Windowed module protocol: every op admitted inside a 3.4s window after the firmware's observed temp poll (cadence 3.5-4.2s measured, stuck-at-last-fetch stale mechanism proven and avoided), acquire/window with panic on dead heartbeat; noise column shows green on/off cycle phase, cable-missing state unchanged

noise.go

@@ -75,6 +75,8 @@ type noiser struct {
 	// phase. Latched across the down phase, where the missing carrier is our
 	// own doing and says nothing about the cable.
 	connected atomic.Bool
+	// The cycle's up phase: ports admin-up and the wire loud, training or frames.
+	radiating atomic.Bool
 }
 
 func newNoiser() (*noiser, error) {
@@ -113,14 +115,20 @@ func (n *noiser) names() []string {
 	return []string{n.eps[0].name, n.eps[1].name}
 }
 
-// Zero while the cable was there at the last verdict, one while it was not:
-// the shape the error cells already colour by, so absence paints as the fault
-// it is and presence as the usual green.
-func (n *noiser) missing() uint64 {
-	if n.connected.Load() {
-		return 0
+type noiseView struct {
+	missing uint64
+	on      bool
+}
+
+// missing is zero while the cable was there at the last verdict, one while it
+// was not: the shape the error cells already colour by, so absence paints as
+// the fault it is. on is the cycle's phase, presence granted.
+func (n *noiser) view() noiseView {
+	v := noiseView{on: n.radiating.Load()}
+	if !n.connected.Load() {
+		v.missing = 1
 	}
-	return 1
+	return v
 }
 
 // The ports were reachable when the noiser was built, so one that stops taking
@@ -173,6 +181,7 @@ func (n *noiser) run(done *atomic.Bool) {
 
 	for !done.Load() {
 		n.setLinks(fd, true)
+		n.radiating.Store(true)
 		linked := false
 		for end := time.Now().Add(noiseUpSpan); time.Now().Before(end) && !done.Load(); {
 			<-tick.C
@@ -190,6 +199,7 @@ func (n *noiser) run(done *atomic.Bool) {
 		n.connected.Store(linked)
 
 		n.setLinks(fd, false)
+		n.radiating.Store(false)
 		for end := time.Now().Add(noiseDownSpan); time.Now().Before(end) && !done.Load(); {
 			<-tick.C
 		}