docs(rotator): name the Green Heron RT-21, which was already supported

The RT-21 speaks the Hy-Gain DCU-1 command set in its default protocol
setting, and internal/rotator/dcu1 has driven that since it landed —
AP1nnn/AM1 to point, AI1 to read back, over a COM port or over TCP.
Nothing was missing except a way to find it: "Green Heron" sat in a
parenthesis after "Hy-Gain DCU-1", which an operator scanning the list
for RT-21 does not see.

So the dropdown leads with the controller people actually own, and the
hint says the two things that decide whether it works: the RT-21's
protocol must be set to DCU-1 / Rotor-EZ (on GS-232 it belongs to the
GS-232 entry instead), and with the Ethernet option TCP reaches it
directly rather than through a serial-over-IP bridge, which is what the
hint used to imply was necessary.

The package doc now also records what is NOT here: the native Green
Heron protocol is a third command set, with 0.1° readback and a real
stop, and writing it from memory is exactly the mistake this repo warns
about for wire protocols.

app.go

@@ -17175,7 +17175,7 @@ var rotatorTypes = []RotatorTypeInfo{
 	{ID: "rotgenius", Label: "Rotator Genius (4O3A, native)", Network: true, DefaultPort: 9006},
 	{ID: "arco", Label: "GS-232 azimuth controller (microHAM ARCO, ERC)", Network: true, Serial: true, DefaultPort: 4001, DefaultBaud: 9600},
 	{ID: "erc", Label: "ERC-M by DF9GR (Yaesu G-5500 az/el)", Elevation: true, Network: true, Serial: true, DefaultPort: 4001, DefaultBaud: 19200},
-	{ID: "dcu1", Label: "Hy-Gain DCU-1 (RotorCard DXA, Rotor-EZ, Green Heron)", Network: true, Serial: true, DefaultPort: 4001, DefaultBaud: 4800},
+	{ID: "dcu1", Label: "Green Heron RT-21 / Hy-Gain DCU-1 (Rotor-EZ, RotorCard DXA)", Network: true, Serial: true, DefaultPort: 4001, DefaultBaud: 4800},
 	{ID: "spid", Label: "SPID / AlfaSpid (RAS, BIG-RAS, MD-01, MD-02)", Elevation: true, Serial: true, DefaultBaud: 600},
 	{ID: "easycomm", Label: "EasyComm II (SatPC32, Gpredict, K3NG…)", Elevation: true, Network: true, Serial: true, DefaultPort: 4533, DefaultBaud: 9600},
 }

changelog.json

@@ -11,7 +11,8 @@
       "OpsLog appears again after an update. The relaunch was starting the new build with its window hidden, so it ran with no window at all.",
       "Each satellite slice now gets both of its antennas, RX and TX, from its own band — the downlink slice was left with no transmit antenna at all.",
       "The satellite ground track no longer draws a straight line across the map when it crosses the antimeridian.",
-      "A correction you make on the transmit VFO is now kept for the whole pass, and remembered for that transponder. Doppler tracking used to undo it a second later."
+      "A correction you make on the transmit VFO is now kept for the whole pass, and remembered for that transponder. Doppler tracking used to undo it a second later.",
+      "The Green Heron RT-21 is named in the rotator list. It speaks the DCU-1 command set OpsLog already drives, over its COM port or straight over TCP with the Ethernet option — set the controller to DCU-1 / Rotor-EZ."
     ],
     "fr": [
       "Le tracé du ciel et la position passent dans leur propre colonne, à gauche de la carte. Largeur réglable, et la colonne se replie comme celle de droite.",
@@ -23,7 +24,8 @@
       "OpsLog réapparaît après une mise à jour. La relance démarrait la nouvelle version avec sa fenêtre masquée, donc sans aucune fenêtre.",
       "Chaque slice satellite reçoit désormais ses deux antennes, RX et TX, depuis sa propre bande — la slice de descente restait sans antenne d’émission.",
       "Le tracé au sol du satellite ne trace plus une ligne droite en travers de la carte lorsqu’il franchit l’antiméridien.",
-      "Une correction faite sur le VFO d’émission est désormais conservée pour toute la passe, et mémorisée pour ce transpondeur. Le suivi Doppler l’effaçait une seconde plus tard."
+      "Une correction faite sur le VFO d’émission est désormais conservée pour toute la passe, et mémorisée pour ce transpondeur. Le suivi Doppler l’effaçait une seconde plus tard.",
+      "Le Green Heron RT-21 est nommé dans la liste des rotators. Il parle le jeu de commandes DCU-1 que OpsLog pilote déjà, via son port COM ou directement en TCP avec l’option Ethernet — régler le contrôleur sur DCU-1 / Rotor-EZ."
     ]
   },
   {

internal/rotator/dcu1/dcu1.go

@@ -1,11 +1,18 @@
 // Package dcu1 drives rotator controllers that speak the Hy-Gain DCU-1 protocol,
 // over a serial COM port (or a raw TCP socket, e.g. a serial-over-IP bridge).
 //
-// DCU-1 is used by the Hy-Gain DCU-1, the Idiom Press Rotor-EZ, Green Heron
+// DCU-1 is used by the Hy-Gain DCU-1, the Green Heron RT-21, the Idiom Press
-// controllers, and the RotorCard DXA (hamsupply) for Yaesu DXA rotors. It is a
+// Rotor-EZ, and the RotorCard DXA (hamsupply) for Yaesu DXA rotors. It is a
 // DIFFERENT command set from Yaesu GS-232 (see internal/rotator/gs232):
 // semicolon-terminated, azimuth only.
 //
+// The RT-21 selects its protocol on the controller, and only its DCU-1 /
+// Rotor-EZ setting is this one — an RT-21 left on GS-232 belongs to the gs232
+// package instead. With the Ethernet option it is a TCP endpoint in its own
+// right, so the TCP transport below reaches it without a serial-over-IP
+// bridge. Its NATIVE Green Heron protocol is a third command set, with 0.1°
+// readback and a real stop, and is not implemented here.
+//
 // Commands (';' terminated — roundTrip appends the ';'):
 //
 //	AP1nnn   set the target bearing nnn (000-359)

wiki/Maps-and-Antennas.md

@@ -42,7 +42,7 @@ one of these.
 | **Rotator Genius** (4O3A) | Az | TCP, port 9006 | Native. *Rotator #* picks which of the two the box drives; *Two rotors* adds the second as its own rotor. |
 | **GS-232 azimuth** (microHAM ARCO, ERC) | Az | LAN or USB | Set the controller's CONTROL PROTOCOL to *Yaesu GS-232A*. An **ERC** must be in GS-232 emulation, **not** Hy-Gain DCU-1. |
 | **ERC-M by DF9GR** | Az + El | USB COM or LAN | The az/el interface for a **Yaesu G-5500** and its relatives. GS-232 emulation, 19200 baud out of the box. Pick this rather than the GS-232 azimuth entry: it is what tells OpsLog the mast has an elevation motor. |
-| **Hy-Gain DCU-1** | Az | COM port or serial-over-IP | RotorCard DXA, Idiom Press Rotor-EZ, Green Heron. A DCU-1 is 4800 baud; others may differ — match the controller. |
+| **Green Heron RT-21 / Hy-Gain DCU-1** | Az | COM port, or TCP | Also Idiom Press Rotor-EZ and RotorCard DXA. Set the RT-21 to DCU-1 / Rotor-EZ — on GS-232 use the GS-232 row instead. With the Ethernet option, TCP reaches it directly; no serial-over-IP bridge. A DCU-1 is 4800 baud; others may differ — match the controller. |
 | **SPID / AlfaSpid** | Az + El (Rot2Prog) | COM port | Native, so PstRotator is not needed in between. See below. |
 | **EasyComm II** | Az + El | COM port or TCP | What SatPC32, Gpredict, Hamlib and K3NG firmware speak — the usual choice for a home-built az/el controller. |