本文属于机器翻译版本。若本译文内容与英语原文存在差异，则一律以英文原文为准。

本文属于机器翻译版本。若本译文内容与英语原文存在差异，则一律以英文原文为准。

诊断故障代码用例

以下用例假设该DTC_QUERY函数是在演示脚本中定义的。

定期获取

按配置的时间间隔获取 DTC 集合。

以下示例是一个为所有人定期获取信号的Vehicle.DTC_INFO广告系列，所有人 DTCs 都有状态掩码。 ECUs收集数据是有条件的Vehicle.DTC_INFO。

{
  "compression": "SNAPPY",
  "spoolingMode": "TO_DISK",
  "signalsToFetch": [
    {
      "fullyQualifiedName": "Vehicle.ECU1.DTC_INFO",
      "signalFetchConfig": {
        "timeBased": {
        // The FleetWise Edge Agent will query the UDS module for all DTCs every five seconds.
          "executionFrequencyMs": 5000
        }
      },
      "actions": [
      // Every five seconds, this action is called and its output is stored in the
      // signal history buffer of Vehicle.DTC_INFO
        "custom_function(\"DTC_QUERY\", -1, 2, -1)"
      ]
    }
  ],
  "signalsToCollect": [
    {
      "name": "Vehicle.ECU1.DTC_INFO"
    }
  ],
  "collectionScheme": {
    "conditionBasedCollectionScheme": {
      "conditionLanguageVersion": 1,
      // Whenever a new DTC is filled into the signal, the data is ingested.
      "expression": "!isNull($variable.`Vehicle.ECU1.DTC_INFO`)",
      "minimumTriggerIntervalMs": 1000,
      // Make sure that data is ingested only when there are new DTCs.
      "triggerMode": "RISING_EDGE"
    }
  },
  "dataDestinationConfigs": [
    {
      "s3Config": 
        {
          "bucketArn": "bucket-arn",
          "dataFormat": "PARQUET",
          "prefix": "campaign-name",
          "storageCompressionFormat": "GZIP"
        }
    }
  ]
}

条件驱动的获取

满足条件时获取 DTC 集合。例如，当 CAN 信号为时Vehicle.Ignition == 1，获取并上传 DTC 数据。

以下示例广告系列具有条件驱动的信号提取，Vehicle.ECU1.DTC_INFO用于检查 DTC (”) 是否处于待处理状态，ECU-1 的 RecordNumber 1 AAA123 为 RecordNumber 1。此活动采用基于时间的数据收集和上传。

{
  "compression": "SNAPPY",
  "spoolingMode": "TO_DISK",
  "signalsToFetch": [
    {
      "fullyQualifiedName": "Vehicle.ECU1.DTC_INFO",
      "signalFetchConfig": {
        "conditionBased": {
        // The action will only run when the ignition is on.
          "conditionExpression": "$variable.`Vehicle.Ignition` == 1",
          "triggerMode": "ALWAYS"
        }
      },
      // The UDS module is only requested for the specific ECU address and the specific DTC Number/Status.
      "actions": ["custom_function(\"DTC_QUERY\", 1, 2, 8, \"0xAAA123\")"]
    }
  ],
  "signalsToCollect": [
    {
      "name": "Vehicle.ECU1.DTC_INFO"
    },
    {
      "name": "Vehicle.Ignition"
    }
  ],
  "collectionScheme": {
    "timeBasedCollectionScheme": {
      "periodMs": 10000
    }
  },
  "dataDestinationConfigs": [
    {
      "s3Config": 
        {
          "bucketArn": "bucket-arn",
          "dataFormat": "PARQUET",
          "prefix": "campaign-name",
          "storageCompressionFormat": "GZIP"
        }
    }
  ]
}

按需获取

为舰队获取特定 DTC。

对于按需使用案例，您可以使用定期提取中定义的相同活动。通过使用 AWS 物联网 FleetWise 控制台在部署活动后不久暂停活动或运行以下 CLI 命令来实现按需效果。

aws iotfleetwise update-campaign \
    --name campaign-name \
    --action APPROVE

然后，在 DTC 数据到来后暂停活动。

aws iotfleetwise update-campaign \
    --name campaign-name \
    --action SUSPEND

您可以再次恢复活动以获取 DTC 数据。

aws iotfleetwise update-campaign \
    --name campaign-name \
    --action RESUME