{
  "kind": "合成对照输入与本地模型/解析结果，非设备实测",
  "article": "https://qifudev.com/article/nmea-comma-crlf-coverage/",
  "tool": "https://qifudev.com/tools/nmea-checksum/",
  "model": "XOR只覆盖起始$或!之后、星号之前的ASCII正文",
  "inputs": {
    "sentence": "$GPGLL,4916.45,N,12311.12,W,225444,A,"
  },
  "outputs": {
    "checksum": "1D",
    "complete": "$GPGLL,4916.45,N,12311.12,W,225444,A,*1D",
    "status": "已生成校验"
  },
  "extra_checks": [],
  "warnings": [
    "仅核对异或校验，不验证定位状态、字段语义或设备真实性。"
  ],
  "limitation": "支持$或!起始和可选末尾CRLF，不验证字段语义、定位有效性或完整NMEA语句类型。",
  "source": {
    "label": "u-blox：接收机接口与NMEA格式",
    "url": "https://content.u-blox.com/sites/default/files/products/documents/u-blox8-M8_ReceiverDescrProtSpec_UBX-13003221.pdf"
  },
  "measured": {
    "device": null,
    "firmware": null,
    "instrument": null,
    "conditions": null,
    "raw_result": null,
    "verdict": null
  }
}