Send Implement Hardware messages towards AgOpenGPS

AOGDissector.lua

@@ -7,7 +7,8 @@ ISOBUS_proto = Proto("ISOBUSVT", "AgISOStack")
 local MajorPGNs = {
     [0x7F] = "Steer module",
     [0xFE] = "From AutoSteer",
-    [0x70] = "ISOBUS"
+    [0x70] = "ISOBUS",
+    [0x80] = "AOG-TaskController"
 }
 local MinorPGNs = {
     [0x00] = "AOG -> ISOBUS",
@@ -111,7 +112,11 @@ local AOGFields = {
     genericSubnet = ProtoField.ipv4("GenericIP.IPSubnet", "Subnet", base.DEC),
     genericShortIPRange = ProtoField.string("GenericIP.IPSubnet", "Subnet", base.STRING),
 
-    freeFormMessage = ProtoField.string("Freeform.message", "Message", base.STRING)
+    freeFormMessage = ProtoField.string("Freeform.message", "Message", base.STRING),
+
+    hwMsgDuration = ProtoField.uint8("TaskController.HwMsgDuration", "Duration", base.DEC),
+    hwMsgColor = ProtoField.uint8("TaskController.HwMsgColor", "Background", base.DEC),
+    hwMsgText = ProtoField.string("TaskController.HwMsgText", "Message", base.STRING)
 }
 
 FixQuality = {
@@ -563,6 +568,17 @@ function AOGProtocol_proto.dissector(buffer, pinfo, tree)
             end
         end
 
+        if MajorPGN == 0x80 then -- 128 AOG-TaskController
+            if MinorPGN == 0xdd and buffer(4, 1):uint() > 2 then -- 221 hardware message
+                local textLength = buffer(4, 1):uint() - 2
+                subtree:add(AOGFields.hwMsgDuration, buffer(5, 1)):append_text(" (x10 render frames)")
+                subtree:add(AOGFields.hwMsgColor, buffer(6, 1)):append_text(buffer(6, 1):uint() == 0 and
+                                                                                " (Salmon, alert)" or " (Bisque, info)")
+                subtree:add(AOGFields.hwMsgText, buffer(7, textLength))
+                pinfo.cols.info = "TC hardware message: " .. buffer(7, textLength):string()
+            end
+        end
+
         if MajorPGN == 0x78 then -- From GPS module 120
         end
 

docs/PROTOCOL.md

@@ -128,8 +128,37 @@ All PGNs sent **by the TC to AgIO/AgValonia** use source `0x80`.
 
 | PGN | Name | Length | Frequency | Payload |
 |---|---|---|---|---|
+| `0xDD` (221) | Hardware message | 2 + T | On event | `[duration, colour, text0, text1, ...]` — `T` = UTF-8 text bytes |
 | `0xF0` (240) | Section heartbeat / state | 2 + ⌈N/8⌉ | 100 ms | `[mode, num_sections, byte0, byte1, ...]` |
 
+#### `0xDD` — Hardware message
+
+Displays a text banner across the top of the AgOpenGPS map so the operator can see TC state that would otherwise only reach the console log. Payload:
+
+- byte 0: `duration` — see the caveat below
+- byte 1: `colour` — `0` renders a Salmon background (alert), any other value renders Bisque (info). The TC sends `1` for info.
+- bytes 2..: the message text, UTF-8, **not** NUL-terminated
+
+The frame's `Length` field is therefore `text_bytes + 2`, and AOG reads exactly `Length - 2` bytes starting at wire offset 7. The TC caps text at 60 bytes and truncates on a UTF-8 character boundary — splitting a multi-byte sequence would render as U+FFFD, and the display label clips long text anyway.
+
+**`duration` is frames, not seconds.** AOG stores `duration × 10` into a counter that it decrements once per OpenGL render tick, so the banner lasts `duration × 10` redraws — roughly `duration` seconds at AOG's nominal 10 Hz, but it stretches or shrinks with frame rate. **A condition that persists must be re-sent**; do not send once with a large duration and expect the banner to hold. The operator can also dismiss a banner early by clicking it.
+
+**AgOpenGPS ignores the source byte for this PGN** — it dispatches on the PGN byte alone. The TC still sends `0x80` per §2.2.
+
+**Display is opt-in on the AOG side.** AgOpenGPS drops these frames unless *Config → Data → Hardware Messages* is enabled; the setting defaults to **off**. A correct implementation looks like a no-op until it is switched on, which is the first thing to check when testing. There is no corresponding TC-side setting — the TC always sends.
+
+Messages the TC currently emits:
+
+| Text | Colour | Duration | Trigger |
+|---|---|---|---|
+| `Implement: <name> (<n> sections, <w> m)` | Info | 5 | An implement with sections registers. The `, <w> m` clause is omitted when the DDOP has no usable geometry. |
+| `Implement lost: <name>` | Alert | 10 | A previously seen implement disappears from the client list. |
+| `TC address conflict: preferred address in use` | Alert | 20 | Another control function claiming `NAME::Function::TaskController` holds address `0xF7`. Re-sent every 15 s while true. |
+| `TC address conflict resolved` | Info | 5 | The above clears. |
+| `TECU failed to claim address 240` | Alert | 10 | Once at startup, when the TECU is enabled but could not claim its fixed address. |
+
+The conflict messages surface on the operator's screen what the TC already writes to its console log; the console warning remains and keeps its own 30 s throttle.
+
 #### `0xF0` — Section heartbeat / state
 
 Sent every 100 ms for each connected ISOBUS implement that has sections. The payload is:
@@ -170,7 +199,7 @@ The TC reads `settings.json` from a per-user config directory:
 | Key | Type | Default | Description |
 |---|---|---|---|
 | `subnet` | `int[3]` | `[192, 168, 5]` | First three octets of the LAN AgIO/AgValonia lives on. Used for NIC selection and broadcast destination. |
-| `tecuEnabled` | `bool` | `true` | If `true`, the TC also impersonates a Tractor ECU on the CAN bus (claims address 128, broadcasts Speed Messages/NMEA2000, announces Class 1 BasicTractorECUServer). Set `false` when the tractor already has a TECU. |
+| `tecuEnabled` | `bool` | `true` | If `true`, the TC also impersonates a Tractor ECU on the CAN bus (claims address 240, broadcasts Speed Messages/NMEA2000, announces Class 1 BasicTractorECUServer). Set `false` when the tractor already has a TECU. |
 | `nmeaSendEnabled` | `bool` | `true` | Enable cyclic NMEA2000 COG/SOG transmission. Requires `tecuEnabled`; the VT disables this control when no TECU interface exists. |
 | `aogHeartbeatEnabled` | `bool` | `true` | Send `0xF0` heartbeat to AgIO/AgValonia every 100 ms even with no implement. Disable for AOG < v6.8.2 beta 5. |
 | `vtEnabled` | `bool` | `true` | Register the Virtual Terminal client and display the TC UI when a VT is present. |
@@ -209,8 +238,8 @@ Two control functions, both claiming addresses via standard J1939-81 address cla
 
 | CF | NAME function | Address | Notes |
 |---|---|---|---|
-| Task Controller | `TaskController` (function code 61) | Preferred `233` (ISO 11783-10 MappingComputer). Walks if claimed. | Always present. |
-| Tractor ECU | `TractorECU` (function code 132) | Fixed `128` (non-arbitrary-address-capable per ISO 11783-9). | Only present if `tecuEnabled: true`. |
+| Task Controller | `TaskController` (function code 61) | Preferred `247` (ISO 11783-10 MappingComputer). Walks if claimed. | Always present. |
+| Tractor ECU | `TractorECU` (function code 132) | Fixed `240` (non-arbitrary-address-capable per ISO 11783-9). | Only present if `tecuEnabled: true`. |
 
 Common NAME fields: Industry Group `2` (Agricultural), Device Class `0`, Manufacturer Code `1407`, Identity `20`. Override these in `app.cpp` if you fork.
 

include/app.hpp

@@ -9,6 +9,7 @@
 #pragma once
 
 #include <boost/asio.hpp>
+#include <cstdint>
 #include <map>
 #include <memory>
 #include <string>
@@ -36,6 +37,21 @@ class Application
 	void stop();
 
 private:
+	struct ImplementDetails
+	{
+		std::string displayName = "No implement";
+		std::uint8_t sections = 0;
+		std::string widthText;
+		std::string boomOffsetText;
+	};
+
+	struct ImplementSnapshot
+	{
+		std::string displayName;
+		std::uint8_t sections = 0;
+		std::string widthText;
+	};
+
 	void send_task_controller_status_message();
 
 	bool setup_can_hardware();
@@ -54,6 +70,11 @@ class Application
 	void update_vt_status_strings(bool aogConnected);
 
 	void send_vt_string_if_changed(std::uint16_t objectID, const std::string &value);
+	void send_hardware_message(const std::string &text, std::uint8_t duration, std::uint8_t color);
+	ImplementDetails derive_implement_details(ClientState &state) const;
+
+	static constexpr std::uint8_t HW_MSG_ALERT = 0;
+	static constexpr std::uint8_t HW_MSG_INFO = 1;
 
 	std::shared_ptr<Settings> settings = std::make_shared<Settings>();
 	boost::asio::io_context ioContext = boost::asio::io_context();
@@ -85,5 +106,8 @@ class Application
 	std::uint32_t vtDisconnectedSinceMs = 0;
 	std::uint32_t lastVtStatusUpdateMs = 0;
 	std::uint32_t lastVtSectionUpdateMs = 0;
+	bool tcAddressConflictActive = false;
+	bool tecuAddressClaimFailed = false;
+	std::map<std::uint64_t, ImplementSnapshot> implementSnapshots;
 	std::map<std::uint16_t, std::string> lastVtStrings;
 };