {3×1 cell}
    attributeinfo: [3×1 struct]
         userdata: []

创建 j1939 通道

使用函数创建可用于发送和接收信息的 j1939 通道。

txch = j1939channel(db, "mathworks", "virtual 1", 1)

txch = 
  channel with properties:
   device information:
   -------------------
                  devicevendor: 'mathworks'
                        device: 'virtual 1'
            devicechannelindex: 1
            deviceserialnumber: 0
   data details:
   -------------
      parametergroupsavailable: 0
       parametergroupsreceived: 0
    parametergroupstransmitted: 0
                filterpasslist: []
               filterblocklist: []
   channel information:
   --------------------
                       running: 0
                     busstatus: 'n/a'
          initializationaccess: 1
              initialtimestamp: [0×0 datetime]
                    silentmode: 0
               transceivername: 'n/a'
              transceiverstate: 'n/a'
                      busspeed: 500000
                           sjw: []
                         tseg1: []
                         tseg2: []
                  numofsamples: []
   other information:
   ------------------
                      userdata: []

rxch = j1939channel(db, "mathworks", "virtual 1", 2)

rxch = 
  channel with properties:
   device information:
   -------------------
                  devicevendor: 'mathworks'
                        device: 'virtual 1'
            devicechannelindex: 2
            deviceserialnumber: 0
   data details:
   -------------
      parametergroupsavailable: 0
       parametergroupsreceived: 0
    parametergroupstransmitted: 0
                filterpasslist: []
               filterblocklist: []
   channel information:
   --------------------
                       running: 0
                     busstatus: 'n/a'
          initializationaccess: 1
              initialtimestamp: [0×0 datetime]
                    silentmode: 0
               transceivername: 'n/a'
              transceiverstate: 'n/a'
                      busspeed: 500000
                           sjw: []
                         tseg1: []
                         tseg2: []
                  numofsamples: []
   other information:
   ------------------
                      userdata: []

创建 j1939 参数组

使用函数创建要在网络上发送的单帧参数组。

pgsingleframe = j1939parametergroup(db, "vehicledatasingle")

pgsingleframe = 
  parametergroup with properties:
   protocol data unit details:
   ---------------------------
                  name: 'vehicledatasingle'
                   pgn: 40192
              priority: 6
         pduformattype: 'peer-to-peer (type 1)'
         sourceaddress: 254
    destinationaddress: 254
   data details:
   -------------
             timestamp: 0
                  data: [255 255 255 255 255 255 255 255]
               signals: [1×1 struct]
   other information:
   ------------------
              userdata: []

设置传输详细信息和信号数据。

pgsingleframe.sourceaddress = 30;
pgsingleframe.destinationaddress = 50;
pgsingleframe.signals.vehiclesignal1 = 25;
pgsingleframe.signals.vehiclesignal2 = 1000;
pgsingleframe.signals

ans = struct with fields:
    vehiclesignal4: -1
    vehiclesignal3: -1
    vehiclesignal2: 1000
    vehiclesignal1: 25

使用相同的方法，创建一个多帧参数组，然后设置传输详细信息和信号数据。

pgmultiframe = j1939parametergroup(db, "vehicledatamulti")

pgmultiframe = 
  parametergroup with properties:
   protocol data unit details:
   ---------------------------
                  name: 'vehicledatamulti'
                   pgn: 51200
              priority: 6
         pduformattype: 'peer-to-peer (type 1)'
         sourceaddress: 254
    destinationaddress: 254
   data details:
   -------------
             timestamp: 0
                  data: [255 255 255 255 255 255 255 255 255 255 255 255]
               signals: [1×1 struct]
   other information:
   ------------------
              userdata: []

pgmultiframe.sourceaddress = 30;
pgmultiframe.destinationaddress = 255;
pgmultiframe.signals.vehiclesignal1 = 5;
pgmultiframe.signals.vehiclesignal2 = 650;
pgmultiframe.signals.vehiclesignal3 = 5000;
pgmultiframe.signals

ans = struct with fields:
    vehiclesignal6: -1
    vehiclesignal5: -1
    vehiclesignal4: -1
    vehiclesignal3: 5000
    vehiclesignal2: 650
    vehiclesignal1: 5

启动 j1939 通道

使用函数启动 j1939 通道进行传输和接收操作。

start(rxch);
start(txch);

发送 j1939 参数组

函数将参数组发送到网络上。j1939 通道通过其传输协议自动发送要求使用多帧报文传输的参数组。

transmit(txch, pgsingleframe)
transmit(txch, pgsingleframe)
transmit(txch, pgmultiframe)
transmit(txch, pgsingleframe)
transmit(txch, pgsingleframe)
pause(2);

接收参数组

函数从网络上进行报文传输的通道中检索信息。

pgrx = receive(rxch, inf)

pgrx=5×8 timetable
       time              name            pgn     priority        pduformattype        sourceaddress    destinationaddress                        data                          signals   
    ___________    _________________    _____    ________    _____________________    _____________    __________________    ____________________________________________    ____________
    0.13955 sec    vehicledatasingle    40192       6        peer-to-peer (type 1)         30                  50            {[              25 0 232 3 255 255 255 255]}    {1×1 struct}
    0.14347 sec    vehicledatasingle    40192       6        peer-to-peer (type 1)         30                  50            {[              25 0 232 3 255 255 255 255]}    {1×1 struct}
    0.59386 sec    vehicledatamulti     51200       6        peer-to-peer (type 1)         30                 255            {[5 0 138 2 136 19 255 255 255 255 255 255]}    {1×1 struct}
    0.76564 sec    vehicledatasingle    40192       6        peer-to-peer (type 1)         30                  50            {[              25 0 232 3 255 255 255 255]}    {1×1 struct}
    0.7702 sec     vehicledatasingle    40192       6        peer-to-peer (type 1)         30                  50            {[              25 0 232 3 255 255 255 255]}    {1×1 struct}

检查收到的参数组信号

查看单帧和多帧参数组实例接收的信号的详细信息。

pgrx.signals{1}

ans = struct with fields:
    vehiclesignal4: -1
    vehiclesignal3: -1
    vehiclesignal2: 1000
    vehiclesignal1: 25

pgrx.signals{3}

ans = struct with fields:
    vehiclesignal6: -1
    vehiclesignal5: -1
    vehiclesignal4: -1
    vehiclesignal3: 5000
    vehiclesignal2: 650
    vehiclesignal1: 5

访问信号值

函数可用于从参数组时间表中轻松提取和变换信号数据。

sigtt = j1939signaltimetable(pgrx)

sigtt = struct with fields:
     vehicledatamulti: [1×6 timetable]
    vehicledatasingle: [4×4 timetable]

sigtt.vehicledatasingle

ans=4×4 timetable
       time        vehiclesignal4    vehiclesignal3    vehiclesignal2    vehiclesignal1
    ___________    ______________    ______________    ______________    ______________
    0.13955 sec          -1                -1               1000               25      
    0.14347 sec          -1                -1               1000               25      
    0.76564 sec          -1                -1               1000               25      
    0.7702 sec           -1                -1               1000               25

sigtt.vehicledatamulti

ans=1×6 timetable
       time        vehiclesignal6    vehiclesignal5    vehiclesignal4    vehiclesignal3    vehiclesignal2    vehiclesignal1
    ___________    ______________    ______________    ______________    ______________    ______________    ______________
    0.59386 sec          -1                -1                -1               5000              650                5

停止 j1939 通道

要停止从网络接收数据，请使用函数停止 j1939 通道。

stop(rxch);
stop(txch);