{
  "topic": "KNX DPT9 浮点解析",
  "origin": "本文原创合成数据，未采集真实设备",
  "cases": [
    {
      "case_id": "25度",
      "kind": "正例",
      "input": {
        "hex": "0C E2"
      },
      "expected": {
        "sign": 0,
        "exponent": 1,
        "mantissa": 1250,
        "value": 25.0,
        "quantum": 0.02
      }
    },
    {
      "case_id": "负5度",
      "kind": "正例",
      "input": {
        "hex": "86 0C"
      },
      "expected": {
        "sign": 1,
        "exponent": 0,
        "mantissa": -500,
        "value": -5.0,
        "quantum": 0.01
      }
    },
    {
      "case_id": "指数台阶",
      "kind": "正例",
      "input": {
        "hex": "10 01"
      },
      "expected": {
        "sign": 0,
        "exponent": 2,
        "mantissa": 1,
        "value": 0.04,
        "quantum": 0.04
      }
    },
    {
      "case_id": "长度错",
      "kind": "显式负例",
      "input": {
        "hex": "0C E2 00"
      },
      "expected_error": "DPT9必须两字节"
    }
  ]
}