feat: Support for Power Genius XL

app.go

@@ -41,6 +41,7 @@ import (
 	"hamlog/internal/rotator/pst"
 	"hamlog/internal/settings"
 	"hamlog/internal/antgenius"
+	"hamlog/internal/powergenius"
 	"hamlog/internal/ultrabeam"
 	"hamlog/internal/winkeyer"
 
@@ -146,6 +147,11 @@ const (
 	keyAntGeniusEnabled = "antgenius.enabled"
 	keyAntGeniusHost    = "antgenius.host"
 
+	// PowerGenius XL (4O3A) amplifier fan-mode control — Hardware → PowerGenius.
+	keyPGXLEnabled = "pgxl.enabled"
+	keyPGXLHost    = "pgxl.host"
+	keyPGXLPort    = "pgxl.port"
+
 	// WinKeyer CW keyer (serial) — Hardware → CW Keyer.
 	keyWKEnabled    = "winkeyer.enabled"
 	keyWKPort       = "winkeyer.port"
@@ -390,6 +396,7 @@ type App struct {
 	ultrabeam           *ultrabeam.Client // Ultrabeam antenna (TCP); nil when disabled
 	ubFollowStop        chan struct{}     // stops the "follow frequency" loop; nil when off
 	antgenius           *antgenius.Client   // Antenna Genius (4O3A) switch (TCP); nil when disabled
+	pgxl                *powergenius.Client // PowerGenius XL (4O3A) amp fan control (TCP); nil when disabled
 	audioMgr            *audio.Manager
 	qsoRec              *audio.Recorder // continuous QSO recorder (rolling pre-roll)
 	cwMu                sync.Mutex          // guards the CW decoder lifecycle
@@ -824,6 +831,8 @@ func (a *App) startup(ctx context.Context) {
 	a.startUltrabeam()
 	// Antenna Genius switch: connect in the background if enabled.
 	a.startAntGenius()
+	// PowerGenius XL amp fan control: connect in the background if enabled.
+	a.startPGXL()
 
 	// Autostart: launch the active profile's configured external programs that
 	// aren't already running (WSJT-X, JTAlert, rotator control, …). Background
@@ -7923,6 +7932,82 @@ func (a *App) AntGeniusDeselect(port int) error {
 	return a.antgenius.Activate(port, 0)
 }
 
+// ── PowerGenius XL (4O3A) amplifier fan control (TCP, default port 9006) ─────
+
+// PGXLSettings is the JSON shape for the Hardware → PowerGenius panel.
+type PGXLSettings struct {
+	Enabled bool   `json:"enabled"`
+	Host    string `json:"host"`
+	Port    int    `json:"port"`
+}
+
+func (a *App) GetPGXLSettings() (PGXLSettings, error) {
+	out := PGXLSettings{Port: 9006}
+	if a.settings == nil {
+		return out, fmt.Errorf("db not initialized")
+	}
+	m, err := a.settings.GetMany(a.ctx, keyPGXLEnabled, keyPGXLHost, keyPGXLPort)
+	if err != nil {
+		return out, err
+	}
+	out.Enabled = m[keyPGXLEnabled] == "1"
+	out.Host = m[keyPGXLHost]
+	if p, _ := strconv.Atoi(m[keyPGXLPort]); p > 0 && p <= 65535 {
+		out.Port = p
+	}
+	return out, nil
+}
+
+func (a *App) SavePGXLSettings(s PGXLSettings) error {
+	if a.settings == nil {
+		return fmt.Errorf("db not initialized")
+	}
+	if s.Port <= 0 || s.Port > 65535 {
+		s.Port = 9006
+	}
+	for k, v := range map[string]string{
+		keyPGXLEnabled: boolStr(s.Enabled),
+		keyPGXLHost:    strings.TrimSpace(s.Host),
+		keyPGXLPort:    strconv.Itoa(s.Port),
+	} {
+		if err := a.settings.Set(a.ctx, k, v); err != nil {
+			return err
+		}
+	}
+	a.startPGXL()
+	return nil
+}
+
+// startPGXL stops any existing client and starts a fresh one if enabled.
+func (a *App) startPGXL() {
+	if a.pgxl != nil {
+		a.pgxl.Stop()
+		a.pgxl = nil
+	}
+	s, err := a.GetPGXLSettings()
+	if err != nil || !s.Enabled || strings.TrimSpace(s.Host) == "" {
+		return
+	}
+	a.pgxl = powergenius.New(s.Host, s.Port)
+	_ = a.pgxl.Start()
+}
+
+// GetPGXLStatus returns the amp's fan/connection state for the UI poll.
+func (a *App) GetPGXLStatus() powergenius.Status {
+	if a.pgxl == nil {
+		return powergenius.Status{}
+	}
+	return a.pgxl.GetStatus()
+}
+
+// PGXLSetFanMode sets the amplifier fan mode (STANDARD | CONTEST | BROADCAST).
+func (a *App) PGXLSetFanMode(mode string) error {
+	if a.pgxl == nil {
+		return fmt.Errorf("PowerGenius not connected — enable it in Settings → PowerGenius")
+	}
+	return a.pgxl.SetFanMode(mode)
+}
+
 // --- WinKeyer (CW keyer) bindings ---
 
 // WKMacro is one CW message slot (F1…): a short label + the macro text, which

frontend/src/App.tsx

@@ -3382,7 +3382,7 @@ export default function App() {
 
       {/* ===== CW decoder strip (only when enabled AND mode is CW) ===== */}
       {cwOn && (
-        <div className="ml-2.5 my-1.5 w-[45%] flex items-center gap-2 rounded-md border border-emerald-300/70 bg-emerald-50/60 px-2 py-1.5 text-xs">
+        <div className="ml-2.5 mt-1.5 -mb-1 w-[45%] flex items-center gap-2 rounded-md border border-emerald-300/70 bg-emerald-50/60 px-2 py-1.5 text-xs">
           <Ear className={cn('size-4 shrink-0', cwStatus.active ? 'text-emerald-600' : 'text-muted-foreground')} />
           {/* Input-level meter — if this stays flat with a strong signal, the RX
               audio device is wrong/silent rather than a decode problem. */}

frontend/src/components/FlexPanel.tsx

@@ -4,6 +4,7 @@ import {
   GetFlexState, FlexSetPower, FlexSetTunePower, FlexTune, FlexSetVox, FlexSetVoxLevel, FlexSetVoxDelay,
   FlexSetProcessor, FlexSetProcessorLevel, FlexSetMon, FlexSetMonLevel, FlexSetMic,
   FlexMox, FlexAmpOperate,
+  GetPGXLStatus, PGXLSetFanMode,
   FlexSetAGCMode, FlexSetAGCThreshold, FlexSetAudioLevel,
   FlexSetNB, FlexSetNBLevel, FlexSetNR, FlexSetNRLevel, FlexSetANF, FlexSetANFLevel,
   FlexSetAPF, FlexSetAPFLevel, FlexSetCWSpeed, FlexSetCWPitch, FlexSetCWBreakInDelay,
@@ -215,6 +216,16 @@ export function FlexPanel() {
     return () => { alive = false; window.clearInterval(id); };
   }, []);
 
+  // PowerGenius XL direct connection (fan mode), independent of the Flex link.
+  const [pg, setPg] = useState<{ connected: boolean; fan_mode?: string }>({ connected: false });
+  useEffect(() => {
+    let alive = true;
+    const tick = async () => { try { const s: any = await GetPGXLStatus(); if (alive) setPg(s || { connected: false }); } catch {} };
+    tick();
+    const id = window.setInterval(tick, 2000);
+    return () => { alive = false; window.clearInterval(id); };
+  }, []);
+
   const change = (key: keyof FlexState, val: number | boolean | string, send: () => Promise<any>) => {
     hold.current[key] = Date.now() + 900;
     setSt((p) => ({ ...p, [key]: val }));
@@ -430,6 +441,22 @@ export function FlexPanel() {
               <span className="text-xs text-muted-foreground">
                 {st.amp_operate ? 'Amplifier is in line (transmitting through PA).' : 'Amplifier bypassed (standby).'}
               </span>
+              {/* Fan mode — only when the PowerGenius direct connection is up
+                  (configured in Settings → PowerGenius). */}
+              {pg.connected && (
+                <label className="flex items-center gap-1.5 text-xs">
+                  <span className="text-muted-foreground">Fan</span>
+                  <select
+                    value={(pg.fan_mode || 'CONTEST').toUpperCase()}
+                    onChange={(e) => { const v = e.target.value; setPg((s) => ({ ...s, fan_mode: v })); PGXLSetFanMode(v).catch(() => {}); }}
+                    className="h-8 rounded-md border border-orange-300 bg-card px-2 text-xs font-semibold text-orange-800 outline-none focus:border-orange-500"
+                  >
+                    <option value="STANDARD">Standard</option>
+                    <option value="CONTEST">Contest</option>
+                    <option value="BROADCAST">Broadcast</option>
+                  </select>
+                </label>
+              )}
               <div className="flex-1" />
               {st.amp_fault && st.amp_fault !== 'NONE' && (
                 <span className="px-2 py-1 rounded bg-rose-100 text-rose-800 text-xs font-bold">FAULT: {st.amp_fault}</span>

frontend/src/components/SettingsModal.tsx

@@ -13,6 +13,7 @@ import {
   GetRotatorSettings, SaveRotatorSettings, TestRotator, RotatorPark, RotatorStop,
   GetUltrabeamSettings, SaveUltrabeamSettings, TestUltrabeam,
   GetAntGeniusSettings, SaveAntGeniusSettings,
+  GetPGXLSettings, SavePGXLSettings,
   GetWinkeyerSettings, SaveWinkeyerSettings, ListSerialPorts,
   GetAudioSettings, SaveAudioSettings, ListAudioInputDevices, ListAudioOutputDevices, PickAudioFolder, TestPTT,
   GetClublogCtyInfo, SetClublogCtyEnabled, DownloadClublogCty,
@@ -172,6 +173,7 @@ type SectionId =
   | 'winkeyer'
   | 'antenna'
   | 'antgenius'
+  | 'pgxl'
   | 'audio';
 
 type TreeNode =
@@ -210,6 +212,7 @@ const TREE: TreeNode[] = [
       { kind: 'item', label: 'CW Keyer',             id: 'winkeyer' },
       { kind: 'item', label: 'Antenna',             id: 'antenna' },
       { kind: 'item', label: 'Antenna Genius',      id: 'antgenius' },
+      { kind: 'item', label: 'PowerGenius',         id: 'pgxl' },
       { kind: 'item', label: 'Audio devices',     id: 'audio' },
     ],
   },
@@ -236,6 +239,7 @@ const SECTION_LABELS: Partial<Record<SectionId, string>> = {
   winkeyer: 'CW Keyer',
   antenna: 'Antenna',
   antgenius: 'Antenna Genius',
+  pgxl: 'PowerGenius',
   audio: 'Audio devices',
 };
 
@@ -634,6 +638,9 @@ export function SettingsModal({ onClose, onSaved, initialSection, onMainPaneChan
   // Antenna Genius (4O3A) switch settings — TCP port is fixed at 9007.
   const [antgenius, setAntgenius] = useState<{ enabled: boolean; host: string }>({ enabled: false, host: '' });
 
+  // PowerGenius XL (4O3A) amp fan-control settings.
+  const [pgxl, setPgxl] = useState<{ enabled: boolean; host: string; port: number }>({ enabled: false, host: '', port: 9006 });
+
   // WinKeyer CW keyer settings + macro editor.
   type WKMac = { label: string; text: string };
   type WKSettings = {
@@ -892,6 +899,7 @@ export function SettingsModal({ onClose, onSaved, initialSection, onMainPaneChan
         setRotator(r);
         try { setUltrabeam(await GetUltrabeamSettings() as any); } catch {}
         try { setAntgenius(await GetAntGeniusSettings() as any); } catch {}
+        try { setPgxl(await GetPGXLSettings() as any); } catch {}
         setBackupCfg(b as any);
         setQslDefaults(qd as any);
         setExtSvc(es as any);
@@ -932,6 +940,7 @@ export function SettingsModal({ onClose, onSaved, initialSection, onMainPaneChan
         try { setRotator(await GetRotatorSettings() as any); } catch {}
         try { setUltrabeam(await GetUltrabeamSettings() as any); } catch {}
         try { setAntgenius(await GetAntGeniusSettings() as any); } catch {}
+        try { setPgxl(await GetPGXLSettings() as any); } catch {}
         try { setBackupCfg(await GetBackupSettings() as any); } catch {}
         try { setQslDefaults(await GetQSLDefaults() as any); } catch {}
         try { setExtSvc(await GetExternalServices() as any); } catch {}
@@ -1100,6 +1109,7 @@ export function SettingsModal({ onClose, onSaved, initialSection, onMainPaneChan
       await SaveRotatorSettings(rotator as any);
       await SaveUltrabeamSettings(ultrabeam as any);
       await SaveAntGeniusSettings(antgenius as any);
+      await SavePGXLSettings(pgxl as any);
       await SaveWinkeyerSettings(wk as any);
       await SaveAudioSettings(audioCfg as any);
       await SaveEmailSettings(emailCfg as any);
@@ -2052,6 +2062,46 @@ export function SettingsModal({ onClose, onSaved, initialSection, onMainPaneChan
     );
   }
 
+  function PGXLPanelSettings() {
+    return (
+      <>
+        <SectionHeader
+          title="PowerGenius XL"
+          hint="OpsLog reads the amp's operate state through the FlexRadio, but the fan mode is only reachable on the PowerGenius XL's own TCP control port. Enter its IP to add a fan-mode selector next to Operate in the FlexRadio panel."
+        />
+        <div className="space-y-4 max-w-xl">
+          <label className="flex items-center gap-2 text-sm cursor-pointer">
+            <Checkbox checked={pgxl.enabled} onCheckedChange={(c) => setPgxl((s) => ({ ...s, enabled: !!c }))} />
+            Enable PowerGenius fan control
+          </label>
+          <div className="grid grid-cols-3 gap-3">
+            <div className="space-y-1 col-span-2">
+              <Label>Host / IP</Label>
+              <Input
+                value={pgxl.host ?? ''}
+                onChange={(e) => setPgxl((s) => ({ ...s, host: e.target.value }))}
+                placeholder="192.168.1.70"
+                className="font-mono"
+              />
+            </div>
+            <div className="space-y-1">
+              <Label>TCP port</Label>
+              <Input
+                type="number" min={1} max={65535}
+                value={pgxl.port}
+                onChange={(e) => setPgxl((s) => ({ ...s, port: parseInt(e.target.value) || 9006 }))}
+                className="font-mono"
+              />
+            </div>
+          </div>
+          <p className="text-xs text-muted-foreground">
+            Default port is 9006. Once enabled, a fan-mode dropdown (Standard / Contest / Broadcast) appears next to the amplifier Operate button in the FlexRadio tab.
+          </p>
+        </div>
+      </>
+    );
+  }
+
   function RotatorPanel() {
     return (
       <>
@@ -3808,6 +3858,7 @@ export function SettingsModal({ onClose, onSaved, initialSection, onMainPaneChan
     winkeyer:       WinkeyerPanel,
     antenna:        UltrabeamPanel,
     antgenius:      AntGeniusPanelSettings,
+    pgxl:           PGXLPanelSettings,
     audio:          AudioPanel,
   };
 

frontend/wailsjs/go/main/App.d.ts

@@ -10,6 +10,7 @@ import {award} from '../models';
 import {awardref} from '../models';
 import {cluster} from '../models';
 import {extsvc} from '../models';
+import {powergenius} from '../models';
 import {winkeyer} from '../models';
 import {audio} from '../models';
 import {operating} from '../models';
@@ -272,6 +273,10 @@ export function GetMySQLSettings():Promise<main.MySQLSettings>;
 
 export function GetOnlineOperators():Promise<Array<main.ChatPresence>>;
 
+export function GetPGXLSettings():Promise<main.PGXLSettings>;
+
+export function GetPGXLStatus():Promise<powergenius.Status>;
+
 export function GetPOTAToken():Promise<string>;
 
 export function GetQSLDefaults():Promise<main.QSLDefaults>;
@@ -374,6 +379,8 @@ export function OpenExternalURL(arg1:string):Promise<void>;
 
 export function OperatingDefaultForBand(arg1:string):Promise<operating.BandDefault>;
 
+export function PGXLSetFanMode(arg1:string):Promise<void>;
+
 export function PickAudioFolder():Promise<string>;
 
 export function PickBackupFolder():Promise<string>;
@@ -486,6 +493,8 @@ export function SaveOperatingAntenna(arg1:operating.Antenna):Promise<operating.A
 
 export function SaveOperatingStation(arg1:operating.Station):Promise<operating.Station>;
 
+export function SavePGXLSettings(arg1:main.PGXLSettings):Promise<void>;
+
 export function SavePOTAToken(arg1:string):Promise<void>;
 
 export function SaveProfile(arg1:profile.Profile):Promise<profile.Profile>;

frontend/wailsjs/go/main/App.js

@@ -514,6 +514,14 @@ export function GetOnlineOperators() {
   return window['go']['main']['App']['GetOnlineOperators']();
 }
 
+export function GetPGXLSettings() {
+  return window['go']['main']['App']['GetPGXLSettings']();
+}
+
+export function GetPGXLStatus() {
+  return window['go']['main']['App']['GetPGXLStatus']();
+}
+
 export function GetPOTAToken() {
   return window['go']['main']['App']['GetPOTAToken']();
 }
@@ -718,6 +726,10 @@ export function OperatingDefaultForBand(arg1) {
   return window['go']['main']['App']['OperatingDefaultForBand'](arg1);
 }
 
+export function PGXLSetFanMode(arg1) {
+  return window['go']['main']['App']['PGXLSetFanMode'](arg1);
+}
+
 export function PickAudioFolder() {
   return window['go']['main']['App']['PickAudioFolder']();
 }
@@ -942,6 +954,10 @@ export function SaveOperatingStation(arg1) {
   return window['go']['main']['App']['SaveOperatingStation'](arg1);
 }
 
+export function SavePGXLSettings(arg1) {
+  return window['go']['main']['App']['SavePGXLSettings'](arg1);
+}
+
 export function SavePOTAToken(arg1) {
   return window['go']['main']['App']['SavePOTAToken'](arg1);
 }

frontend/wailsjs/go/models.ts

@@ -1473,6 +1473,22 @@ export namespace main {
 	        this.database = source["database"];
 	    }
 	}
+	export class PGXLSettings {
+	    enabled: boolean;
+	    host: string;
+	    port: number;
+	
+	    static createFrom(source: any = {}) {
+	        return new PGXLSettings(source);
+	    }
+	
+	    constructor(source: any = {}) {
+	        if ('string' === typeof source) source = JSON.parse(source);
+	        this.enabled = source["enabled"];
+	        this.host = source["host"];
+	        this.port = source["port"];
+	    }
+	}
 	export class POTAUnmatched {
 	    activator: string;
 	    date: string;
@@ -2109,6 +2125,33 @@ export namespace operating {
 
 }
 
+export namespace powergenius {
+	
+	export class Status {
+	    connected: boolean;
+	    host?: string;
+	    last_error?: string;
+	    state?: string;
+	    fan_mode?: string;
+	    temperature: number;
+	
+	    static createFrom(source: any = {}) {
+	        return new Status(source);
+	    }
+	
+	    constructor(source: any = {}) {
+	        if ('string' === typeof source) source = JSON.parse(source);
+	        this.connected = source["connected"];
+	        this.host = source["host"];
+	        this.last_error = source["last_error"];
+	        this.state = source["state"];
+	        this.fan_mode = source["fan_mode"];
+	        this.temperature = source["temperature"];
+	    }
+	}
+
+}
+
 export namespace profile {
 	
 	export class ProfileDB {

internal/powergenius/powergenius.go

@@ -0,0 +1,226 @@
+// Package powergenius drives a 4O3A PowerGenius XL amplifier over its TCP text
+// API (same "Genius Series" line protocol as the Antenna Genius). OpsLog reads
+// the amp's operate state via the FlexRadio amplifier object, but the fan mode
+// is a PGXL-only setting only reachable on the amp's own control port — hence
+// this small direct client. Commands are "C<id>|<cmd>\n"; replies are
+// "R<id>|0|<k=v …>" and asynchronous "S0|<k=v …>".
+package powergenius
+
+import (
+	"bufio"
+	"fmt"
+	"net"
+	"strconv"
+	"strings"
+	"sync"
+	"sync/atomic"
+	"time"
+)
+
+const (
+	defaultPort    = 9006
+	dialTimeout    = 5 * time.Second
+	ioTimeout      = 3 * time.Second
+	pollEvery      = 1500 * time.Millisecond
+	reconnectDelay = 2 * time.Second
+)
+
+// Status is the snapshot the UI renders (only the bits OpsLog needs).
+type Status struct {
+	Connected   bool    `json:"connected"`
+	Host        string  `json:"host,omitempty"`
+	LastError   string  `json:"last_error,omitempty"`
+	State       string  `json:"state,omitempty"`    // IDLE / TRANSMIT_A …
+	FanMode     string  `json:"fan_mode,omitempty"` // STANDARD / CONTEST / BROADCAST
+	Temperature float64 `json:"temperature"`
+}
+
+type Client struct {
+	host string
+	port int
+
+	mu     sync.Mutex // serialises command send/recv on the connection
+	conn   net.Conn
+	reader *bufio.Reader
+
+	statusMu sync.RWMutex
+	status   Status
+
+	cmdID   atomic.Int64
+	stop    chan struct{}
+	running bool
+}
+
+func New(host string, port int) *Client {
+	if port <= 0 || port > 65535 {
+		port = defaultPort
+	}
+	return &Client{host: host, port: port, stop: make(chan struct{}), status: Status{Host: host}}
+}
+
+func (c *Client) Start() error {
+	c.running = true
+	go c.pollLoop()
+	return nil
+}
+
+func (c *Client) Stop() {
+	if !c.running {
+		return
+	}
+	c.running = false
+	close(c.stop)
+	c.mu.Lock()
+	if c.conn != nil {
+		c.conn.Close()
+		c.conn = nil
+		c.reader = nil
+	}
+	c.mu.Unlock()
+}
+
+func (c *Client) GetStatus() Status {
+	c.statusMu.RLock()
+	defer c.statusMu.RUnlock()
+	return c.status
+}
+
+func (c *Client) setStatus(fn func(*Status)) {
+	c.statusMu.Lock()
+	fn(&c.status)
+	c.statusMu.Unlock()
+}
+
+// SetFanMode sets the amplifier fan mode (STANDARD | CONTEST | BROADCAST).
+func (c *Client) SetFanMode(mode string) error {
+	m := strings.ToUpper(strings.TrimSpace(mode))
+	switch m {
+	case "STANDARD", "CONTEST", "BROADCAST":
+	default:
+		return fmt.Errorf("powergenius: invalid fan mode %q", mode)
+	}
+	if _, err := c.command("setup fanmode=" + m); err != nil {
+		return err
+	}
+	c.setStatus(func(s *Status) { s.FanMode = m }) // optimistic
+	return nil
+}
+
+// SetOperate puts the amp in OPERATE (1) or STANDBY (0).
+func (c *Client) SetOperate(on bool) error {
+	v := "0"
+	if on {
+		v = "1"
+	}
+	_, err := c.command("operate=" + v)
+	return err
+}
+
+func (c *Client) pollLoop() {
+	t := time.NewTicker(pollEvery)
+	defer t.Stop()
+	for {
+		select {
+		case <-c.stop:
+			return
+		case <-t.C:
+			if err := c.ensureConnected(); err != nil {
+				c.setStatus(func(s *Status) { s.Connected = false; s.LastError = "dial: " + err.Error() })
+				continue
+			}
+			if _, err := c.command("status"); err != nil {
+				c.dropConn()
+				c.setStatus(func(s *Status) { s.Connected = false; s.LastError = err.Error() })
+			}
+		}
+	}
+}
+
+func (c *Client) ensureConnected() error {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.conn != nil {
+		return nil
+	}
+	conn, err := net.DialTimeout("tcp", net.JoinHostPort(c.host, strconv.Itoa(c.port)), dialTimeout)
+	if err != nil {
+		return err
+	}
+	c.conn = conn
+	c.reader = bufio.NewReader(conn)
+	// Discard the version banner the device sends on connect.
+	_ = conn.SetReadDeadline(time.Now().Add(ioTimeout))
+	_, _ = c.reader.ReadString('\n')
+	return nil
+}
+
+func (c *Client) dropConn() {
+	c.mu.Lock()
+	if c.conn != nil {
+		c.conn.Close()
+		c.conn = nil
+		c.reader = nil
+	}
+	c.mu.Unlock()
+}
+
+// command sends "C<id>|<cmd>\n" and parses the single-line reply into status.
+func (c *Client) command(cmd string) (string, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if c.conn == nil || c.reader == nil {
+		return "", fmt.Errorf("powergenius: not connected")
+	}
+	id := c.cmdID.Add(1)
+	_ = c.conn.SetWriteDeadline(time.Now().Add(ioTimeout))
+	if _, err := fmt.Fprintf(c.conn, "C%d|%s\n", id, cmd); err != nil {
+		return "", err
+	}
+	_ = c.conn.SetReadDeadline(time.Now().Add(ioTimeout))
+	line, err := c.reader.ReadString('\n')
+	if err != nil {
+		return "", err
+	}
+	line = strings.TrimSpace(line)
+	c.parse(line)
+	return line, nil
+}
+
+// parse handles "R<id>|0|<k=v …>" and "S0|<k=v …>" status lines.
+func (c *Client) parse(resp string) {
+	var data string
+	switch {
+	case strings.HasPrefix(resp, "R"):
+		p := strings.SplitN(resp, "|", 3)
+		if len(p) < 3 {
+			return
+		}
+		data = p[2]
+	case strings.HasPrefix(resp, "S"):
+		p := strings.SplitN(resp, "|", 2)
+		if len(p) < 2 {
+			return
+		}
+		data = p[1]
+	default:
+		return
+	}
+	c.statusMu.Lock()
+	c.status.Connected = true
+	c.status.LastError = ""
+	for _, pair := range strings.Fields(data) {
+		kv := strings.SplitN(pair, "=", 2)
+		if len(kv) != 2 {
+			continue
+		}
+		switch kv[0] {
+		case "state":
+			c.status.State = kv[1]
+		case "fanmode":
+			c.status.FanMode = strings.ToUpper(kv[1])
+		case "temp":
+			c.status.Temperature, _ = strconv.ParseFloat(kv[1], 64)
+		}
+	}
+	c.statusMu.Unlock()
+}