chore: modular monolith folder split (no behavior change)

app/slm/routers/dashboard.py

@@ -0,0 +1,328 @@
+"""
+SLM Dashboard Router
+
+Provides API endpoints for the Sound Level Meters dashboard page.
+"""
+
+from fastapi import APIRouter, Request, Depends, Query
+from fastapi.templating import Jinja2Templates
+from fastapi.responses import HTMLResponse
+from sqlalchemy.orm import Session
+from sqlalchemy import func
+from datetime import datetime, timedelta
+import httpx
+import logging
+import os
+
+from backend.database import get_db
+from backend.models import RosterUnit
+from backend.routers.roster_edit import sync_slm_to_slmm_cache
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter(prefix="/api/slm-dashboard", tags=["slm-dashboard"])
+templates = Jinja2Templates(directory="templates")
+
+# SLMM backend URL - configurable via environment variable
+SLMM_BASE_URL = os.getenv("SLMM_BASE_URL", "http://localhost:8100")
+
+
+@router.get("/stats", response_class=HTMLResponse)
+async def get_slm_stats(request: Request, db: Session = Depends(get_db)):
+    """
+    Get summary statistics for SLM dashboard.
+    Returns HTML partial with stat cards.
+    """
+    # Query all SLMs
+    all_slms = db.query(RosterUnit).filter_by(device_type="sound_level_meter").all()
+
+    # Count deployed vs benched
+    deployed_count = sum(1 for slm in all_slms if slm.deployed and not slm.retired)
+    benched_count = sum(1 for slm in all_slms if not slm.deployed and not slm.retired)
+    retired_count = sum(1 for slm in all_slms if slm.retired)
+
+    # Count recently active (checked in last hour)
+    one_hour_ago = datetime.utcnow() - timedelta(hours=1)
+    active_count = sum(1 for slm in all_slms
+                      if slm.slm_last_check and slm.slm_last_check > one_hour_ago)
+
+    return templates.TemplateResponse("partials/slm_stats.html", {
+        "request": request,
+        "total_count": len(all_slms),
+        "deployed_count": deployed_count,
+        "benched_count": benched_count,
+        "active_count": active_count,
+        "retired_count": retired_count
+    })
+
+
+@router.get("/units", response_class=HTMLResponse)
+async def get_slm_units(
+    request: Request,
+    db: Session = Depends(get_db),
+    search: str = Query(None)
+):
+    """
+    Get list of SLM units for the sidebar.
+    Returns HTML partial with unit cards.
+    """
+    query = db.query(RosterUnit).filter_by(device_type="sound_level_meter")
+
+    # Filter by search term if provided
+    if search:
+        search_term = f"%{search}%"
+        query = query.filter(
+            (RosterUnit.id.like(search_term)) |
+            (RosterUnit.slm_model.like(search_term)) |
+            (RosterUnit.address.like(search_term))
+        )
+
+    # Only show deployed units by default
+    units = query.filter_by(deployed=True, retired=False).order_by(RosterUnit.id).all()
+
+    return templates.TemplateResponse("partials/slm_unit_list.html", {
+        "request": request,
+        "units": units
+    })
+
+
+@router.get("/live-view/{unit_id}", response_class=HTMLResponse)
+async def get_live_view(request: Request, unit_id: str, db: Session = Depends(get_db)):
+    """
+    Get live view panel for a specific SLM unit.
+    Returns HTML partial with live metrics and chart.
+    """
+    # Get unit from database
+    unit = db.query(RosterUnit).filter_by(id=unit_id, device_type="sound_level_meter").first()
+
+    if not unit:
+        return templates.TemplateResponse("partials/slm_live_view_error.html", {
+            "request": request,
+            "error": f"Unit {unit_id} not found"
+        })
+
+    # Get modem information if assigned
+    modem = None
+    modem_ip = None
+    if unit.deployed_with_modem_id:
+        modem = db.query(RosterUnit).filter_by(id=unit.deployed_with_modem_id, device_type="modem").first()
+        if modem:
+            modem_ip = modem.ip_address
+        else:
+            logger.warning(f"SLM {unit_id} is assigned to modem {unit.deployed_with_modem_id} but modem not found")
+
+    # Fallback to direct slm_host if no modem assigned (backward compatibility)
+    if not modem_ip and unit.slm_host:
+        modem_ip = unit.slm_host
+        logger.info(f"Using legacy slm_host for {unit_id}: {modem_ip}")
+
+    # Try to get current status from SLMM
+    current_status = None
+    measurement_state = None
+    is_measuring = False
+
+    try:
+        async with httpx.AsyncClient(timeout=5.0) as client:
+            # Get measurement state
+            state_response = await client.get(
+                f"{SLMM_BASE_URL}/api/nl43/{unit_id}/measurement-state"
+            )
+            if state_response.status_code == 200:
+                state_data = state_response.json()
+                measurement_state = state_data.get("measurement_state", "Unknown")
+                is_measuring = state_data.get("is_measuring", False)
+
+            # Get live status
+            status_response = await client.get(
+                f"{SLMM_BASE_URL}/api/nl43/{unit_id}/live"
+            )
+            if status_response.status_code == 200:
+                status_data = status_response.json()
+                current_status = status_data.get("data", {})
+    except Exception as e:
+        logger.error(f"Failed to get status for {unit_id}: {e}")
+
+    return templates.TemplateResponse("partials/slm_live_view.html", {
+        "request": request,
+        "unit": unit,
+        "modem": modem,
+        "modem_ip": modem_ip,
+        "current_status": current_status,
+        "measurement_state": measurement_state,
+        "is_measuring": is_measuring
+    })
+
+
+@router.post("/control/{unit_id}/{action}")
+async def control_slm(unit_id: str, action: str):
+    """
+    Send control commands to SLM (start, stop, pause, resume, reset).
+    Proxies to SLMM backend.
+    """
+    valid_actions = ["start", "stop", "pause", "resume", "reset"]
+
+    if action not in valid_actions:
+        return {"status": "error", "detail": f"Invalid action. Must be one of: {valid_actions}"}
+
+    try:
+        async with httpx.AsyncClient(timeout=10.0) as client:
+            response = await client.post(
+                f"{SLMM_BASE_URL}/api/nl43/{unit_id}/{action}"
+            )
+
+            if response.status_code == 200:
+                return response.json()
+            else:
+                return {
+                    "status": "error",
+                    "detail": f"SLMM returned status {response.status_code}"
+                }
+    except Exception as e:
+        logger.error(f"Failed to control {unit_id}: {e}")
+        return {
+            "status": "error",
+            "detail": str(e)
+        }
+
+@router.get("/config/{unit_id}", response_class=HTMLResponse)
+async def get_slm_config(request: Request, unit_id: str, db: Session = Depends(get_db)):
+    """
+    Get configuration form for a specific SLM unit.
+    Returns HTML partial with configuration form.
+    """
+    unit = db.query(RosterUnit).filter_by(id=unit_id, device_type="sound_level_meter").first()
+
+    if not unit:
+        return HTMLResponse(
+            content=f'<div class="text-red-500">Unit {unit_id} not found</div>',
+            status_code=404
+        )
+
+    return templates.TemplateResponse("partials/slm_config_form.html", {
+        "request": request,
+        "unit": unit
+    })
+
+
+@router.post("/config/{unit_id}")
+async def save_slm_config(request: Request, unit_id: str, db: Session = Depends(get_db)):
+    """
+    Save SLM configuration.
+    Updates unit parameters in the database.
+    """
+    unit = db.query(RosterUnit).filter_by(id=unit_id, device_type="sound_level_meter").first()
+
+    if not unit:
+        return {"status": "error", "detail": f"Unit {unit_id} not found"}
+
+    try:
+        # Get form data
+        form_data = await request.form()
+
+        # Update SLM-specific fields
+        unit.slm_model = form_data.get("slm_model") or None
+        unit.slm_serial_number = form_data.get("slm_serial_number") or None
+        unit.slm_frequency_weighting = form_data.get("slm_frequency_weighting") or None
+        unit.slm_time_weighting = form_data.get("slm_time_weighting") or None
+        unit.slm_measurement_range = form_data.get("slm_measurement_range") or None
+
+        # Update network configuration
+        modem_id = form_data.get("deployed_with_modem_id")
+        unit.deployed_with_modem_id = modem_id if modem_id else None
+
+        # Always update TCP and FTP ports (used regardless of modem assignment)
+        unit.slm_tcp_port = int(form_data.get("slm_tcp_port")) if form_data.get("slm_tcp_port") else None
+        unit.slm_ftp_port = int(form_data.get("slm_ftp_port")) if form_data.get("slm_ftp_port") else None
+
+        # Only update direct IP if no modem is assigned
+        if not modem_id:
+            unit.slm_host = form_data.get("slm_host") or None
+        else:
+            # Clear legacy direct IP field when modem is assigned
+            unit.slm_host = None
+
+        db.commit()
+        logger.info(f"Updated configuration for SLM {unit_id}")
+
+        # Sync updated configuration to SLMM cache
+        logger.info(f"Syncing SLM {unit_id} config changes to SLMM cache...")
+        result = await sync_slm_to_slmm_cache(
+            unit_id=unit_id,
+            host=unit.slm_host,  # Use the updated host from Terra-View
+            tcp_port=unit.slm_tcp_port,
+            ftp_port=unit.slm_ftp_port,
+            deployed_with_modem_id=unit.deployed_with_modem_id,  # Resolve modem IP if assigned
+            db=db
+        )
+
+        if not result["success"]:
+            logger.warning(f"SLMM cache sync warning for {unit_id}: {result['message']}")
+            # Config still saved in Terra-View (source of truth)
+
+        return {"status": "success", "unit_id": unit_id}
+
+    except Exception as e:
+        db.rollback()
+        logger.error(f"Failed to save config for {unit_id}: {e}")
+        return {"status": "error", "detail": str(e)}
+
+
+@router.get("/test-modem/{modem_id}")
+async def test_modem_connection(modem_id: str, db: Session = Depends(get_db)):
+    """
+    Test modem connectivity with a simple ping/health check.
+    Returns response time and connection status.
+    """
+    import subprocess
+    import time
+
+    # Get modem from database
+    modem = db.query(RosterUnit).filter_by(id=modem_id, device_type="modem").first()
+
+    if not modem:
+        return {"status": "error", "detail": f"Modem {modem_id} not found"}
+
+    if not modem.ip_address:
+        return {"status": "error", "detail": f"Modem {modem_id} has no IP address configured"}
+
+    try:
+        # Ping the modem (1 packet, 2 second timeout)
+        start_time = time.time()
+        result = subprocess.run(
+            ["ping", "-c", "1", "-W", "2", modem.ip_address],
+            capture_output=True,
+            text=True,
+            timeout=3
+        )
+        response_time = int((time.time() - start_time) * 1000)  # Convert to milliseconds
+
+        if result.returncode == 0:
+            return {
+                "status": "success",
+                "modem_id": modem_id,
+                "ip_address": modem.ip_address,
+                "response_time": response_time,
+                "message": "Modem is responding to ping"
+            }
+        else:
+            return {
+                "status": "error",
+                "modem_id": modem_id,
+                "ip_address": modem.ip_address,
+                "detail": "Modem not responding to ping"
+            }
+
+    except subprocess.TimeoutExpired:
+        return {
+            "status": "error",
+            "modem_id": modem_id,
+            "ip_address": modem.ip_address,
+            "detail": "Ping timeout (> 2 seconds)"
+        }
+    except Exception as e:
+        logger.error(f"Failed to ping modem {modem_id}: {e}")
+        return {
+            "status": "error",
+            "modem_id": modem_id,
+            "detail": str(e)
+        }

app/slm/routers/nl43_proxy.py

@@ -0,0 +1,301 @@
+"""
+SLMM (Sound Level Meter Manager) Proxy Router
+
+Proxies requests from SFM to the standalone SLMM backend service.
+SLMM runs on port 8100 and handles NL43/NL53 sound level meter communication.
+"""
+
+from fastapi import APIRouter, HTTPException, Request, Response, WebSocket, WebSocketDisconnect
+from fastapi.responses import StreamingResponse
+import httpx
+import websockets
+import asyncio
+import logging
+import os
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter(prefix="/api/slmm", tags=["slmm"])
+
+# SLMM backend URL - configurable via environment variable
+SLMM_BASE_URL = os.getenv("SLMM_BASE_URL", "http://localhost:8100")
+# WebSocket URL derived from HTTP URL
+SLMM_WS_BASE_URL = SLMM_BASE_URL.replace("http://", "ws://").replace("https://", "wss://")
+
+
+@router.get("/health")
+async def check_slmm_health():
+    """
+    Check if the SLMM backend service is reachable and healthy.
+    """
+    try:
+        async with httpx.AsyncClient(timeout=5.0) as client:
+            response = await client.get(f"{SLMM_BASE_URL}/health")
+
+            if response.status_code == 200:
+                data = response.json()
+                return {
+                    "status": "ok",
+                    "slmm_status": "connected",
+                    "slmm_url": SLMM_BASE_URL,
+                    "slmm_version": data.get("version", "unknown"),
+                    "slmm_response": data
+                }
+            else:
+                return {
+                    "status": "degraded",
+                    "slmm_status": "error",
+                    "slmm_url": SLMM_BASE_URL,
+                    "detail": f"SLMM returned status {response.status_code}"
+                }
+
+    except httpx.ConnectError:
+        return {
+            "status": "error",
+            "slmm_status": "unreachable",
+            "slmm_url": SLMM_BASE_URL,
+            "detail": "Cannot connect to SLMM backend. Is it running?"
+        }
+    except Exception as e:
+        return {
+            "status": "error",
+            "slmm_status": "error",
+            "slmm_url": SLMM_BASE_URL,
+            "detail": str(e)
+        }
+
+
+# WebSocket routes MUST come before the catch-all route
+@router.websocket("/{unit_id}/stream")
+async def proxy_websocket_stream(websocket: WebSocket, unit_id: str):
+    """
+    Proxy WebSocket connections to SLMM's /stream endpoint.
+
+    This allows real-time streaming of measurement data from NL43 devices
+    through the SFM unified interface.
+    """
+    await websocket.accept()
+    logger.info(f"WebSocket connection accepted for SLMM unit {unit_id}")
+
+    # Build target WebSocket URL
+    target_ws_url = f"{SLMM_WS_BASE_URL}/api/nl43/{unit_id}/stream"
+    logger.info(f"Connecting to SLMM WebSocket: {target_ws_url}")
+
+    backend_ws = None
+
+    try:
+        # Connect to SLMM backend WebSocket
+        backend_ws = await websockets.connect(target_ws_url)
+        logger.info(f"Connected to SLMM backend WebSocket for {unit_id}")
+
+        # Create tasks for bidirectional communication
+        async def forward_to_backend():
+            """Forward messages from client to SLMM backend"""
+            try:
+                while True:
+                    data = await websocket.receive_text()
+                    await backend_ws.send(data)
+            except WebSocketDisconnect:
+                logger.info(f"Client WebSocket disconnected for {unit_id}")
+            except Exception as e:
+                logger.error(f"Error forwarding to backend: {e}")
+
+        async def forward_to_client():
+            """Forward messages from SLMM backend to client"""
+            try:
+                async for message in backend_ws:
+                    await websocket.send_text(message)
+            except websockets.exceptions.ConnectionClosed:
+                logger.info(f"Backend WebSocket closed for {unit_id}")
+            except Exception as e:
+                logger.error(f"Error forwarding to client: {e}")
+
+        # Run both forwarding tasks concurrently
+        await asyncio.gather(
+            forward_to_backend(),
+            forward_to_client(),
+            return_exceptions=True
+        )
+
+    except websockets.exceptions.WebSocketException as e:
+        logger.error(f"WebSocket error connecting to SLMM backend: {e}")
+        try:
+            await websocket.send_json({
+                "error": "Failed to connect to SLMM backend",
+                "detail": str(e)
+            })
+        except Exception:
+            pass
+    except Exception as e:
+        logger.error(f"Unexpected error in WebSocket proxy for {unit_id}: {e}")
+        try:
+            await websocket.send_json({
+                "error": "Internal server error",
+                "detail": str(e)
+            })
+        except Exception:
+            pass
+    finally:
+        # Clean up connections
+        if backend_ws:
+            try:
+                await backend_ws.close()
+            except Exception:
+                pass
+        try:
+            await websocket.close()
+        except Exception:
+            pass
+        logger.info(f"WebSocket proxy closed for {unit_id}")
+
+
+@router.websocket("/{unit_id}/live")
+async def proxy_websocket_live(websocket: WebSocket, unit_id: str):
+    """
+    Proxy WebSocket connections to SLMM's /live endpoint.
+
+    Alternative WebSocket endpoint that may be used by some frontend components.
+    """
+    await websocket.accept()
+    logger.info(f"WebSocket connection accepted for SLMM unit {unit_id} (live endpoint)")
+
+    # Build target WebSocket URL - try /stream endpoint as SLMM uses that for WebSocket
+    target_ws_url = f"{SLMM_WS_BASE_URL}/api/nl43/{unit_id}/stream"
+    logger.info(f"Connecting to SLMM WebSocket: {target_ws_url}")
+
+    backend_ws = None
+
+    try:
+        # Connect to SLMM backend WebSocket
+        backend_ws = await websockets.connect(target_ws_url)
+        logger.info(f"Connected to SLMM backend WebSocket for {unit_id} (live endpoint)")
+
+        # Create tasks for bidirectional communication
+        async def forward_to_backend():
+            """Forward messages from client to SLMM backend"""
+            try:
+                while True:
+                    data = await websocket.receive_text()
+                    await backend_ws.send(data)
+            except WebSocketDisconnect:
+                logger.info(f"Client WebSocket disconnected for {unit_id} (live)")
+            except Exception as e:
+                logger.error(f"Error forwarding to backend (live): {e}")
+
+        async def forward_to_client():
+            """Forward messages from SLMM backend to client"""
+            try:
+                async for message in backend_ws:
+                    await websocket.send_text(message)
+            except websockets.exceptions.ConnectionClosed:
+                logger.info(f"Backend WebSocket closed for {unit_id} (live)")
+            except Exception as e:
+                logger.error(f"Error forwarding to client (live): {e}")
+
+        # Run both forwarding tasks concurrently
+        await asyncio.gather(
+            forward_to_backend(),
+            forward_to_client(),
+            return_exceptions=True
+        )
+
+    except websockets.exceptions.WebSocketException as e:
+        logger.error(f"WebSocket error connecting to SLMM backend (live): {e}")
+        try:
+            await websocket.send_json({
+                "error": "Failed to connect to SLMM backend",
+                "detail": str(e)
+            })
+        except Exception:
+            pass
+    except Exception as e:
+        logger.error(f"Unexpected error in WebSocket proxy for {unit_id} (live): {e}")
+        try:
+            await websocket.send_json({
+                "error": "Internal server error",
+                "detail": str(e)
+            })
+        except Exception:
+            pass
+    finally:
+        # Clean up connections
+        if backend_ws:
+            try:
+                await backend_ws.close()
+            except Exception:
+                pass
+        try:
+            await websocket.close()
+        except Exception:
+            pass
+        logger.info(f"WebSocket proxy closed for {unit_id} (live)")
+
+
+# HTTP catch-all route MUST come after specific routes (including WebSocket routes)
+@router.api_route("/{path:path}", methods=["GET", "POST", "PUT", "DELETE", "PATCH"])
+async def proxy_to_slmm(path: str, request: Request):
+    """
+    Proxy all requests to the SLMM backend service.
+
+    This allows SFM to act as a unified frontend for all device types,
+    while SLMM remains a standalone backend service.
+    """
+    # Build target URL
+    target_url = f"{SLMM_BASE_URL}/api/nl43/{path}"
+
+    # Get query parameters
+    query_params = dict(request.query_params)
+
+    # Get request body if present
+    body = None
+    if request.method in ["POST", "PUT", "PATCH"]:
+        try:
+            body = await request.body()
+        except Exception as e:
+            logger.error(f"Failed to read request body: {e}")
+            body = None
+
+    # Get headers (exclude host and other proxy-specific headers)
+    headers = dict(request.headers)
+    headers_to_exclude = ["host", "content-length", "transfer-encoding", "connection"]
+    proxy_headers = {k: v for k, v in headers.items() if k.lower() not in headers_to_exclude}
+
+    logger.info(f"Proxying {request.method} request to SLMM: {target_url}")
+
+    try:
+        async with httpx.AsyncClient(timeout=30.0) as client:
+            # Forward the request to SLMM
+            response = await client.request(
+                method=request.method,
+                url=target_url,
+                params=query_params,
+                headers=proxy_headers,
+                content=body
+            )
+
+            # Return the response from SLMM
+            return Response(
+                content=response.content,
+                status_code=response.status_code,
+                headers=dict(response.headers),
+                media_type=response.headers.get("content-type")
+            )
+
+    except httpx.ConnectError:
+        logger.error(f"Failed to connect to SLMM backend at {SLMM_BASE_URL}")
+        raise HTTPException(
+            status_code=503,
+            detail=f"SLMM backend service unavailable. Is SLMM running on {SLMM_BASE_URL}?"
+        )
+    except httpx.TimeoutException:
+        logger.error(f"Timeout connecting to SLMM backend at {SLMM_BASE_URL}")
+        raise HTTPException(
+            status_code=504,
+            detail="SLMM backend timeout"
+        )
+    except Exception as e:
+        logger.error(f"Error proxying to SLMM: {e}")
+        raise HTTPException(
+            status_code=500,
+            detail=f"Failed to proxy request to SLMM: {str(e)}"
+        )

app/slm/routers/ui.py

@@ -0,0 +1,123 @@
+"""
+Sound Level Meter UI Router
+
+Provides endpoints for SLM dashboard cards, detail pages, and real-time data.
+"""
+
+from fastapi import APIRouter, Depends, HTTPException, Request
+from fastapi.responses import HTMLResponse
+from fastapi.templating import Jinja2Templates
+from sqlalchemy.orm import Session
+from datetime import datetime
+import httpx
+import logging
+import os
+
+from backend.database import get_db
+from backend.models import RosterUnit
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter(prefix="/slm", tags=["slm-ui"])
+templates = Jinja2Templates(directory="templates")
+
+SLMM_BASE_URL = os.getenv("SLMM_BASE_URL", "http://172.19.0.1:8100")
+
+
+@router.get("/{unit_id}", response_class=HTMLResponse)
+async def slm_detail_page(request: Request, unit_id: str, db: Session = Depends(get_db)):
+    """Sound level meter detail page with controls."""
+
+    # Get roster unit
+    unit = db.query(RosterUnit).filter_by(id=unit_id).first()
+    if not unit or unit.device_type != "sound_level_meter":
+        raise HTTPException(status_code=404, detail="Sound level meter not found")
+
+    return templates.TemplateResponse("slm_detail.html", {
+        "request": request,
+        "unit": unit,
+        "unit_id": unit_id
+    })
+
+
+@router.get("/api/{unit_id}/summary")
+async def get_slm_summary(unit_id: str, db: Session = Depends(get_db)):
+    """Get SLM summary data for dashboard card."""
+
+    # Get roster unit
+    unit = db.query(RosterUnit).filter_by(id=unit_id).first()
+    if not unit or unit.device_type != "sound_level_meter":
+        raise HTTPException(status_code=404, detail="Sound level meter not found")
+
+    # Try to get live status from SLMM
+    status_data = None
+    try:
+        async with httpx.AsyncClient(timeout=3.0) as client:
+            response = await client.get(f"{SLMM_BASE_URL}/api/nl43/{unit_id}/status")
+            if response.status_code == 200:
+                status_data = response.json().get("data")
+    except Exception as e:
+        logger.warning(f"Failed to get SLM status for {unit_id}: {e}")
+
+    return {
+        "unit_id": unit_id,
+        "device_type": "sound_level_meter",
+        "deployed": unit.deployed,
+        "model": unit.slm_model or "NL-43",
+        "location": unit.address or unit.location,
+        "coordinates": unit.coordinates,
+        "note": unit.note,
+        "status": status_data,
+        "last_check": unit.slm_last_check.isoformat() if unit.slm_last_check else None,
+    }
+
+
+@router.get("/partials/{unit_id}/card", response_class=HTMLResponse)
+async def slm_dashboard_card(request: Request, unit_id: str, db: Session = Depends(get_db)):
+    """Render SLM dashboard card partial."""
+
+    summary = await get_slm_summary(unit_id, db)
+
+    return templates.TemplateResponse("partials/slm_card.html", {
+        "request": request,
+        "slm": summary
+    })
+
+
+@router.get("/partials/{unit_id}/controls", response_class=HTMLResponse)
+async def slm_controls_partial(request: Request, unit_id: str, db: Session = Depends(get_db)):
+    """Render SLM control panel partial."""
+
+    unit = db.query(RosterUnit).filter_by(id=unit_id).first()
+    if not unit or unit.device_type != "sound_level_meter":
+        raise HTTPException(status_code=404, detail="Sound level meter not found")
+
+    # Get current status from SLMM
+    measurement_state = None
+    battery_level = None
+    try:
+        async with httpx.AsyncClient(timeout=3.0) as client:
+            # Get measurement state
+            state_response = await client.get(
+                f"{SLMM_BASE_URL}/api/nl43/{unit_id}/measurement-state"
+            )
+            if state_response.status_code == 200:
+                measurement_state = state_response.json().get("measurement_state")
+
+            # Get battery level
+            battery_response = await client.get(
+                f"{SLMM_BASE_URL}/api/nl43/{unit_id}/battery"
+            )
+            if battery_response.status_code == 200:
+                battery_level = battery_response.json().get("battery_level")
+    except Exception as e:
+        logger.warning(f"Failed to get SLM control data for {unit_id}: {e}")
+
+    return templates.TemplateResponse("partials/slm_controls.html", {
+        "request": request,
+        "unit_id": unit_id,
+        "unit": unit,
+        "measurement_state": measurement_state,
+        "battery_level": battery_level,
+        "is_measuring": measurement_state == "Start"
+    })