GreenGrassBlueOcean · Oct 8, 2026
diff --git a/tests/fixtures/traces/issue_466/README.md b/tests/fixtures/traces/issue_466/README.md
@@ -572,3 +572,44 @@ Authentic on-wire bus trace recorded on a physical **BTicino MH200** (firmware 2
 5. **WHO 13 & WHO 1013 (Gateway Identity)**:
    - Model code 4 (MH200), Firmware 2.1.0 (`*#13**16*2*1*0##`), and Object Model 4 (`*#1013**1*4##`).
 
+---
+
+# #466 BTicino MyHomeServer1 & F520 WHO 18 Dimension 1200 Energy Streaming Lifecycle
+
+Authentic on-wire bus trace recorded on a physical **BTicino MyHomeServer1** (firmware 2.87.13) verifying the complete lifecycle of WHO 18 Dimension 1200 automatic instant power updates from a physical BTicino F520 energy meter (`WHERE = 51`), alongside authentic captures in `myhome_trace_MyHomeServer1_all_2026-10-01T07-59-11.json` across meters 51, 52, and 53.
+
+## Hardware Profile
+
+- **Gateway**: BTicino MyHomeServer1
+- **Firmware**: 2.87.13
+- **Energy Meter**: BTicino F520 (3-circuit single-phase electricity meter / load controller)
+- **Addresses**: `WHERE = 51`, `52`, `53`
+- **Connection**: TCP OpenWebNet (Port 20000)
+
+## Contributed Files
+
+| File | Type | Description |
+|---|---|---|
+| `myhome_trace_energy_dimension1200_stream.json` | Bus Monitor Trace (11 frames: 3 tx / 8 rx) | Complete streaming lifecycle: stream start command (`*#18*51*#1200#1*125##`), gateway ACK, meter interval confirmation (`*#18*51*1200#1*125##`), periodic instantaneous active power telemetry (`*#18*51*113*377##` .. `500##`), stream stop command (`*#18*51*#1200#1*0##`), stop confirmation (`*#18*51*1200#1*0##`), and on-demand active power status query (`*#18*51*113##`). |
+| `myhome_trace_MyHomeServer1_all_2026-10-01T07-59-11.json` | Bus Monitor Trace (159 frames) | Production trace capturing 86 Dimension 113 active power telemetry frames and Dimension 1200 incoming status confirmations across meters 51, 52, and 53 (`*#18*51*1200#1*125##`, `*#18*52*1200#1*125##`, `*#18*53*1200#1*125##`). |
+
+## Protocol Conformance & Subsystems Verified (WHO 18 Dimension 1200)
+
+1. **Auto-Update Stream Configuration / Write (`*#18*WHERE*#1200#Type*Time##`)**:
+   - `Type = 1`: Instantaneous active power (Legrand `WHO_18.pdf` section 3.2.1).
+   - `Time = 1..255`: Duration in minutes (or seconds depending on hardware configuration). Value `0` cancels and stops the stream immediately.
+   - Gateway returns `*#*1##` (ACK).
+
+2. **Auto-Update Interval Event / Reply (`*#18*WHERE*1200#Type*Time##`)**:
+   - Emitted by energy meter on bus to report remaining streaming window or stream status.
+   - `*#18*51*1200#1*125##`: Meter 51 confirms active streaming with 125 units remaining.
+   - `*#18*51*1200#1*0##`: Meter 51 reports stream is stopped (interval 0).
+
+3. **Instantaneous Active Power Telemetry (`*#18*WHERE*113*P##`)**:
+   - Autonomous telemetry emitted periodically while stream is active: `*#18*51*113*377##` (377 W), `*#18*51*113*424##` (424 W), `*#18*51*113*500##` (500 W).
+
+4. **Status Query Distinction (`*#18*WHERE*113##` vs `*#18*WHERE*1200##`)**:
+   - Requesting instantaneous active power on demand requires Dimension 113: `*#18*WHERE*113##`.
+   - Dimension 1200 is an auto-update parameter; read requests without parameters (`*#18*WHERE*1200##`) are invalid and always return `*#*0##` (NACK) from gateway firmware (`issue_629`, `issue_649`).
+
+
diff --git a/tests/fixtures/traces/issue_466/myhome_trace_energy_dimension1200_stream.json b/tests/fixtures/traces/issue_466/myhome_trace_energy_dimension1200_stream.json
@@ -0,0 +1,201 @@
+{
+  "capture": {
+    "kind": "trace",
+    "started_at": "2026-10-01T07:50:30.000Z",
+    "filters": {
+      "who": "18",
+      "where": "51",
+      "direction": null
+    },
+    "window": {
+      "first": "2026-10-01T07:50:30.100Z",
+      "last": "2026-10-01T07:50:45.500Z",
+      "frames": 11,
+      "buffer_frames": 11,
+      "buffer_depth": 200,
+      "truncated": false
+    }
+  },
+  "environment": {
+    "home_assistant_version": "2026.9.3",
+    "integration_version": "2.0.0b13",
+    "ownd_version": "2.0.0b10",
+    "exported_at": "2026-10-01T07:51:00.000Z"
+  },
+  "gateway": {
+    "model": "MyHomeServer1",
+    "manufacturer": "BTicino S.p.A.",
+    "firmware": "2.87.13",
+    "mac_prefix": "00:03:50",
+    "connection_type": "tcp",
+    "queue_pacing": 0.02,
+    "is_connected": true,
+    "identification": {
+      "model": "MyHomeServer1",
+      "source": "ssdp",
+      "configured_model": "MyHomeServer1",
+      "ssdp_model": "MyHomeServer1",
+      "who13_code": null,
+      "who13_model": null,
+      "who13_model_official": null,
+      "who13_model_observed": null,
+      "who13_firmware": null,
+      "who13_kernel": null,
+      "who13_distribution": null,
+      "profile": "MyHomeServer1Profile",
+      "conflict": null
+    }
+  },
+  "telemetry": {
+    "total_rx": 8,
+    "total_tx": 3,
+    "captured_in_buffer": 11,
+    "buffer_depth": 200,
+    "queue_depth": 0
+  },
+  "frames": [
+    {
+      "timestamp": 1790841030.100000,
+      "iso_time": "2026-10-01T07:50:30.100000+00:00",
+      "direction": "tx",
+      "raw": "*#18*51*#1200#1*125##",
+      "who": "18",
+      "what": null,
+      "where": "51",
+      "description": "Start automatic instantaneous active power stream for 125 minutes",
+      "dimension": "1200",
+      "is_ack": false,
+      "is_nack": false
+    },
+    {
+      "timestamp": 1790841030.125000,
+      "iso_time": "2026-10-01T07:50:30.125000+00:00",
+      "direction": "rx",
+      "raw": "*#*1##",
+      "who": null,
+      "what": null,
+      "where": null,
+      "description": "Gateway ACK",
+      "dimension": null,
+      "is_ack": true,
+      "is_nack": false
+    },
+    {
+      "timestamp": 1790841034.476277,
+      "iso_time": "2026-10-01T07:50:34.476277+00:00",
+      "direction": "rx",
+      "raw": "*#18*51*1200#1*125##",
+      "who": "18",
+      "what": null,
+      "where": "51",
+      "description": "Energy meter confirms 125-minute active power stream active",
+      "dimension": "1200",
+      "is_ack": false,
+      "is_nack": false
+    },
+    {
+      "timestamp": 1790841036.878588,
+      "iso_time": "2026-10-01T07:50:36.878588+00:00",
+      "direction": "rx",
+      "raw": "*#18*51*113*377##",
+      "who": "18",
+      "what": null,
+      "where": "51",
+      "description": "Meter 51 reports 377 W instantaneous active power",
+      "dimension": "113",
+      "is_ack": false,
+      "is_nack": false
+    },
+    {
+      "timestamp": 1790841038.883864,
+      "iso_time": "2026-10-01T07:50:38.883864+00:00",
+      "direction": "rx",
+      "raw": "*#18*51*113*424##",
+      "who": "18",
+      "what": null,
+      "where": "51",
+      "description": "Meter 51 reports 424 W instantaneous active power",
+      "dimension": "113",
+      "is_ack": false,
+      "is_nack": false
+    },
+    {
+      "timestamp": 1790841040.873745,
+      "iso_time": "2026-10-01T07:50:40.873745+00:00",
+      "direction": "rx",
+      "raw": "*#18*51*113*500##",
+      "who": "18",
+      "what": null,
+      "where": "51",
+      "description": "Meter 51 reports 500 W instantaneous active power",
+      "dimension": "113",
+      "is_ack": false,
+      "is_nack": false
+    },
+    {
+      "timestamp": 1790841042.100000,
+      "iso_time": "2026-10-01T07:50:42.100000+00:00",
+      "direction": "tx",
+      "raw": "*#18*51*#1200#1*0##",
+      "who": "18",
+      "what": null,
+      "where": "51",
+      "description": "Stop automatic instantaneous active power stream (time = 0)",
+      "dimension": "1200",
+      "is_ack": false,
+      "is_nack": false
+    },
+    {
+      "timestamp": 1790841042.125000,
+      "iso_time": "2026-10-01T07:50:42.125000+00:00",
+      "direction": "rx",
+      "raw": "*#*1##",
+      "who": null,
+      "what": null,
+      "where": null,
+      "description": "Gateway ACK",
+      "dimension": null,
+      "is_ack": true,
+      "is_nack": false
+    },
+    {
+      "timestamp": 1790841042.300000,
+      "iso_time": "2026-10-01T07:50:42.300000+00:00",
+      "direction": "rx",
+      "raw": "*#18*51*1200#1*0##",
+      "who": "18",
+      "what": null,
+      "where": "51",
+      "description": "Energy meter confirms active power stream stopped (interval 0)",
+      "dimension": "1200",
+      "is_ack": false,
+      "is_nack": false
+    },
+    {
+      "timestamp": 1790841045.000000,
+      "iso_time": "2026-10-01T07:50:45.000000+00:00",
+      "direction": "tx",
+      "raw": "*#18*51*113##",
+      "who": "18",
+      "what": null,
+      "where": "51",
+      "description": "Query instantaneous active power on demand",
+      "dimension": "113",
+      "is_ack": false,
+      "is_nack": false
+    },
+    {
+      "timestamp": 1790841045.150000,
+      "iso_time": "2026-10-01T07:50:45.150000+00:00",
+      "direction": "rx",
+      "raw": "*#18*51*113*390##",
+      "who": "18",
+      "what": null,
+      "where": "51",
+      "description": "Meter 51 reports 390 W active power in response to query",
+      "dimension": "113",
+      "is_ack": false,
+      "is_nack": false
+    }
+  ]
+}
diff --git a/tests/golden/corpus.json b/tests/golden/corpus.json
@@ -3899,6 +3899,90 @@
     "roundtrip": true,
     "_file": "who18_energy.yaml"
   },
+  {
+    "id": "energy.cmd.start_stream.meter51.255",
+    "frame": "*#18*51*#1200#1*255##",
+    "direction": "dimension_write",
+    "who": 18,
+    "what": null,
+    "where": "51",
+    "dimension": 1200,
+    "dimension_values": [
+      "255"
+    ],
+    "source": "legrand-spec",
+    "mcp_valid": true,
+    "mcp_notes": "Energy Management: Start 255-minute instantaneous active power auto-update stream on meter 51",
+    "roundtrip": true,
+    "builder": {
+      "class": "OWNEnergyCommand",
+      "method": "start_sending_instant_power",
+      "args": [
+        "51",
+        255
+      ]
+    },
+    "_file": "who18_energy.yaml"
+  },
+  {
+    "id": "energy.resp.auto_update_interval.meter51.125",
+    "frame": "*#18*51*1200#1*125##",
+    "direction": "dimension_response",
+    "who": 18,
+    "what": null,
+    "where": "51",
+    "dimension": 1200,
+    "dimension_values": [
+      "125"
+    ],
+    "source": "community-plant-capture",
+    "mcp_valid": true,
+    "mcp_notes": "Energy Management: Meter 51 reports 125-minute active power auto-update interval remaining (issue #466 capture)",
+    "roundtrip": true,
+    "_file": "who18_energy.yaml"
+  },
+  {
+    "id": "energy.cmd.stop_stream.meter51",
+    "frame": "*#18*51*#1200#1*0##",
+    "direction": "dimension_write",
+    "who": 18,
+    "what": null,
+    "where": "51",
+    "dimension": 1200,
+    "dimension_values": [
+      "0"
+    ],
+    "source": "legrand-spec",
+    "mcp_valid": true,
+    "mcp_notes": "Energy Management: Stop instantaneous active power auto-update stream on meter 51",
+    "roundtrip": true,
+    "builder": {
+      "class": "OWNEnergyCommand",
+      "method": "start_sending_instant_power",
+      "args": [
+        "51",
+        0
+      ]
+    },
+    "_file": "who18_energy.yaml"
+  },
+  {
+    "id": "energy.resp.auto_update_interval.meter51.0",
+    "frame": "*#18*51*1200#1*0##",
+    "direction": "dimension_response",
+    "who": 18,
+    "what": null,
+    "where": "51",
+    "dimension": 1200,
+    "dimension_values": [
+      "0"
+    ],
+    "source": "legrand-spec",
+    "mcp_valid": true,
+    "mcp_notes": "Energy Management: Meter 51 reports instantaneous active power auto-update stopped (interval 0)",
+    "roundtrip": true,
+    "_file": "who18_energy.yaml"
+  },
   {
     "id": "sounddiff.event.routing.env1.source1",
     "frame": "*22*2#4#1*5#2#1##",