Add runtime UV protection toggle and treat near-zero sense as external power.

Per-pod NVS enable (default off) via UART/ESP-NOW/dashboard, and skip UV latch when LiPo ADC reads ~0 mV so USB/external supply still boots.

Co-authored-by: Cursor <cursoragent@cursor.com>

docs/DOCUMENTATION.md

@@ -429,16 +429,18 @@ Spannungen in Millivolt in Registry und `BATTERY_STATUS`-UART.
 
 ### Software-UV-Schutz (`battery_uv.c`)
 
-Aktivierbar mit `POWERPOD_BATTERY_UV_ENABLE` in `powerpod.h` (CMake-Override möglich).
+Aktivierbar mit `POWERPOD_BATTERY_UV_ENABLE` in `powerpod.h` (CMake-Override möglich). Runtime zusätzlich NVS `uv_en` (Default **aus**) — UART `BATTERY_UV` / Dashboard / ESP-NOW `ESPNOW_SET_BATTERY_UV`.
 
 | Zustand | ADC-Schwelle | Logik |
 |---------|--------------|-------|
-| UV | < 2300 mV | Ein gültiger Kanal reicht |
-| Geladen | ≥ 3000 mV | Alle gültigen Kanäle |
+| Extern / kein Pack | < 100 mV | Alle gültigen Kanäle → normaler Boot |
+| UV | 100…2299 mV | Ein gültiger Kanal reicht |
+| Geladen | ≥ 3000 mV | Alle nicht-absent gültigen Kanäle |
 
-- NVS-Key `uv_latch` in `pod_settings.c`
-- Boot: ADC früh, bei UV nur LED + ADC-Poll (kein ESP-NOW/WiFi/UART/I2C/Button)
-- Runtime: `battery_uv_poll()` im LiPo-Monitor (2 Samples Debounce)
+- NVS-Keys `uv_latch`, `uv_en` in `pod_settings.c`
+- Boot: ADC früh, bei UV nur LED + ADC-Poll (kein ESP-NOW/WiFi/UART/I2C/Button); übersprungen wenn `uv_en=0`
+- Runtime: `battery_uv_poll()` im LiPo-Monitor (2 Samples Debounce), gated by `uv_en`
+- UART `BATTERY_UV`: `client_id` / `all_clients`; Disable cleart Latch
 - LED-Anzeige: Mode `6` battery-low (`led_ring_show_battery_low`)
 
 ---
@@ -452,6 +454,7 @@ Aktivierbar mit `POWERPOD_BATTERY_UV_ENABLE` in `powerpod.h` (CMake-Override mö
 | `accel_dz` | Accel-Deadzone LSB |
 | `tap_cfg` | BMA456 Multitap-Config (Blob) |
 | `uv_latch` | Software-UV-Zustand (`1` = Energiesparmodus) |
+| `uv_en` | Runtime-Enable UV-Schutz (`0`/`1`, fehlend = aus) |
 
 Gespeichert bei lokalem Set (UART `client_id=0`, ESP-NOW auf Slave). Geladen nach `init_bma456()`.
 

goTool/README.md

@@ -38,6 +38,7 @@ go run . -port /dev/ttyUSB0 clients
 | `find-me` | 22 | Locate pod (`-client 0` master, `>0` slave via ESP-NOW) |
 | `restart` | 23 | Reboot master or slave (`-client 0` / `>0`) |
 | `log-level` | `0x1f` | Get/set master ESP-IDF log level for tag `"*"` (`-set`, `-level` 0–5); output on UART0 debug, not host UART |
+| `battery-uv` | `0x24` | Get/set software LiPo UV protection (`-set -enable`/`-enable=false`, `-client`, `-all`) |
 | `input-send-mode` | `0x23` | Get/set slave accel/tap ESP-NOW TX path (`-set -mode 0..3`, `-all` or `-client N`): best_effort/fast/wait/reliable |
 
 `clients` requires slaves to have responded to master discover broadcasts first.

goTool/api_battery_uv.go

@@ -0,0 +1,140 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+
+	"powerpod/gotool/pb"
+)
+
+type batteryUvAPIRequest struct {
+	Write      bool   `json:"write"`
+	Enabled    bool   `json:"enabled"`
+	ClientID   uint32 `json:"client_id"`
+	AllClients bool   `json:"all_clients"`
+	// SlavesOnly: with all_clients, push to ESP-NOW slaves only (master NVS unchanged).
+	SlavesOnly bool `json:"slaves_only"`
+}
+
+type batteryUvAPIResponse struct {
+	ClientID      uint32 `json:"client_id"`
+	Success       bool   `json:"success"`
+	Enabled       bool   `json:"enabled"`
+	Latched       bool   `json:"latched"`
+	SlavesUpdated uint32 `json:"slaves_updated"`
+	Error         string `json:"error,omitempty"`
+}
+
+func mountBatteryUvAPI(mux *http.ServeMux, link *managedSerial) {
+	mux.HandleFunc("/api/battery-uv", func(w http.ResponseWriter, r *http.Request) {
+		switch r.Method {
+		case http.MethodGet:
+			serveBatteryUvGet(w, r, link)
+		case http.MethodPost:
+			serveBatteryUvPost(w, r, link)
+		default:
+			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+		}
+	})
+}
+
+func serveBatteryUvGet(w http.ResponseWriter, r *http.Request, link *managedSerial) {
+	clientID, err := parseUintQuery(r, "client_id", 0)
+	if err != nil {
+		writeJSON(w, http.StatusBadRequest, batteryUvAPIResponse{Error: err.Error()})
+		return
+	}
+	resp, err := link.BatteryUv(&pb.BatteryUvRequest{
+		Write:    false,
+		ClientId: clientID,
+	})
+	if err != nil {
+		writeJSON(w, http.StatusServiceUnavailable, batteryUvAPIResponse{
+			ClientID: clientID,
+			Error:    err.Error(),
+		})
+		return
+	}
+	writeJSON(w, http.StatusOK, batteryUvAPIResponse{
+		ClientID:      resp.GetClientId(),
+		Success:       resp.GetSuccess(),
+		Enabled:       resp.GetEnabled(),
+		Latched:       resp.GetLatched(),
+		SlavesUpdated: resp.GetSlavesUpdated(),
+	})
+}
+
+func serveBatteryUvPost(w http.ResponseWriter, r *http.Request, link *managedSerial) {
+	var body batteryUvAPIRequest
+	if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
+		writeJSON(w, http.StatusBadRequest, batteryUvAPIResponse{Error: "invalid JSON"})
+		return
+	}
+	if body.AllClients && body.SlavesOnly {
+		updated, err := applyBatteryUvToSlaves(link, body.Enabled)
+		if err != nil {
+			writeJSON(w, http.StatusServiceUnavailable, batteryUvAPIResponse{
+				Enabled: body.Enabled,
+				Error:   err.Error(),
+			})
+			return
+		}
+		writeJSON(w, http.StatusOK, batteryUvAPIResponse{
+			Success:       updated > 0,
+			Enabled:       body.Enabled,
+			SlavesUpdated: updated,
+		})
+		return
+	}
+
+	resp, err := link.BatteryUv(&pb.BatteryUvRequest{
+		Write:      true,
+		Enabled:    body.Enabled,
+		ClientId:   body.ClientID,
+		AllClients: body.AllClients,
+	})
+	if err != nil {
+		writeJSON(w, http.StatusServiceUnavailable, batteryUvAPIResponse{
+			ClientID: body.ClientID,
+			Enabled:  body.Enabled,
+			Error:    err.Error(),
+		})
+		return
+	}
+	writeJSON(w, http.StatusOK, batteryUvAPIResponse{
+		ClientID:      resp.GetClientId(),
+		Success:       resp.GetSuccess(),
+		Enabled:       resp.GetEnabled(),
+		Latched:       resp.GetLatched(),
+		SlavesUpdated: resp.GetSlavesUpdated(),
+	})
+}
+
+func applyBatteryUvToSlaves(link *managedSerial, enabled bool) (uint32, error) {
+	clients, err := link.listClients()
+	if err != nil {
+		return 0, err
+	}
+	var updated uint32
+	for _, c := range clients {
+		resp, err := link.BatteryUv(&pb.BatteryUvRequest{
+			Write:    true,
+			Enabled:  enabled,
+			ClientId: c.GetId(),
+		})
+		if err != nil {
+			continue
+		}
+		if resp.GetSuccess() {
+			updated++
+		}
+	}
+	if len(clients) == 0 {
+		return 0, fmt.Errorf("no slaves registered")
+	}
+	if updated == 0 {
+		return 0, fmt.Errorf("UV protection not applied to any slave")
+	}
+	return updated, nil
+}

goTool/api_serve.go

@@ -105,6 +105,7 @@ func mountServeAPI(mux *http.ServeMux, link *managedSerial, hub *wsHub, streamCt
 	mountInputSendModeAPI(mux, link)
 	mountTapAPI(mux, link, hub, tapCtl)
 	mountTapConfigAPI(mux, link)
+	mountBatteryUvAPI(mux, link)
 	mountLedRingAPI(mux, link)
 	mountBatteryAPI(mux, link)
 	mux.HandleFunc("/api/deadzone", func(w http.ResponseWriter, r *http.Request) {

goTool/client_api.go

@@ -290,6 +290,44 @@ func (m *managedSerial) tapConfigExchange(poll bool, req *pb.TapConfigRequest) (
 	return r, nil
 }
 
+func (m *managedSerial) BatteryUv(req *pb.BatteryUvRequest) (*pb.BatteryUvResponse, error) {
+	return m.batteryUvExchange(false, req)
+}
+
+func (m *managedSerial) BatteryUvPoll(req *pb.BatteryUvRequest) (*pb.BatteryUvResponse, error) {
+	return m.batteryUvExchange(true, req)
+}
+
+func (m *managedSerial) batteryUvExchange(poll bool, req *pb.BatteryUvRequest) (*pb.BatteryUvResponse, error) {
+	msg := &pb.UartMessage{
+		Type:    pb.MessageType_BATTERY_UV,
+		Payload: &pb.UartMessage_BatteryUvRequest{BatteryUvRequest: req},
+	}
+	body, err := proto.Marshal(msg)
+	if err != nil {
+		return nil, fmt.Errorf("encode: %w", err)
+	}
+	payload := append([]byte{byte(pb.MessageType_BATTERY_UV)}, body...)
+	var respPayload []byte
+	if poll {
+		respPayload, err = m.exchangePayloadPoll(payload, "BATTERY_UV")
+	} else {
+		respPayload, err = m.exchangePayload(payload, "BATTERY_UV")
+	}
+	if err != nil {
+		return nil, err
+	}
+	var respMsg pb.UartMessage
+	if err := proto.Unmarshal(respPayload[1:], &respMsg); err != nil {
+		return nil, fmt.Errorf("decode: %w", err)
+	}
+	r := respMsg.GetBatteryUvResponse()
+	if r == nil {
+		return nil, fmt.Errorf("missing battery_uv_response")
+	}
+	return r, nil
+}
+
 func (m *managedSerial) accelDeadzoneExchange(poll bool, req *pb.AccelDeadzoneRequest) (*pb.AccelDeadzoneResponse, error) {
 	msg := &pb.UartMessage{
 		Type:    pb.MessageType_ACCEL_DEADZONE,
@@ -510,6 +548,33 @@ func (s *serialPort) tapConfig(req *pb.TapConfigRequest) (*pb.TapConfigResponse,
 	return r, nil
 }
 
+func (s *serialPort) batteryUv(req *pb.BatteryUvRequest) (*pb.BatteryUvResponse, error) {
+	msg := &pb.UartMessage{
+		Type: pb.MessageType_BATTERY_UV,
+		Payload: &pb.UartMessage_BatteryUvRequest{
+			BatteryUvRequest: req,
+		},
+	}
+	body, err := proto.Marshal(msg)
+	if err != nil {
+		return nil, fmt.Errorf("encode: %w", err)
+	}
+	payload := append([]byte{byte(pb.MessageType_BATTERY_UV)}, body...)
+	respPayload, err := s.exchangePayload(payload, "BATTERY_UV")
+	if err != nil {
+		return nil, err
+	}
+	var respMsg pb.UartMessage
+	if err := proto.Unmarshal(respPayload[1:], &respMsg); err != nil {
+		return nil, fmt.Errorf("decode: %w", err)
+	}
+	r := respMsg.GetBatteryUvResponse()
+	if r == nil {
+		return nil, fmt.Errorf("missing battery_uv_response")
+	}
+	return r, nil
+}
+
 func (s *serialPort) espnowUnicastTest(clientID, seq uint32) (*pb.EspNowUnicastTestResponse, error) {
 	req := &pb.EspNowUnicastTestRequest{ClientId: clientID, Seq: seq}
 	msg := &pb.UartMessage{
@@ -681,6 +746,10 @@ func (s *serialPort) TapConfig(req *pb.TapConfigRequest) (*pb.TapConfigResponse,
 	return s.tapConfig(req)
 }
 
+func (s *serialPort) BatteryUv(req *pb.BatteryUvRequest) (*pb.BatteryUvResponse, error) {
+	return s.batteryUv(req)
+}
+
 func (s *serialPort) EspnowUnicastTest(clientID, seq uint32) (*pb.EspNowUnicastTestResponse, error) {
 	return s.espnowUnicastTest(clientID, seq)
 }

goTool/cmd_battery_uv.go

@@ -0,0 +1,34 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+
+	"powerpod/gotool/pb"
+)
+
+func runBatteryUv(sp *serialPort, args []string) error {
+	fs := flag.NewFlagSet("battery-uv", flag.ExitOnError)
+	write := fs.Bool("set", false, "write UV protection enable (default: read)")
+	enabled := fs.Bool("enable", false, "enable software UV protection")
+	clientID := fs.Uint("client", 0, "client id (0=local master)")
+	all := fs.Bool("all", false, "apply to master + all registered slaves")
+	if err := fs.Parse(args); err != nil {
+		return err
+	}
+
+	r, err := sp.batteryUv(&pb.BatteryUvRequest{
+		Write:      *write,
+		Enabled:    *enabled,
+		ClientId:   uint32(*clientID),
+		AllClients: *all,
+	})
+	if err != nil {
+		return err
+	}
+
+	fmt.Printf("client_id=%d success=%v enabled=%v latched=%v slaves_updated=%d\n",
+		r.GetClientId(), r.GetSuccess(), r.GetEnabled(), r.GetLatched(),
+		r.GetSlavesUpdated())
+	return nil
+}

goTool/dashboard.go

@@ -20,6 +20,8 @@ type MasterView struct {
 	RunningPartition string          `json:"running_partition,omitempty"`
 	Deadzone         uint32          `json:"deadzone,omitempty"`
 	TapConfig        *TapConfigView  `json:"tap_config,omitempty"`
+	UvProtection     *bool           `json:"uv_protection,omitempty"`
+	UvLatched        bool            `json:"uv_latched,omitempty"`
 	Lipo1            lipoReadingJSON `json:"lipo1"`
 	Lipo2            lipoReadingJSON `json:"lipo2"`
 	BatteryAgeMs     uint32          `json:"battery_age_ms,omitempty"`
@@ -58,6 +60,7 @@ type ClientView struct {
 	TapNotifySingle bool            `json:"tap_notify_single"`
 	TapNotifyDouble bool            `json:"tap_notify_double"`
 	TapNotifyTriple bool            `json:"tap_notify_triple"`
+	UvProtection    bool            `json:"uv_protection"`
 	LastTap         string          `json:"last_tap,omitempty"`
 	LastTapAt       int64           `json:"last_tap_at,omitempty"`
 	Lipo1           lipoReadingJSON `json:"lipo1"`
@@ -700,6 +703,11 @@ func pollDashboard(link *managedSerial, portName string, last *DashboardState, s
 	if tc, err := readTapConfigPoll(link, 0); err == nil {
 		st.Master.TapConfig = tc
 	}
+	if uv, err := readBatteryUvPoll(link, 0); err == nil {
+		en := uv.GetEnabled()
+		st.Master.UvProtection = &en
+		st.Master.UvLatched = uv.GetLatched()
+	}
 
 	clients, err := link.listClientsPoll()
 	if err != nil {
@@ -726,6 +734,7 @@ func pollDashboard(link *managedSerial, portName string, last *DashboardState, s
 			TapNotifySingle: c.GetTapNotifySingle(),
 			TapNotifyDouble: c.GetTapNotifyDouble(),
 			TapNotifyTriple: c.GetTapNotifyTriple(),
+			UvProtection:    c.GetUvProtectionEnabled(),
 		}
 		st.Clients = append(st.Clients, cv)
 	}
@@ -928,6 +937,20 @@ func tapConfigViewFromPB(r *pb.TapConfigResponse) *TapConfigView {
 	}
 }
 
+func readBatteryUvPoll(link *managedSerial, clientID uint32) (*pb.BatteryUvResponse, error) {
+	r, err := link.BatteryUvPoll(&pb.BatteryUvRequest{
+		Write:    false,
+		ClientId: clientID,
+	})
+	if err != nil {
+		return nil, err
+	}
+	if !r.GetSuccess() {
+		return nil, fmt.Errorf("battery uv read failed for client %d", clientID)
+	}
+	return r, nil
+}
+
 func readTapConfigPoll(link *managedSerial, clientID uint32) (*TapConfigView, error) {
 	r, err := link.TapConfigPoll(&pb.TapConfigRequest{
 		Write:    false,

goTool/docs/API_REST.md

@@ -400,6 +400,31 @@ go run . -port /dev/ttyUSB0 log-level -set -level 3
 
 Dashboard: Master card → dropdown **ESP Log-Level** with **Lesen** / **Setzen**.
 
+### Battery UV protection
+
+Runtime enable for software LiPo under-voltage protection (NVS `uv_en` per pod). Disable also clears `uv_latch`. `all_clients` applies to master + every registered slave; `slaves_only` with `all_clients` skips the master.
+
+```http
+GET /api/battery-uv?client_id=0
+POST /api/battery-uv
+Content-Type: application/json
+{"write": true, "enabled": false, "client_id": 0}
+{"write": true, "enabled": false, "all_clients": true}
+{"write": true, "enabled": false, "all_clients": true, "slaves_only": true}
+```
+
+```json
+{"success": true, "client_id": 0, "enabled": false, "latched": false, "slaves_updated": 0}
+```
+
+```bash
+go run . -port /dev/ttyUSB0 battery-uv
+go run . -port /dev/ttyUSB0 battery-uv -set -enable=false -client 0
+go run . -port /dev/ttyUSB0 battery-uv -set -enable=false -all
+```
+
+Dashboard: Master **UV-Schutz** checkbox + **Alle an/aus**; per-slave **UV** column.
+
 ### Input send mode (slave accel/tap ESP-NOW TX path)
 
 Debug A/B for how slaves transmit `ACCEL_SAMPLE` / `TAP_EVENT`. Default on slaves is `best_effort` (0). Master remembers the last mode for GET; write pushes via ESP-NOW.
@@ -486,6 +511,7 @@ Same as external API:
 | Unicast test | `POST /api/unicast-test` |
 | Echo ping | `POST /api/echo-ping` (per-slave latency; UI shows Host ms + ESP ms) |
 | Master log level | `GET` / `POST /api/log-level` or CLI `log-level` |
+| UV protection | `GET` / `POST /api/battery-uv` or CLI `battery-uv` |
 | Input-Send mode | `GET` / `PUT /api/input-send-mode` or CLI `input-send-mode` |
 | Tap notify S/D/T | `PUT /api/clients/{id}/tap-notify` |
 | Tap receive (UI) | Live stream + tap notify; see WebSocket doc for external API |

goTool/main.go

@@ -35,6 +35,7 @@ func usage() {
 	fmt.Fprintf(os.Stderr, "  find-me       blink LED ring red/green/blue (3× each, full brightness)\n")
 	fmt.Fprintf(os.Stderr, "  restart       reboot master or slave (ESP-NOW)\n")
 	fmt.Fprintf(os.Stderr, "  log-level     get/set master ESP-IDF log level (global)\n")
+	fmt.Fprintf(os.Stderr, "  battery-uv    get/set software LiPo UV protection (per pod / all)\n")
 	fmt.Fprintf(os.Stderr, "  input-send-mode  get/set slave accel/tap ESP-NOW send path\n\n")
 	flag.PrintDefaults()
 }
@@ -138,6 +139,13 @@ func main() {
 				break
 			}
 			runErr = runTapConfig(sp, flag.Args()[1:])
+		case "battery-uv", "battery_uv":
+			sp, ok := h.(*serialPort)
+			if !ok {
+				runErr = fmt.Errorf("%s over BLE not wired yet; use -port", cmd)
+				break
+			}
+			runErr = runBatteryUv(sp, flag.Args()[1:])
 		case "tap-notify", "tap_notify":
 			sp, ok := h.(*serialPort)
 			if !ok {

goTool/webui/index.html

@@ -383,6 +383,11 @@
                 <dd class="col-7" x-text="formatLipo(state.master?.lipo1)"></dd>
                 <dt class="col-5 text-muted">LiPo 2</dt>
                 <dd class="col-7" x-text="formatLipo(state.master?.lipo2)"></dd>
+                <dt class="col-5 text-muted">UV-Schutz</dt>
+                <dd class="col-7">
+                  <span x-text="state.master?.uv_protection == null ? '—' : (state.master.uv_protection ? 'an' : 'aus')"></span>
+                  <span class="text-warning small ms-1" x-show="state.master?.uv_latched">· gelatcht</span>
+                </dd>
               </dl>
             </template>
             <template x-if="state.master && !state.master.ok">
@@ -512,6 +517,31 @@
                   Setzen
                 </button>
               </div>
+              <h6 class="text-secondary mb-2 mt-3">UV-Schutz (LiPo)</h6>
+              <div class="d-flex flex-wrap gap-2 align-items-center">
+                <label class="tap-toggle mb-0">
+                  <input type="checkbox"
+                         :checked="!!state.master?.uv_protection"
+                         @change="setBatteryUv(0, $event.target.checked)"
+                         :disabled="busy || !hostUp()">
+                  Master aktiv
+                </label>
+                <button type="button" class="btn btn-outline-secondary btn-sm"
+                        @click="setBatteryUvAll(true)"
+                        :disabled="busy || !hostUp()"
+                        title="UV-Schutz auf Master + alle Slaves einschalten">
+                  Alle an
+                </button>
+                <button type="button" class="btn btn-outline-warning btn-sm"
+                        @click="setBatteryUvAll(false)"
+                        :disabled="busy || !hostUp()"
+                        title="UV-Schutz auf Master + alle Slaves ausschalten (cleart Latch)">
+                  Alle aus
+                </button>
+              </div>
+              <p class="text-muted small mt-1 mb-0">
+                Runtime-NVS pro Pod. Im Energiesparmodus (gelatcht) kein Host-Zugriff.
+              </p>
               <p class="text-muted small mt-2 mb-0" x-show="!hostUp()">
                 Host nicht verbunden — Eingabe gesperrt.
               </p>
@@ -540,6 +570,12 @@
                       title="Master-Tap-Config an alle Slaves (ESP-NOW)">
                 Tap-Cfg alle
               </button>
+              <button type="button" class="btn btn-outline-warning btn-sm"
+                      @click="setBatteryUvSlavesOnly(false)"
+                      :disabled="busy || !hostUp() || !(state.clients || []).length"
+                      title="UV-Schutz nur auf allen Slaves ausschalten">
+                UV Slaves aus
+              </button>
               <button type="button" class="btn btn-outline-danger btn-sm"
                       @click="resetClientIdMap()"
                       :disabled="busy || !hostUp()"
@@ -611,6 +647,7 @@
                     <th>Tap-Cfg</th>
                     <th>Accel (LSB)</th>
                     <th>Akku</th>
+                    <th>UV</th>
                     <th>Accel</th>
                     <th>Tap-Notify</th>
                     <th>Tap</th>
@@ -619,7 +656,7 @@
                 </thead>
                 <tbody>
                   <template x-if="!(state.clients || []).length">
-                    <tr><td colspan="12" class="text-muted text-center py-4">No clients</td></tr>
+                    <tr><td colspan="13" class="text-muted text-center py-4">No clients</td></tr>
                   </template>
                   <template x-for="c in (state.clients || [])" :key="c.id + c.mac">
                     <tr>
@@ -648,6 +685,14 @@
                               :title="accelTitle(c)"></span>
                       </td>
                       <td class="small" x-text="formatLipoPair(c)" :title="lipoTitle(c)"></td>
+                      <td>
+                        <label class="tap-toggle mb-0" title="Software-UV-Schutz (NVS auf Slave)">
+                          <input type="checkbox"
+                                 :checked="!!c.uv_protection"
+                                 @change="setBatteryUv(c.id, $event.target.checked)"
+                                 :disabled="busy || !hostUp() || !c.available">
+                        </label>
+                      </td>
                       <td>
                         <button type="button"
                                 class="btn btn-sm"
@@ -1783,6 +1828,94 @@
             this.busy = false;
           }
         },
+        patchBatteryUv(clientId, enabled, latched) {
+          if (clientId === 0) {
+            const master = {
+              ...(this.state.master || {}),
+              uv_protection: !!enabled,
+              uv_latched: !!latched
+            };
+            this.state = { ...this.state, master };
+            return;
+          }
+          const clients = (this.state.clients || []).map((c) =>
+            c.id === clientId ? { ...c, uv_protection: !!enabled } : c);
+          this.state = { ...this.state, clients };
+        },
+        async setBatteryUv(clientId, enabled) {
+          this.busy = true;
+          try {
+            const r = await fetch('/api/battery-uv', {
+              method: 'POST',
+              headers: { 'Content-Type': 'application/json' },
+              body: JSON.stringify({ write: true, enabled: !!enabled, client_id: clientId })
+            });
+            const data = await r.json();
+            if (!r.ok || !data.success) {
+              this.flash(data.error || `UV-Schutz ${clientId === 0 ? 'Master' : 'Slave ' + clientId} fehlgeschlagen`, false);
+              return;
+            }
+            this.patchBatteryUv(clientId, data.enabled, data.latched);
+            const who = clientId === 0 ? 'Master' : `Slave ${clientId}`;
+            this.flash(`${who}: UV-Schutz ${data.enabled ? 'an' : 'aus'}`, true);
+          } catch (e) {
+            this.flash(String(e), false);
+          } finally {
+            this.busy = false;
+          }
+        },
+        async setBatteryUvAll(enabled) {
+          this.busy = true;
+          try {
+            const r = await fetch('/api/battery-uv', {
+              method: 'POST',
+              headers: { 'Content-Type': 'application/json' },
+              body: JSON.stringify({ write: true, enabled: !!enabled, all_clients: true })
+            });
+            const data = await r.json();
+            if (!r.ok || !data.success) {
+              this.flash(data.error || 'UV-Schutz für alle fehlgeschlagen', false);
+              return;
+            }
+            this.patchBatteryUv(0, data.enabled, data.latched);
+            for (const c of (this.state.clients || [])) {
+              this.patchBatteryUv(c.id, !!enabled, false);
+            }
+            this.flash(`UV-Schutz alle ${enabled ? 'an' : 'aus'} (${data.slaves_updated || 0} Slaves)`, true);
+          } catch (e) {
+            this.flash(String(e), false);
+          } finally {
+            this.busy = false;
+          }
+        },
+        async setBatteryUvSlavesOnly(enabled) {
+          this.busy = true;
+          try {
+            const r = await fetch('/api/battery-uv', {
+              method: 'POST',
+              headers: { 'Content-Type': 'application/json' },
+              body: JSON.stringify({
+                write: true,
+                enabled: !!enabled,
+                all_clients: true,
+                slaves_only: true
+              })
+            });
+            const data = await r.json();
+            if (!r.ok || !data.success) {
+              this.flash(data.error || 'UV-Schutz Slaves fehlgeschlagen', false);
+              return;
+            }
+            for (const c of (this.state.clients || [])) {
+              this.patchBatteryUv(c.id, !!enabled, false);
+            }
+            this.flash(`UV-Schutz Slaves ${enabled ? 'an' : 'aus'} (${data.slaves_updated || 0})`, true);
+          } catch (e) {
+            this.flash(String(e), false);
+          } finally {
+            this.busy = false;
+          }
+        },
         patchLiveStream(enabled) {
           let clients = this.state.clients || [];
           if (!enabled) {

main/CMakeLists.txt

@@ -34,6 +34,7 @@ idf_component_register(
   "pod_reboot.c"
   "cmd/cmd_led_ring.c"
   "cmd/cmd_battery.c"
+  "cmd/cmd_battery_uv.c"
   "cmd/cmd_set_log_level.c"
   "cmd/cmd_ota.c"
   "cmd/cmd_ota_slave_progress.c"

main/README.md

@@ -121,6 +121,7 @@ Schema: `proto/esp_now_messages.proto`. Encode/decode: `esp_now_proto.c`. The ES
 | `ESPNOW_HEARTBEAT` | Slave → master | `EspNowSlavePresence` (same fields) |
 | `ESPNOW_SET_ACCEL_DEADZONE` | Master → slave | `EspNowAccelDeadzone` (`deadzone` LSB) |
 | `ESPNOW_SET_TAP_CONFIG` | Master → slave | `EspNowTapConfig` (multitap sens/timing/axis + enable S/D/T) |
+| `ESPNOW_SET_BATTERY_UV` | Master → slave | `EspNowBatteryUv` (runtime UV enable + clear latch when off) |
 | `ESPNOW_UNICAST_TEST` | Master → slave | `EspNowUnicastTest` (`seq`) |
 | `ESPNOW_FIND_ME` | Master → slave | `EspNowFindMe` (`client_id` filter) — LED locate sequence |
 | `ESPNOW_RESTART` | Master → slave | `EspNowRestart` (`client_id` filter) — reboot slave |
@@ -240,6 +241,7 @@ Host and master speak nanopb-encoded `UartMessage` inside UART frames (byte 0 =
 | 30 | `ESPNOW_ECHO_PING` | Implemented (`cmd/cmd_espnow_echo_ping.c`) — ESP-NOW timestamp echo (latency test) |
 | 31 | `SET_LOG_LEVEL` | Implemented (`cmd/cmd_set_log_level.c`) — get/set global `esp_log_level_set("*", …)` on master |
 | 32 | `TAP_CONFIG` | Implemented (`cmd/cmd_tap_config.c`) — get/set BMA456H multitap params (+ NVS) |
+| 36 | `BATTERY_UV` | Implemented (`cmd/cmd_battery_uv.c`) — get/set software UV enable (+ NVS / ESP-NOW) |
 
 Regenerate C code:
 
@@ -473,14 +475,17 @@ Read **cached** LiPo ADC values on the **master** (master local + one entry per
 
 ### Software UV protection (LiPo)
 
-When `POWERPOD_BATTERY_UV_ENABLE` is `1` (default in `powerpod.h`, disable via CMake), the firmware monitors ADC pin voltages on GPIO 1 and 11:
+When `POWERPOD_BATTERY_UV_ENABLE` is `1` (default in `powerpod.h`, disable via CMake), the firmware can monitor ADC pin voltages on GPIO 1 and 11. Runtime enable is NVS `uv_en` per pod (missing key → **disabled**); UART `BATTERY_UV` / dashboard toggles it on master and slaves.
 
 | Condition | ADC threshold | Action |
 |-----------|---------------|--------|
-| Under-voltage | any valid channel < **2300 mV** (3.0 V pack) | NVS latch `uv_latch`, restart into energy-save mode |
-| Charged | all valid channels ≥ **3000 mV** (4.0 V pack) | Clear latch, restart into normal boot |
+| External / absent | every valid channel < **100 mV** | Normal boot (no UV); clears latch if set |
+| Under-voltage | any valid channel in **100…2299 mV** | NVS latch `uv_latch`, restart into energy-save mode |
+| Charged | every non-absent valid channel ≥ **3000 mV** | Clear latch, restart into normal boot |
 
-**Energy-save boot:** LED mode `6` (first 4 LEDs red ~10 % for 5 s), then no WiFi/ESP-NOW, UART, I2C, BMA456, or button — only LiPo ADC polling every 30 s until charged.
+**Energy-save boot:** LED mode `6` (first 4 LEDs red ~10 % for 5 s), then no WiFi/ESP-NOW, UART, I2C, BMA456, or button — only LiPo ADC polling every 30 s until charged. Disabling UV while latched clears the latch (requires a reachable host — not while already in energy-save).
+
+**UART:** `BATTERY_UV` (`0x24`) — `client_id=0` master, `>0` one slave, `all_clients` master + all slaves. Disabling also clears `uv_latch`.
 
 **Test LED pattern from host:** `led-ring -mode battery-low` (works even when UV feature is disabled).
 
@@ -614,6 +619,7 @@ Target: ESP32-S3. Close serial monitor on the UART adapter port before running `
 | `pod_settings.c/h` | NVS persistence (accel deadzone, tap config, UV latch) |
 | `led_ring.c/h` | LED ring (digit display, progress bar) |
 | `cmd/cmd_led_ring.c` | UART `LED_RING` progress command |
+| `cmd/cmd_battery_uv.c` | UART `BATTERY_UV` — software UV enable + NVS / ESP-NOW |
 | `cmd/cmd_set_log_level.c` | UART `SET_LOG_LEVEL` — runtime ESP-IDF log level |
 | `proto/uart_messages.proto` | UART protocol schema |
 | `proto/esp_now_messages.proto` | ESP-NOW protocol schema |

main/battery_uv.c

@@ -19,15 +19,55 @@ static uint8_t s_charge_streak;
 
 bool battery_uv_is_latched(void) { return pod_settings_is_uv_latched(); }
 
+static bool channel_is_absent(uint32_t mv) {
+  return mv < BATTERY_UV_ABSENT_ADC_MV;
+}
+
+static bool channel_is_under(uint32_t mv) {
+  return !channel_is_absent(mv) && mv < BATTERY_UV_ADC_MV;
+}
+
+static void log_lipo_reading(const char *ctx, const board_lipo_reading_t *reading) {
+  if (reading == NULL) {
+    return;
+  }
+  ESP_LOGI(TAG,
+           "%s LIPO1 %s %lu mV  LIPO2 %s %lu mV", ctx,
+           reading->lipo1_valid ? "ok" : "n/a",
+           (unsigned long)reading->lipo1_mv, reading->lipo2_valid ? "ok" : "n/a",
+           (unsigned long)reading->lipo2_mv);
+}
+
+bool battery_uv_reading_is_external(const board_lipo_reading_t *reading) {
+  if (reading == NULL) {
+    return false;
+  }
+
+  bool any_valid = false;
+  if (reading->lipo1_valid) {
+    any_valid = true;
+    if (!channel_is_absent(reading->lipo1_mv)) {
+      return false;
+    }
+  }
+  if (reading->lipo2_valid) {
+    any_valid = true;
+    if (!channel_is_absent(reading->lipo2_mv)) {
+      return false;
+    }
+  }
+  return any_valid;
+}
+
 bool battery_uv_reading_is_under(const board_lipo_reading_t *reading) {
   if (reading == NULL) {
     return false;
   }
 
-  if (reading->lipo1_valid && reading->lipo1_mv < BATTERY_UV_ADC_MV) {
+  if (reading->lipo1_valid && channel_is_under(reading->lipo1_mv)) {
     return true;
   }
-  if (reading->lipo2_valid && reading->lipo2_mv < BATTERY_UV_ADC_MV) {
+  if (reading->lipo2_valid && channel_is_under(reading->lipo2_mv)) {
     return true;
   }
   return false;
@@ -38,25 +78,39 @@ bool battery_uv_reading_is_charged(const board_lipo_reading_t *reading) {
     return false;
   }
 
-  bool any_valid = false;
-  if (reading->lipo1_valid) {
-    any_valid = true;
+  bool any_pack = false;
+  if (reading->lipo1_valid && !channel_is_absent(reading->lipo1_mv)) {
+    any_pack = true;
     if (reading->lipo1_mv < BATTERY_CHARGE_ADC_MV) {
       return false;
     }
   }
-  if (reading->lipo2_valid) {
-    any_valid = true;
+  if (reading->lipo2_valid && !channel_is_absent(reading->lipo2_mv)) {
+    any_pack = true;
     if (reading->lipo2_mv < BATTERY_CHARGE_ADC_MV) {
       return false;
     }
   }
-  return any_valid;
+  return any_pack;
 }
 
 bool battery_uv_evaluate_boot(void) {
+  if (!pod_settings_is_uv_enabled()) {
+    ESP_LOGI(TAG, "UV protection disabled — normal boot");
+    return false;
+  }
+
   board_lipo_reading_t reading;
   board_input_read_lipo(&reading);
+  log_lipo_reading("boot check", &reading);
+
+  if (battery_uv_reading_is_external(&reading)) {
+    ESP_LOGI(TAG, "near-zero LiPo sense — external supply, normal boot");
+    if (pod_settings_is_uv_latched()) {
+      pod_settings_clear_uv_latched();
+    }
+    return false;
+  }
 
   if (pod_settings_is_uv_latched() && battery_uv_reading_is_charged(&reading)) {
     ESP_LOGI(TAG, "charged — clearing UV latch");
@@ -78,12 +132,19 @@ bool battery_uv_evaluate_boot(void) {
 }
 
 void battery_uv_poll(const board_lipo_reading_t *reading) {
-  if (reading == NULL || pod_settings_is_uv_latched()) {
+  if (reading == NULL || !pod_settings_is_uv_enabled() ||
+      pod_settings_is_uv_latched()) {
+    return;
+  }
+
+  if (battery_uv_reading_is_external(reading)) {
+    s_uv_streak = 0;
     return;
   }
 
   if (battery_uv_reading_is_under(reading)) {
     s_uv_streak++;
+    log_lipo_reading("under-voltage", reading);
     ESP_LOGW(TAG, "under-voltage sample %u/%u", (unsigned)s_uv_streak,
              (unsigned)UV_DEBOUNCE_SAMPLES);
     if (s_uv_streak >= UV_DEBOUNCE_SAMPLES) {
@@ -109,8 +170,13 @@ void battery_uv_run_mode(void) {
   while (1) {
     board_lipo_reading_t reading;
     board_input_read_lipo(&reading);
+    log_lipo_reading("energy-save", &reading);
 
-    if (battery_uv_reading_is_charged(&reading)) {
+    if (battery_uv_reading_is_external(&reading)) {
+      ESP_LOGI(TAG, "external supply — clearing UV latch and restarting");
+      pod_settings_clear_uv_latched();
+      pod_schedule_restart();
+    } else if (battery_uv_reading_is_charged(&reading)) {
       s_charge_streak++;
       ESP_LOGI(TAG, "charge sample %u/%u", (unsigned)s_charge_streak,
                (unsigned)UV_DEBOUNCE_SAMPLES);

main/battery_uv.h

@@ -11,10 +11,17 @@
 #define BATTERY_UV_ADC_MV 2300u
 /** ADC pin voltage (mV) at which charging is detected (4.0 V pack, rounded). */
 #define BATTERY_CHARGE_ADC_MV 3000u
+/**
+ * ADC readings below this are treated as no pack / external supply (not UV).
+ * Noise floor / open sense divider → near 0 mV.
+ */
+#define BATTERY_UV_ABSENT_ADC_MV 100u
 
 bool battery_uv_is_latched(void);
 bool battery_uv_reading_is_under(const board_lipo_reading_t *reading);
 bool battery_uv_reading_is_charged(const board_lipo_reading_t *reading);
+/** true when every valid channel is near 0 (externally powered / no LiPo). */
+bool battery_uv_reading_is_external(const board_lipo_reading_t *reading);
 
 /** true → enter UV energy-save path (does not return). */
 bool battery_uv_evaluate_boot(void);
@@ -38,6 +45,11 @@ static inline bool battery_uv_reading_is_charged(const board_lipo_reading_t *rea
   return false;
 }
 
+static inline bool battery_uv_reading_is_external(const board_lipo_reading_t *reading) {
+  (void)reading;
+  return false;
+}
+
 static inline bool battery_uv_evaluate_boot(void) { return false; }
 
 static inline void battery_uv_poll(const board_lipo_reading_t *reading) {

main/client_registry.c

@@ -143,6 +143,7 @@ static client_slot_t *alloc_slot(const uint8_t mac[CLIENT_MAC_LEN],
         static const bma456_tap_config_t k_tap_default = BMA456_TAP_CONFIG_DEFAULT;
         slot->info.tap_config = k_tap_default;
       }
+      slot->info.uv_protection_enabled = false;
       if (out_is_new != NULL) {
         *out_is_new = true;
       }
@@ -435,6 +436,41 @@ size_t client_registry_set_tap_config_all(const bma456_tap_config_t *cfg) {
   return n;
 }
 
+esp_err_t client_registry_set_uv_protection(uint32_t client_id, bool enabled) {
+  for (size_t i = 0; i < CLIENT_REGISTRY_MAX; i++) {
+    if (s_clients[i].active && s_clients[i].info.id == client_id) {
+      s_clients[i].info.uv_protection_enabled = enabled;
+      return ESP_OK;
+    }
+  }
+  return ESP_ERR_NOT_FOUND;
+}
+
+esp_err_t client_registry_get_uv_protection(uint32_t client_id,
+                                            bool *enabled_out) {
+  if (enabled_out == NULL) {
+    return ESP_ERR_INVALID_ARG;
+  }
+  const client_info_t *info = client_registry_find_by_id(client_id);
+  if (info == NULL) {
+    return ESP_ERR_NOT_FOUND;
+  }
+  *enabled_out = info->uv_protection_enabled;
+  return ESP_OK;
+}
+
+size_t client_registry_set_uv_protection_all(bool enabled) {
+  size_t n = 0;
+  for (size_t i = 0; i < CLIENT_REGISTRY_MAX; i++) {
+    if (!s_clients[i].active) {
+      continue;
+    }
+    s_clients[i].info.uv_protection_enabled = enabled;
+    n++;
+  }
+  return n;
+}
+
 static void clear_client_accel(client_slot_t *slot) {
   if (slot == NULL) {
     return;

main/client_registry.h

@@ -47,6 +47,8 @@ typedef struct {
   uint32_t lipo1_mv;
   uint32_t lipo2_mv;
   uint32_t battery_updated_at;
+  /** Master cache: software UV protection enabled on slave (default false). */
+  bool uv_protection_enabled;
   /** Master: last ESPNOW_ASSIGN_ID send time (rate-limit resends). */
   uint32_t last_assign_sent_at;
 } client_info_t;
@@ -119,6 +121,11 @@ esp_err_t client_registry_get_tap_config(uint32_t client_id,
                                          bma456_tap_config_t *cfg_out);
 size_t client_registry_set_tap_config_all(const bma456_tap_config_t *cfg);
 
+esp_err_t client_registry_set_uv_protection(uint32_t client_id, bool enabled);
+esp_err_t client_registry_get_uv_protection(uint32_t client_id,
+                                            bool *enabled_out);
+size_t client_registry_set_uv_protection_all(bool enabled);
+
 /** Store latest accel sample from a slave (matched by sender MAC). */
 esp_err_t client_registry_update_accel(const uint8_t mac[CLIENT_MAC_LEN],
                                        uint32_t slave_id, int16_t x, int16_t y,

main/cmd/cmd_battery_uv.c

@@ -0,0 +1,118 @@
+#include "cmd_battery_uv.h"
+#include "client_registry.h"
+#include "esp_log.h"
+#include "esp_now_comm.h"
+#include "pod_settings.h"
+#include "uart_cmd.h"
+
+static const char *TAG = "[BATTERY_UV_CMD]";
+
+static void reply(uint32_t client_id, bool success, bool enabled, bool latched,
+                  uint32_t slaves_updated) {
+  alox_UartMessage response;
+  uart_cmd_init_response(&response, alox_MessageType_BATTERY_UV,
+                         alox_UartMessage_battery_uv_response_tag);
+  response.payload.battery_uv_response.client_id = client_id;
+  response.payload.battery_uv_response.success = success;
+  response.payload.battery_uv_response.enabled = enabled;
+  response.payload.battery_uv_response.latched = latched;
+  response.payload.battery_uv_response.slaves_updated = slaves_updated;
+  uart_cmd_send(&response, TAG);
+}
+
+static esp_err_t apply_local_uv(bool enabled) {
+  esp_err_t err = pod_settings_set_uv_enabled(enabled);
+  if (err != ESP_OK) {
+    return err;
+  }
+  if (!enabled) {
+    (void)pod_settings_clear_uv_latched();
+  }
+  return ESP_OK;
+}
+
+static esp_err_t push_uv_to_slave(const client_info_t *client, bool enabled) {
+  if (client == NULL) {
+    return ESP_ERR_INVALID_ARG;
+  }
+  esp_err_t err = client_registry_set_uv_protection(client->id, enabled);
+  if (err != ESP_OK) {
+    return err;
+  }
+  return esp_now_comm_send_battery_uv(client->mac, client->id, enabled);
+}
+
+static void handle_battery_uv(const uint8_t *data, size_t len) {
+  alox_UartMessage uart_msg;
+  alox_BatteryUvRequest req = alox_BatteryUvRequest_init_zero;
+
+  if (uart_cmd_decode(data, len, &uart_msg) != ESP_OK) {
+    ESP_LOGW(TAG, "decode failed");
+    reply(0, false, pod_settings_is_uv_enabled(), pod_settings_is_uv_latched(),
+          0);
+    return;
+  }
+
+  const alox_BatteryUvRequest *req_ptr = UART_CMD_REQ(
+      &uart_msg, alox_UartMessage_battery_uv_request_tag, battery_uv_request);
+  if (req_ptr != NULL) {
+    req = *req_ptr;
+  }
+
+  if (req.write) {
+    if (req.all_clients) {
+      (void)client_registry_set_uv_protection_all(req.enabled);
+      uint32_t sent = 0;
+      for (size_t i = 0; i < client_registry_count(); i++) {
+        const client_info_t *client = client_registry_at(i);
+        if (client == NULL) {
+          continue;
+        }
+        if (esp_now_comm_send_battery_uv(client->mac, client->id,
+                                         req.enabled) == ESP_OK) {
+          sent++;
+        }
+      }
+
+      bool local_ok = apply_local_uv(req.enabled) == ESP_OK;
+      ESP_LOGI(TAG, "UV protection %s local=%d slaves=%u",
+               req.enabled ? "on" : "off", local_ok, (unsigned)sent);
+      reply(0, local_ok || sent > 0, req.enabled,
+            pod_settings_is_uv_latched(), sent);
+      return;
+    }
+
+    if (req.client_id == 0) {
+      esp_err_t err = apply_local_uv(req.enabled);
+      reply(0, err == ESP_OK, pod_settings_is_uv_enabled(),
+            pod_settings_is_uv_latched(), 0);
+      return;
+    }
+
+    const client_info_t *client = client_registry_find_by_id(req.client_id);
+    if (client == NULL) {
+      ESP_LOGW(TAG, "client id %lu not found", (unsigned long)req.client_id);
+      reply(req.client_id, false, req.enabled, false, 0);
+      return;
+    }
+
+    esp_err_t err = push_uv_to_slave(client, req.enabled);
+    reply(req.client_id, err == ESP_OK, req.enabled, false,
+          err == ESP_OK ? 1 : 0);
+    return;
+  }
+
+  if (req.all_clients || req.client_id == 0) {
+    reply(0, true, pod_settings_is_uv_enabled(), pod_settings_is_uv_latched(),
+          0);
+    return;
+  }
+
+  bool enabled = true;
+  esp_err_t err = client_registry_get_uv_protection(req.client_id, &enabled);
+  reply(req.client_id, err == ESP_OK, enabled, false, 0);
+}
+
+void cmd_battery_uv_register(void) {
+  uart_cmd_register(alox_MessageType_BATTERY_UV, handle_battery_uv);
+}

main/cmd/cmd_battery_uv.h

@@ -0,0 +1,6 @@
+#ifndef CMD_BATTERY_UV_H
+#define CMD_BATTERY_UV_H
+
+void cmd_battery_uv_register(void);
+
+#endif

main/cmd/cmd_client_info.c

@@ -31,6 +31,7 @@ static bool encode_clients_list(pb_ostream_t *stream, const pb_field_t *field,
     proto.tap_notify_single = client->tap_notify_single;
     proto.tap_notify_double = client->tap_notify_double;
     proto.tap_notify_triple = client->tap_notify_triple;
+    proto.uv_protection_enabled = client->uv_protection_enabled;
     proto.mac.funcs.encode = uart_cmd_encode_bytes;
     proto.mac.arg = &mac;
 

main/esp_now_comm.h

@@ -31,6 +31,10 @@ esp_err_t esp_now_comm_send_tap_config(const uint8_t mac[CLIENT_MAC_LEN],
                                        uint32_t client_id,
                                        const bma456_tap_config_t *cfg);
 
+/** Master: unicast software UV protection enable to one slave. */
+esp_err_t esp_now_comm_send_battery_uv(const uint8_t mac[CLIENT_MAC_LEN],
+                                       uint32_t client_id, bool enabled);
+
 /** Master: send minimal unicast test payload to verify master→slave path. */
 esp_err_t esp_now_comm_send_unicast_test(const uint8_t mac[CLIENT_MAC_LEN],
                                          uint32_t seq);

main/esp_now_master.c

@@ -75,6 +75,16 @@ static esp_err_t send_tap_config(const uint8_t *dest_mac, uint32_t client_id,
   return esp_now_core_send(dest_mac, &msg);
 }
 
+static esp_err_t send_battery_uv(const uint8_t *dest_mac, uint32_t client_id,
+                                 bool enabled) {
+  alox_EspNowMessage msg = alox_EspNowMessage_init_zero;
+  msg.type = alox_EspNowMessageType_ESPNOW_SET_BATTERY_UV;
+  msg.which_payload = alox_EspNowMessage_battery_uv_tag;
+  msg.payload.battery_uv.client_id = client_id;
+  msg.payload.battery_uv.enabled = enabled;
+  return esp_now_core_send(dest_mac, &msg);
+}
+
 static esp_err_t send_unicast_test(const uint8_t *dest_mac, uint32_t seq) {
   alox_EspNowMessage msg = alox_EspNowMessage_init_zero;
   msg.type = alox_EspNowMessageType_ESPNOW_UNICAST_TEST;
@@ -537,6 +547,24 @@ esp_err_t esp_now_comm_send_tap_config(const uint8_t mac[CLIENT_MAC_LEN],
   return err;
 }
 
+esp_err_t esp_now_comm_send_battery_uv(const uint8_t mac[CLIENT_MAC_LEN],
+                                       uint32_t client_id, bool enabled) {
+  if (mac == NULL || !esp_now_core_is_master()) {
+    return ESP_ERR_INVALID_STATE;
+  }
+  char mac_str[18];
+  esp_now_core_mac_to_str(mac, mac_str, sizeof(mac_str));
+  esp_err_t err = send_battery_uv(mac, client_id, enabled);
+  if (err == ESP_OK) {
+    ESP_LOGI(TAG, "unicast SET_BATTERY_UV to %s: enabled=%d client_id=%lu",
+             mac_str, enabled, (unsigned long)client_id);
+  } else {
+    ESP_LOGW(TAG, "unicast SET_BATTERY_UV to %s failed: %s", mac_str,
+             esp_err_to_name(err));
+  }
+  return err;
+}
+
 static void handle_accel_sample(const uint8_t mac[CLIENT_MAC_LEN],
                                 const alox_EspNowAccelSample *sample) {
   if (sample == NULL) {

main/esp_now_slave.c

@@ -640,6 +640,30 @@ static void handle_tap_config(const uint8_t *master_mac,
   }
 }
 
+static void handle_battery_uv(const uint8_t *master_mac,
+                              const alox_EspNowBatteryUv *msg) {
+  if (!client_id_matches(msg->client_id)) {
+    return;
+  }
+  if (s_joined && !esp_now_core_mac_equal(master_mac, s_master_mac)) {
+    return;
+  }
+
+  char mac_str[18];
+  esp_now_core_mac_to_str(master_mac, mac_str, sizeof(mac_str));
+  ESP_LOGI(TAG, "UV protection %s from master %s (id=%lu)",
+           msg->enabled ? "enabled" : "disabled", mac_str,
+           (unsigned long)my_client_id());
+
+  if (pod_settings_set_uv_enabled(msg->enabled) != ESP_OK) {
+    ESP_LOGW(TAG, "UV enable save failed");
+    return;
+  }
+  if (!msg->enabled) {
+    (void)pod_settings_clear_uv_latched();
+  }
+}
+
 static void handle_assign_id(const uint8_t *master_mac,
                              const alox_EspNowAssignId *msg) {
   if (!from_joined_master(master_mac)) {
@@ -853,6 +877,11 @@ void esp_now_slave_on_recv(const esp_now_recv_info_t *info, const uint8_t *data,
       handle_tap_config(info->src_addr, &msg.payload.tap_config);
     }
     break;
+  case alox_EspNowMessage_battery_uv_tag:
+    if (from_joined_master(info->src_addr)) {
+      handle_battery_uv(info->src_addr, &msg.payload.battery_uv);
+    }
+    break;
   case alox_EspNowMessage_accel_stream_tag:
     if (from_joined_master(info->src_addr)) {
       handle_accel_stream(info->src_addr, &msg.payload.accel_stream);

main/pod_settings.c

@@ -9,6 +9,7 @@ static const char *TAG = "[SETTINGS]";
 static const char *NS = "powerpod";
 static const char *KEY_ACCEL_DZ = "accel_dz";
 static const char *KEY_UV_LATCH = "uv_latch";
+static const char *KEY_UV_EN = "uv_en";
 static const char *KEY_TAP_CFG = "tap_cfg";
 static const char *KEY_ID_MAP = "id_map";
 static const char *KEY_ID_BIND = "id_bind";
@@ -325,6 +326,58 @@ esp_err_t pod_settings_clear_uv_latched(void) {
   return pod_settings_set_uv_latched(false);
 }
 
+bool pod_settings_is_uv_enabled(void) {
+  if (!s_nvs_ready) {
+    return false;
+  }
+
+  nvs_handle_t handle;
+  esp_err_t err = nvs_open(NS, NVS_READONLY, &handle);
+  if (err != ESP_OK) {
+    return false;
+  }
+
+  uint8_t value = 0;
+  err = nvs_get_u8(handle, KEY_UV_EN, &value);
+  nvs_close(handle);
+
+  if (err == ESP_ERR_NVS_NOT_FOUND) {
+    return false;
+  }
+  if (err != ESP_OK) {
+    return false;
+  }
+  return value != 0;
+}
+
+esp_err_t pod_settings_set_uv_enabled(bool enabled) {
+  esp_err_t err = ensure_nvs();
+  if (err != ESP_OK) {
+    return err;
+  }
+
+  nvs_handle_t handle;
+  err = nvs_open(NS, NVS_READWRITE, &handle);
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "nvs_open failed: %s", esp_err_to_name(err));
+    return err;
+  }
+
+  err = nvs_set_u8(handle, KEY_UV_EN, enabled ? 1u : 0u);
+  if (err == ESP_OK) {
+    err = nvs_commit(handle);
+  }
+  nvs_close(handle);
+
+  if (err != ESP_OK) {
+    ESP_LOGE(TAG, "save uv_en failed: %s", esp_err_to_name(err));
+    return err;
+  }
+
+  ESP_LOGI(TAG, "UV protection %s", enabled ? "enabled" : "disabled");
+  return ESP_OK;
+}
+
 esp_err_t pod_settings_load_id_map(pod_id_map_t *out) {
   if (out == NULL) {
     return ESP_ERR_INVALID_ARG;

main/pod_settings.h

@@ -35,6 +35,13 @@ bool pod_settings_is_uv_latched(void);
 esp_err_t pod_settings_set_uv_latched(bool latched);
 esp_err_t pod_settings_clear_uv_latched(void);
 
+/**
+ * Runtime enable for software UV protection (NVS). Missing key → disabled.
+ * Independent of POWERPOD_BATTERY_UV_ENABLE compile gate.
+ */
+bool pod_settings_is_uv_enabled(void);
+esp_err_t pod_settings_set_uv_enabled(bool enabled);
+
 /** Logical slave ids: 1…POD_CLIENT_ID_MAX (0 reserved for local master). */
 #define POD_CLIENT_ID_MIN 1u
 #define POD_CLIENT_ID_MAX 255u

main/powerpod.c

@@ -18,6 +18,7 @@
 #include "ota_confirm.h"
 #include "cmd_led_ring.h"
 #include "cmd_battery.h"
+#include "cmd_battery_uv.h"
 #include "cmd_set_log_level.h"
 #include "esp_now_comm.h"
 #include "powerpod.h"
@@ -233,6 +234,7 @@ void app_main(void) {
     cmd_client_id_map_reset_register();
     cmd_led_ring_register();
     cmd_battery_register();
+    cmd_battery_uv_register();
     cmd_ota_register();
     cmd_ota_slave_progress_register();
     cmd_set_log_level_register();

main/powerpod.h

@@ -3,7 +3,7 @@
 
 /** 1 = software LiPo UV latch + energy-save mode; 0 = disabled (LED mode 6 still works). */
 #ifndef POWERPOD_BATTERY_UV_ENABLE
-#define POWERPOD_BATTERY_UV_ENABLE 0
+#define POWERPOD_BATTERY_UV_ENABLE 1
 #endif
 
 #define DIP_MASTER 4

main/proto/esp_now_messages.pb.c

@@ -57,6 +57,9 @@ PB_BIND(alox_EspNowTapEvent, alox_EspNowTapEvent, AUTO)
 PB_BIND(alox_EspNowInputSendMode, alox_EspNowInputSendMode, AUTO)
 
 
+PB_BIND(alox_EspNowBatteryUv, alox_EspNowBatteryUv, AUTO)
+
+
 PB_BIND(alox_EspNowBatteryReport, alox_EspNowBatteryReport, AUTO)
 
 

main/proto/esp_now_messages.pb.h

@@ -38,7 +38,9 @@ typedef enum _alox_EspNowMessageType {
     /* * Master → slave: forget persisted master/id binding (debug reset). */
     alox_EspNowMessageType_ESPNOW_CLEAR_ID_BINDING = 23,
     /* * Master → slave: accel/tap ESP-NOW send path (best_effort/fast/wait/reliable). */
-    alox_EspNowMessageType_ESPNOW_SET_INPUT_SEND_MODE = 24
+    alox_EspNowMessageType_ESPNOW_SET_INPUT_SEND_MODE = 24,
+    /* * Master → slave: enable/disable software LiPo UV protection (NVS). */
+    alox_EspNowMessageType_ESPNOW_SET_BATTERY_UV = 25
 } alox_EspNowMessageType;
 
 /* Struct definitions */
@@ -161,6 +163,12 @@ typedef struct _alox_EspNowInputSendMode {
     uint32_t mode;
 } alox_EspNowInputSendMode;
 
+/* * Master → slave: software LiPo UV protection enable (persisted in NVS). */
+typedef struct _alox_EspNowBatteryUv {
+    uint32_t client_id; /* 0 = all slaves; otherwise only matching slave_id applies */
+    bool enabled;
+} alox_EspNowBatteryUv;
+
 /* * Slave → master: LiPo voltages (periodic ~30 s and on query). */
 typedef struct _alox_EspNowBatteryReport {
     uint32_t client_id;
@@ -236,6 +244,7 @@ typedef struct _alox_EspNowMessage {
         alox_EspNowAssignId assign_id;
         alox_EspNowClearIdBinding clear_id_binding;
         alox_EspNowInputSendMode input_send_mode;
+        alox_EspNowBatteryUv battery_uv;
     } payload;
 } alox_EspNowMessage;
 
@@ -246,8 +255,9 @@ extern "C" {
 
 /* Helper constants for enums */
 #define _alox_EspNowMessageType_MIN alox_EspNowMessageType_ESPNOW_UNKNOWN
-#define _alox_EspNowMessageType_MAX alox_EspNowMessageType_ESPNOW_SET_INPUT_SEND_MODE
-#define _alox_EspNowMessageType_ARRAYSIZE ((alox_EspNowMessageType)(alox_EspNowMessageType_ESPNOW_SET_INPUT_SEND_MODE+1))
+#define _alox_EspNowMessageType_MAX alox_EspNowMessageType_ESPNOW_SET_BATTERY_UV
+#define _alox_EspNowMessageType_ARRAYSIZE ((alox_EspNowMessageType)(alox_EspNowMessageType_ESPNOW_SET_BATTERY_UV+1))
+
 
 
 
@@ -293,6 +303,7 @@ extern "C" {
 #define alox_EspNowTapConfig_init_default        {0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
 #define alox_EspNowTapEvent_init_default         {0, 0}
 #define alox_EspNowInputSendMode_init_default    {0, 0}
+#define alox_EspNowBatteryUv_init_default        {0, 0}
 #define alox_EspNowBatteryReport_init_default    {0, 0, 0, 0, 0}
 #define alox_EspNowLedRing_init_default          {0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
 #define alox_EspNowOtaStart_init_default         {0}
@@ -317,6 +328,7 @@ extern "C" {
 #define alox_EspNowTapConfig_init_zero           {0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
 #define alox_EspNowTapEvent_init_zero            {0, 0}
 #define alox_EspNowInputSendMode_init_zero       {0, 0}
+#define alox_EspNowBatteryUv_init_zero           {0, 0}
 #define alox_EspNowBatteryReport_init_zero       {0, 0, 0, 0, 0}
 #define alox_EspNowLedRing_init_zero             {0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
 #define alox_EspNowOtaStart_init_zero            {0}
@@ -370,6 +382,8 @@ extern "C" {
 #define alox_EspNowTapEvent_kind_tag             2
 #define alox_EspNowInputSendMode_client_id_tag   1
 #define alox_EspNowInputSendMode_mode_tag        2
+#define alox_EspNowBatteryUv_client_id_tag       1
+#define alox_EspNowBatteryUv_enabled_tag         2
 #define alox_EspNowBatteryReport_client_id_tag   1
 #define alox_EspNowBatteryReport_lipo1_valid_tag 2
 #define alox_EspNowBatteryReport_lipo2_valid_tag 3
@@ -416,6 +430,7 @@ extern "C" {
 #define alox_EspNowMessage_assign_id_tag         23
 #define alox_EspNowMessage_clear_id_binding_tag  24
 #define alox_EspNowMessage_input_send_mode_tag   25
+#define alox_EspNowMessage_battery_uv_tag        26
 
 /* Struct field encoding specification for nanopb */
 #define alox_EspNowUnicastTest_FIELDLIST(X, a) \
@@ -531,6 +546,12 @@ X(a, STATIC,   SINGULAR, UINT32,   mode,              2)
 #define alox_EspNowInputSendMode_CALLBACK NULL
 #define alox_EspNowInputSendMode_DEFAULT NULL
 
+#define alox_EspNowBatteryUv_FIELDLIST(X, a) \
+X(a, STATIC,   SINGULAR, UINT32,   client_id,         1) \
+X(a, STATIC,   SINGULAR, BOOL,     enabled,           2)
+#define alox_EspNowBatteryUv_CALLBACK NULL
+#define alox_EspNowBatteryUv_DEFAULT NULL
+
 #define alox_EspNowBatteryReport_FIELDLIST(X, a) \
 X(a, STATIC,   SINGULAR, UINT32,   client_id,         1) \
 X(a, STATIC,   SINGULAR, BOOL,     lipo1_valid,       2) \
@@ -602,7 +623,8 @@ X(a, STATIC,   ONEOF,    MESSAGE,  (payload,echo_pong,payload.echo_pong),  21) \
 X(a, STATIC,   ONEOF,    MESSAGE,  (payload,tap_config,payload.tap_config),  22) \
 X(a, STATIC,   ONEOF,    MESSAGE,  (payload,assign_id,payload.assign_id),  23) \
 X(a, STATIC,   ONEOF,    MESSAGE,  (payload,clear_id_binding,payload.clear_id_binding),  24) \
-X(a, STATIC,   ONEOF,    MESSAGE,  (payload,input_send_mode,payload.input_send_mode),  25)
+X(a, STATIC,   ONEOF,    MESSAGE,  (payload,input_send_mode,payload.input_send_mode),  25) \
+X(a, STATIC,   ONEOF,    MESSAGE,  (payload,battery_uv,payload.battery_uv),  26)
 #define alox_EspNowMessage_CALLBACK NULL
 #define alox_EspNowMessage_DEFAULT NULL
 #define alox_EspNowMessage_payload_discover_MSGTYPE alox_EspNowDiscover
@@ -629,6 +651,7 @@ X(a, STATIC,   ONEOF,    MESSAGE,  (payload,input_send_mode,payload.input_send_m
 #define alox_EspNowMessage_payload_assign_id_MSGTYPE alox_EspNowAssignId
 #define alox_EspNowMessage_payload_clear_id_binding_MSGTYPE alox_EspNowClearIdBinding
 #define alox_EspNowMessage_payload_input_send_mode_MSGTYPE alox_EspNowInputSendMode
+#define alox_EspNowMessage_payload_battery_uv_MSGTYPE alox_EspNowBatteryUv
 
 extern const pb_msgdesc_t alox_EspNowUnicastTest_msg;
 extern const pb_msgdesc_t alox_EspNowEchoPing_msg;
@@ -647,6 +670,7 @@ extern const pb_msgdesc_t alox_EspNowTapNotify_msg;
 extern const pb_msgdesc_t alox_EspNowTapConfig_msg;
 extern const pb_msgdesc_t alox_EspNowTapEvent_msg;
 extern const pb_msgdesc_t alox_EspNowInputSendMode_msg;
+extern const pb_msgdesc_t alox_EspNowBatteryUv_msg;
 extern const pb_msgdesc_t alox_EspNowBatteryReport_msg;
 extern const pb_msgdesc_t alox_EspNowLedRing_msg;
 extern const pb_msgdesc_t alox_EspNowOtaStart_msg;
@@ -673,6 +697,7 @@ extern const pb_msgdesc_t alox_EspNowMessage_msg;
 #define alox_EspNowTapConfig_fields &alox_EspNowTapConfig_msg
 #define alox_EspNowTapEvent_fields &alox_EspNowTapEvent_msg
 #define alox_EspNowInputSendMode_fields &alox_EspNowInputSendMode_msg
+#define alox_EspNowBatteryUv_fields &alox_EspNowBatteryUv_msg
 #define alox_EspNowBatteryReport_fields &alox_EspNowBatteryReport_msg
 #define alox_EspNowLedRing_fields &alox_EspNowLedRing_msg
 #define alox_EspNowOtaStart_fields &alox_EspNowOtaStart_msg
@@ -691,6 +716,7 @@ extern const pb_msgdesc_t alox_EspNowMessage_msg;
 #define alox_EspNowAssignId_size                 6
 #define alox_EspNowBatteryQuery_size             6
 #define alox_EspNowBatteryReport_size            22
+#define alox_EspNowBatteryUv_size                8
 #define alox_EspNowClearIdBinding_size           0
 #define alox_EspNowDiscover_size                 19
 #define alox_EspNowEchoPing_size                 22

main/proto/esp_now_messages.proto

@@ -33,6 +33,8 @@ enum EspNowMessageType {
   ESPNOW_CLEAR_ID_BINDING = 23;
   /** Master → slave: accel/tap ESP-NOW send path (best_effort/fast/wait/reliable). */
   ESPNOW_SET_INPUT_SEND_MODE = 24;
+  /** Master → slave: enable/disable software LiPo UV protection (NVS). */
+  ESPNOW_SET_BATTERY_UV = 25;
 }
 
 message EspNowUnicastTest {
@@ -154,6 +156,12 @@ message EspNowInputSendMode {
   uint32 mode = 2;
 }
 
+/** Master → slave: software LiPo UV protection enable (persisted in NVS). */
+message EspNowBatteryUv {
+  uint32 client_id = 1; // 0 = all slaves; otherwise only matching slave_id applies
+  bool enabled = 2;
+}
+
 /** Slave → master: LiPo voltages (periodic ~30 s and on query). */
 message EspNowBatteryReport {
   uint32 client_id = 1;
@@ -225,5 +233,6 @@ message EspNowMessage {
     EspNowAssignId assign_id = 23;
     EspNowClearIdBinding clear_id_binding = 24;
     EspNowInputSendMode input_send_mode = 25;
+    EspNowBatteryUv battery_uv = 26;
   }
 }

main/proto/uart_messages.pb.c

@@ -48,6 +48,12 @@ PB_BIND(alox_InputSendModeRequest, alox_InputSendModeRequest, AUTO)
 PB_BIND(alox_InputSendModeResponse, alox_InputSendModeResponse, AUTO)
 
 
+PB_BIND(alox_BatteryUvRequest, alox_BatteryUvRequest, AUTO)
+
+
+PB_BIND(alox_BatteryUvResponse, alox_BatteryUvResponse, AUTO)
+
+
 PB_BIND(alox_BatteryStatusRequest, alox_BatteryStatusRequest, AUTO)
 
 

main/proto/uart_messages.pb.h

@@ -48,7 +48,11 @@ typedef enum _alox_MessageType {
     /* *
  Host → master: get/set slave ESP-NOW send path for accel/tap
  (best_effort / fast / wait / reliable). */
-    alox_MessageType_INPUT_SEND_MODE = 35
+    alox_MessageType_INPUT_SEND_MODE = 35,
+    /* *
+ Host → master: get/set software LiPo UV protection enable (NVS per pod).
+ client_id 0 = master; >0 = one slave; all_clients = master + every slave. */
+    alox_MessageType_BATTERY_UV = 36
 } alox_MessageType;
 
 /* *
@@ -98,6 +102,8 @@ typedef struct _alox_ClientInfo {
     bool tap_notify_single;
     bool tap_notify_double;
     bool tap_notify_triple;
+    /* * Master cache: software UV protection enabled on this slave (NVS on device). */
+    bool uv_protection_enabled;
 } alox_ClientInfo;
 
 typedef struct _alox_ClientInfoResponse {
@@ -167,6 +173,23 @@ typedef struct _alox_InputSendModeResponse {
     uint32_t slaves_updated;
 } alox_InputSendModeResponse;
 
+/* write=false: read UV enable; write=true: persist enable (and clear latch when disabling).
+ client_id 0 = local master; >0 = one slave; all_clients = master + every registered slave. */
+typedef struct _alox_BatteryUvRequest {
+    bool write;
+    bool enabled;
+    uint32_t client_id;
+    bool all_clients;
+} alox_BatteryUvRequest;
+
+typedef struct _alox_BatteryUvResponse {
+    uint32_t client_id;
+    bool success;
+    bool enabled;
+    bool latched;
+    uint32_t slaves_updated;
+} alox_BatteryUvResponse;
+
 /* * Host → master: read LiPo ADC voltages (master local and/or slaves via ESP-NOW). */
 typedef struct _alox_BatteryStatusRequest {
     /* * 0 = master only; >0 = one slave; ignored when all_clients */
@@ -504,6 +527,8 @@ typedef struct _alox_UartMessage {
         alox_ClientIdMapResetResponse client_id_map_reset_response;
         alox_InputSendModeRequest input_send_mode_request;
         alox_InputSendModeResponse input_send_mode_response;
+        alox_BatteryUvRequest battery_uv_request;
+        alox_BatteryUvResponse battery_uv_response;
     } payload;
 } alox_UartMessage;
 
@@ -514,8 +539,8 @@ extern "C" {
 
 /* Helper constants for enums */
 #define _alox_MessageType_MIN alox_MessageType_UNKNOWN
-#define _alox_MessageType_MAX alox_MessageType_INPUT_SEND_MODE
-#define _alox_MessageType_ARRAYSIZE ((alox_MessageType)(alox_MessageType_INPUT_SEND_MODE+1))
+#define _alox_MessageType_MAX alox_MessageType_BATTERY_UV
+#define _alox_MessageType_ARRAYSIZE ((alox_MessageType)(alox_MessageType_BATTERY_UV+1))
 
 #define _alox_InputSendMode_MIN alox_InputSendMode_INPUT_SEND_BEST_EFFORT
 #define _alox_InputSendMode_MAX alox_InputSendMode_INPUT_SEND_RELIABLE
@@ -549,6 +574,8 @@ extern "C" {
 
 
 
+
+
 #define alox_TapEvent_kind_ENUMTYPE alox_TapKind
 
 
@@ -587,7 +614,7 @@ extern "C" {
 #define alox_Ack_init_default                    {0}
 #define alox_EchoPayload_init_default            {{{NULL}, NULL}}
 #define alox_VersionResponse_init_default        {0, {{NULL}, NULL}, {{NULL}, NULL}}
-#define alox_ClientInfo_init_default             {0, 0, 0, {{NULL}, NULL}, 0, 0, 0, 0, 0, 0, 0}
+#define alox_ClientInfo_init_default             {0, 0, 0, {{NULL}, NULL}, 0, 0, 0, 0, 0, 0, 0, 0}
 #define alox_ClientInfoResponse_init_default     {{{NULL}, NULL}}
 #define alox_ClientInput_init_default            {0, 0, 0, 0}
 #define alox_ClientInputResponse_init_default    {{{NULL}, NULL}}
@@ -597,6 +624,8 @@ extern "C" {
 #define alox_AccelStreamResponse_init_default    {0, 0, 0, 0}
 #define alox_InputSendModeRequest_init_default   {0, _alox_InputSendMode_MIN, 0, 0}
 #define alox_InputSendModeResponse_init_default  {0, _alox_InputSendMode_MIN, 0, 0}
+#define alox_BatteryUvRequest_init_default       {0, 0, 0, 0}
+#define alox_BatteryUvResponse_init_default      {0, 0, 0, 0, 0}
 #define alox_BatteryStatusRequest_init_default   {0, 0}
 #define alox_LipoReading_init_default            {0, 0}
 #define alox_BatterySample_init_default          {0, false, alox_LipoReading_init_default, false, alox_LipoReading_init_default, 0}
@@ -638,7 +667,7 @@ extern "C" {
 #define alox_Ack_init_zero                       {0}
 #define alox_EchoPayload_init_zero               {{{NULL}, NULL}}
 #define alox_VersionResponse_init_zero           {0, {{NULL}, NULL}, {{NULL}, NULL}}
-#define alox_ClientInfo_init_zero                {0, 0, 0, {{NULL}, NULL}, 0, 0, 0, 0, 0, 0, 0}
+#define alox_ClientInfo_init_zero                {0, 0, 0, {{NULL}, NULL}, 0, 0, 0, 0, 0, 0, 0, 0}
 #define alox_ClientInfoResponse_init_zero        {{{NULL}, NULL}}
 #define alox_ClientInput_init_zero               {0, 0, 0, 0}
 #define alox_ClientInputResponse_init_zero       {{{NULL}, NULL}}
@@ -648,6 +677,8 @@ extern "C" {
 #define alox_AccelStreamResponse_init_zero       {0, 0, 0, 0}
 #define alox_InputSendModeRequest_init_zero      {0, _alox_InputSendMode_MIN, 0, 0}
 #define alox_InputSendModeResponse_init_zero     {0, _alox_InputSendMode_MIN, 0, 0}
+#define alox_BatteryUvRequest_init_zero          {0, 0, 0, 0}
+#define alox_BatteryUvResponse_init_zero         {0, 0, 0, 0, 0}
 #define alox_BatteryStatusRequest_init_zero      {0, 0}
 #define alox_LipoReading_init_zero               {0, 0}
 #define alox_BatterySample_init_zero             {0, false, alox_LipoReading_init_zero, false, alox_LipoReading_init_zero, 0}
@@ -702,6 +733,7 @@ extern "C" {
 #define alox_ClientInfo_tap_notify_single_tag    9
 #define alox_ClientInfo_tap_notify_double_tag    10
 #define alox_ClientInfo_tap_notify_triple_tag    11
+#define alox_ClientInfo_uv_protection_enabled_tag 12
 #define alox_ClientInfoResponse_clients_tag      1
 #define alox_ClientInput_id_tag                  1
 #define alox_ClientInput_lage_x_tag              2
@@ -733,6 +765,15 @@ extern "C" {
 #define alox_InputSendModeResponse_mode_tag      2
 #define alox_InputSendModeResponse_client_id_tag 3
 #define alox_InputSendModeResponse_slaves_updated_tag 4
+#define alox_BatteryUvRequest_write_tag          1
+#define alox_BatteryUvRequest_enabled_tag        2
+#define alox_BatteryUvRequest_client_id_tag      3
+#define alox_BatteryUvRequest_all_clients_tag    4
+#define alox_BatteryUvResponse_client_id_tag     1
+#define alox_BatteryUvResponse_success_tag       2
+#define alox_BatteryUvResponse_enabled_tag       3
+#define alox_BatteryUvResponse_latched_tag       4
+#define alox_BatteryUvResponse_slaves_updated_tag 5
 #define alox_BatteryStatusRequest_client_id_tag  1
 #define alox_BatteryStatusRequest_all_clients_tag 2
 #define alox_LipoReading_valid_tag               1
@@ -901,6 +942,8 @@ extern "C" {
 #define alox_UartMessage_client_id_map_reset_response_tag 43
 #define alox_UartMessage_input_send_mode_request_tag 44
 #define alox_UartMessage_input_send_mode_response_tag 45
+#define alox_UartMessage_battery_uv_request_tag  46
+#define alox_UartMessage_battery_uv_response_tag 47
 
 /* Struct field encoding specification for nanopb */
 #define alox_UartMessage_FIELDLIST(X, a) \
@@ -944,7 +987,9 @@ X(a, STATIC,   ONEOF,    MESSAGE,  (payload,ble_stream_tick,payload.ble_stream_t
 X(a, STATIC,   ONEOF,    MESSAGE,  (payload,client_id_map_reset_request,payload.client_id_map_reset_request),  42) \
 X(a, STATIC,   ONEOF,    MESSAGE,  (payload,client_id_map_reset_response,payload.client_id_map_reset_response),  43) \
 X(a, STATIC,   ONEOF,    MESSAGE,  (payload,input_send_mode_request,payload.input_send_mode_request),  44) \
-X(a, STATIC,   ONEOF,    MESSAGE,  (payload,input_send_mode_response,payload.input_send_mode_response),  45)
+X(a, STATIC,   ONEOF,    MESSAGE,  (payload,input_send_mode_response,payload.input_send_mode_response),  45) \
+X(a, STATIC,   ONEOF,    MESSAGE,  (payload,battery_uv_request,payload.battery_uv_request),  46) \
+X(a, STATIC,   ONEOF,    MESSAGE,  (payload,battery_uv_response,payload.battery_uv_response),  47)
 #define alox_UartMessage_CALLBACK NULL
 #define alox_UartMessage_DEFAULT NULL
 #define alox_UartMessage_payload_ack_payload_MSGTYPE alox_Ack
@@ -987,6 +1032,8 @@ X(a, STATIC,   ONEOF,    MESSAGE,  (payload,input_send_mode_response,payload.inp
 #define alox_UartMessage_payload_client_id_map_reset_response_MSGTYPE alox_ClientIdMapResetResponse
 #define alox_UartMessage_payload_input_send_mode_request_MSGTYPE alox_InputSendModeRequest
 #define alox_UartMessage_payload_input_send_mode_response_MSGTYPE alox_InputSendModeResponse
+#define alox_UartMessage_payload_battery_uv_request_MSGTYPE alox_BatteryUvRequest
+#define alox_UartMessage_payload_battery_uv_response_MSGTYPE alox_BatteryUvResponse
 
 #define alox_Ack_FIELDLIST(X, a) \
 
@@ -1016,7 +1063,8 @@ X(a, STATIC,   SINGULAR, UINT32,   version,           7) \
 X(a, STATIC,   SINGULAR, BOOL,     accel_stream_enabled,   8) \
 X(a, STATIC,   SINGULAR, BOOL,     tap_notify_single,   9) \
 X(a, STATIC,   SINGULAR, BOOL,     tap_notify_double,  10) \
-X(a, STATIC,   SINGULAR, BOOL,     tap_notify_triple,  11)
+X(a, STATIC,   SINGULAR, BOOL,     tap_notify_triple,  11) \
+X(a, STATIC,   SINGULAR, BOOL,     uv_protection_enabled,  12)
 #define alox_ClientInfo_CALLBACK pb_default_field_callback
 #define alox_ClientInfo_DEFAULT NULL
 
@@ -1089,6 +1137,23 @@ X(a, STATIC,   SINGULAR, UINT32,   slaves_updated,    4)
 #define alox_InputSendModeResponse_CALLBACK NULL
 #define alox_InputSendModeResponse_DEFAULT NULL
 
+#define alox_BatteryUvRequest_FIELDLIST(X, a) \
+X(a, STATIC,   SINGULAR, BOOL,     write,             1) \
+X(a, STATIC,   SINGULAR, BOOL,     enabled,           2) \
+X(a, STATIC,   SINGULAR, UINT32,   client_id,         3) \
+X(a, STATIC,   SINGULAR, BOOL,     all_clients,       4)
+#define alox_BatteryUvRequest_CALLBACK NULL
+#define alox_BatteryUvRequest_DEFAULT NULL
+
+#define alox_BatteryUvResponse_FIELDLIST(X, a) \
+X(a, STATIC,   SINGULAR, UINT32,   client_id,         1) \
+X(a, STATIC,   SINGULAR, BOOL,     success,           2) \
+X(a, STATIC,   SINGULAR, BOOL,     enabled,           3) \
+X(a, STATIC,   SINGULAR, BOOL,     latched,           4) \
+X(a, STATIC,   SINGULAR, UINT32,   slaves_updated,    5)
+#define alox_BatteryUvResponse_CALLBACK NULL
+#define alox_BatteryUvResponse_DEFAULT NULL
+
 #define alox_BatteryStatusRequest_FIELDLIST(X, a) \
 X(a, STATIC,   SINGULAR, UINT32,   client_id,         1) \
 X(a, STATIC,   SINGULAR, BOOL,     all_clients,       2)
@@ -1389,6 +1454,8 @@ extern const pb_msgdesc_t alox_AccelStreamRequest_msg;
 extern const pb_msgdesc_t alox_AccelStreamResponse_msg;
 extern const pb_msgdesc_t alox_InputSendModeRequest_msg;
 extern const pb_msgdesc_t alox_InputSendModeResponse_msg;
+extern const pb_msgdesc_t alox_BatteryUvRequest_msg;
+extern const pb_msgdesc_t alox_BatteryUvResponse_msg;
 extern const pb_msgdesc_t alox_BatteryStatusRequest_msg;
 extern const pb_msgdesc_t alox_LipoReading_msg;
 extern const pb_msgdesc_t alox_BatterySample_msg;
@@ -1442,6 +1509,8 @@ extern const pb_msgdesc_t alox_OtaSlaveProgressResponse_msg;
 #define alox_AccelStreamResponse_fields &alox_AccelStreamResponse_msg
 #define alox_InputSendModeRequest_fields &alox_InputSendModeRequest_msg
 #define alox_InputSendModeResponse_fields &alox_InputSendModeResponse_msg
+#define alox_BatteryUvRequest_fields &alox_BatteryUvRequest_msg
+#define alox_BatteryUvResponse_fields &alox_BatteryUvResponse_msg
 #define alox_BatteryStatusRequest_fields &alox_BatteryStatusRequest_msg
 #define alox_LipoReading_fields &alox_LipoReading_msg
 #define alox_BatterySample_fields &alox_BatterySample_msg
@@ -1497,6 +1566,8 @@ extern const pb_msgdesc_t alox_OtaSlaveProgressResponse_msg;
 #define alox_BatterySample_size                  32
 #define alox_BatteryStatusRequest_size           8
 #define alox_BatteryStatusResponse_size          580
+#define alox_BatteryUvRequest_size               12
+#define alox_BatteryUvResponse_size              18
 #define alox_BleStreamTick_size                  753
 #define alox_CacheClientAccel_size               26
 #define alox_CacheClientStatus_size              44

main/proto/uart_messages.proto

@@ -47,6 +47,11 @@ enum MessageType {
    * (best_effort / fast / wait / reliable).
    */
   INPUT_SEND_MODE = 35;
+  /**
+   * Host → master: get/set software LiPo UV protection enable (NVS per pod).
+   * client_id 0 = master; >0 = one slave; all_clients = master + every slave.
+   */
+  BATTERY_UV = 36;
 }
 
 message UartMessage {
@@ -92,6 +97,8 @@ message UartMessage {
     ClientIdMapResetResponse client_id_map_reset_response = 43;
     InputSendModeRequest input_send_mode_request = 44;
     InputSendModeResponse input_send_mode_response = 45;
+    BatteryUvRequest battery_uv_request = 46;
+    BatteryUvResponse battery_uv_response = 47;
   }
 }
 
@@ -122,6 +129,8 @@ message ClientInfo {
   bool tap_notify_single = 9;
   bool tap_notify_double = 10;
   bool tap_notify_triple = 11;
+  /** Master cache: software UV protection enabled on this slave (NVS on device). */
+  bool uv_protection_enabled = 12;
 }
 
 message ClientInfoResponse { 
@@ -202,6 +211,23 @@ message InputSendModeResponse {
   uint32 slaves_updated = 4;
 }
 
+// write=false: read UV enable; write=true: persist enable (and clear latch when disabling).
+// client_id 0 = local master; >0 = one slave; all_clients = master + every registered slave.
+message BatteryUvRequest {
+  bool write = 1;
+  bool enabled = 2;
+  uint32 client_id = 3;
+  bool all_clients = 4;
+}
+
+message BatteryUvResponse {
+  uint32 client_id = 1;
+  bool success = 2;
+  bool enabled = 3;
+  bool latched = 4;
+  uint32 slaves_updated = 5;
+}
+
 /** Host → master: read LiPo ADC voltages (master local and/or slaves via ESP-NOW). */
 message BatteryStatusRequest {
   /** 0 = master only; >0 = one slave; ignored when all_clients */