# Code example

The example program EcMasterDemoDc demonstrates, in contrast to EcMasterDemo, how to programmatically configure DCM parameters and how the application can generate the DCM log.

### **DCM Configuration (optional)**

```cpp
/* initialize the master */
dwRes = ecatInitMaster(&oInitParms);

/* configure the master */
dwRes = ecatConfigureNetwork(eCnfType_Filename, (EC_T_BYTE*)"ENI.xml", (EC_T_DWORD)OsStrlen("ENI.xml"));

/* register client */
EC_T_REGISTERRESULTS oRegisterClientResults;
OsMemset(&oRegisterClientResults, 0, sizeof(EC_T_REGISTERRESULTS));
dwRes = ecatRegisterClient(EcMasterNotifyCallback, pAppContext, &oRegisterClientResults);

/* configure DC */
EC_T_DC_CONFIGURE oDcConfigure;
OsMemset(&oDcConfigure, 0, sizeof(EC_T_DC_CONFIGURE));
oDcConfigure.dwTimeout = ETHERCAT_DC_TIMEOUT;
dwRes = ecatDcConfigure(&oDcConfigure);

/* configure DCM Bus Shift */
EC_T_DCM_CONFIG oDcmConfig;
OsMemset(&oDcmConfig, 0, sizeof(EC_T_DCM_CONFIG));
oDcmConfig.eMode = eDcmMode_BusShift;
oDcmConfig.u.BusShift.nCtlSetVal = DCM_CONTROLLER_SETVAL_NANOSEC;
oDcmConfig.u.BusShift.bLogEnabled = EC_TRUE;
dwRes = ecatDcmConfigure(&oDcmConfig, 0 /* dwInSyncTimeout */);

/* set EtherCAT devices to OPERATIONAL state */
dwRes = ecatSetMasterState(ETHERCAT_STATE_CHANGE_TIMEOUT, eEcatState_OP);
```

#### SEE ALSO
[`emDcConfigure()`](dc_api.html.md#_CPPv413emDcConfigure10EC_T_DWORDPK17EC_T_DC_CONFIGURE)

#### SEE ALSO
[`emDcmConfigure()`](dcm_api.html.md#_CPPv414emDcmConfigure10EC_T_DWORDPK15EC_T_DCM_CONFIG10EC_T_DWORD)

### **DCM Log (optional)**

```cpp
do
{
    /* wait for next cycle (event from scheduler task) */
    /* ... */

    /* process all received frames (read new input values) */
    dwRes = ecatExecJob(eUsrJob_ProcessAllRxFrames, &oJobParms);

    /* ... */

    EC_T_CHAR* szDcmLog = EC_NULL;
    ecatDcmGetLog(&szDcmLog);
    if (EC_NULL != szDcmLog)
    {
        ((CAtEmLogging*)pEcLogContext)->LogDcm(szDcmLog);
    }

    /* ... */
} while (!pAppContext->bJobTaskShutdown);
```

#### SEE ALSO
[`emDcmGetLog()`](dcm_api.html.md#_CPPv411emDcmGetLog10EC_T_DWORDPP9EC_T_CHAR)