{
  "name": "遥控包",
  "type": "pkt",
  "children": [
    {
      "name": "主导头",
      "code": "primaryHeader",
      "length": 48,
      "type": "combPkt",
      "children": [
        {
          "name": "包识别",
          "code": "packetIdentifier",
          "length": 16,
          "type": "combPkt",
          "children": [
            {
              "name": "包版本号",
              "code": "packetVersionNumber",
              "length": 3,
              "value": "{{packetVersionNumber}}",
              "type": "const"
            },
            {
              "name": "包类型",
              "code": "packetType",
              "length": 1,
              "value": "{{packetType}}",
              "type": "const"
            },
            {
              "name": "数据区头标志",
              "code": "dataFieldHeaderFlag",
              "length": 1,
              "value": "{{dataFieldHeaderFlag}}",
              "type": "const"
            },
            {
              "name": "应用过程标识符",
              "code": "apid",
              "length": 11,
              "value": "{{apid}}",
              "type": "const"
            }
          ]
        },
        {
          "name": "包序列控制",
          "code": "sequenceControl",
          "length": 16,
          "type": "combPkt",
          "children": [
            {
              "name": "序列标志",
              "code": "sequenceFlags",
              "length": 2,
              "value": "{{sequenceFlags}}",
              "type": "const"
            },
            {
              "name": "包序列计数",
              "code": "packetSequenceCount",
              "length": 14,
              "type": "pktSeqCnt",
              "value": "0"
            }
          ]
        },
        {
          "name": "包长",
          "code": "packetLength",
          "length": 16,
          "type": "length",
          "value": {
            "start": "secondaryHeader",
            "end": "data",
            "formula": "N-1"
          }
        }
      ]
    },
    {
      "name": "副导头",
      "code": "secondaryHeader",
      "length": 8,
      "type": "combPkt",
      "children": [
        {
          "name": "副导头标志",
          "code": "ccsdsSecondaryHeaderFlag",
          "length": 1,
          "value": "{{ccsdsSecondaryHeaderFlag}}",
          "type": "const"
        },
        {
          "name": "遥控包版本号",
          "code": "tcPktVersionNumber",
          "length": 3,
          "value": "{{tcPktVersionNumber}}",
          "type": "const"
        },
        {
          "name": "命令正确应答",
          "code": "acknowledgmentFlag",
          "length": 4,
          "type": "const",
          "value": "{{acknowledgmentFlag}}"
        },
        {
          "name": "服务类型",
          "code": "serviceType",
          "length": 8,
          "type": "const",
          "value": "{{serviceType}}"
        },
        {
          "name": "服务子类型",
          "code": "serviceSubtype",
          "length": 8,
          "type": "const",
          "value": "{{serviceSubtype}}"
        },
        {
          "name": "源地址",
          "code": "sourceAddr",
          "length": 8,
          "value": "{{sourceAddr}}",
          "type": "const"
        }
      ]
    },
    {
      "name": "应用数据区",
      "code": "data",
      "length": null,
      "type": "insUnitList",
      "children": []
    },
    {
      "name": "包差错控制域",
      "code": "pktCheckSum",
      "length": 16,
      "type": "checkSum",
      "value": {"start": "START", "end": "PREV", "type": "ISOSum"}
    }
  ],
  "subPkts": []
}