Merge pull request #11527 from daijoubu/feature/msp-dronecan-support

DroneCAN: Add node table, CLI status, and MSP2 node query commands

Author: sensei-hacker

docs/DroneCAN-Driver.md

@@ -242,6 +242,38 @@ dronecanUpdate(micros());  // Called repeatedly
 
 ---
 
+### Node Table
+
+The driver maintains a table of detected DroneCAN nodes populated from incoming `NodeStatus` broadcasts.
+
+#### `dronecanNodeInfo_t` struct
+
+```c
+typedef struct dronecanNodeInfo_s {
+    uint8_t  nodeID;              // CAN node ID (1-127)
+    uint8_t  health;              // UAVCAN_PROTOCOL_NODESTATUS_HEALTH_*
+    uint8_t  mode;                // UAVCAN_PROTOCOL_NODESTATUS_MODE_*
+    uint32_t uptime_sec;          // Node uptime in seconds
+    uint16_t vendor_status_code;  // Vendor-specific status word
+    uint32_t last_seen_ms;        // FC millis() timestamp of last NodeStatus
+    uint8_t  name_len;            // Length of name (0 until GetNodeInfo implemented)
+    char     name[32];            // Node name, zero-padded
+} dronecanNodeInfo_t;
+```
+
+The table holds up to `DRONECAN_MAX_NODES` (32) entries, indexed by arrival order. Entries are never removed at runtime; the table persists from boot until power-off.
+
+#### Accessor Functions
+
+| Function | Returns |
+|----------|---------|
+| `dronecanGetNodeCount()` | Number of unique nodes seen (`uint8_t`) |
+| `dronecanGetNode(uint8_t index)` | Pointer to `dronecanNodeInfo_t` for entry `index`, or `NULL` if out of range |
+| `dronecanGetState()` | Current bus state (`dronecanState_e`) |
+| `dronecanGetBitrateKbps()` | Configured bitrate as a plain integer (e.g. 1000) |
+
+---
+
 ### Configuration
 
 #### Settings
@@ -305,8 +337,8 @@ The driver includes 7 built-in message handlers. Each handler decodes a message
 
 #### `handle_NodeStatus()`
 **Receives:** `uavcan_protocol_NodeStatus` (from other nodes)
-**Processing:** Decodes and logs node health (OK/WARNING/ERROR/CRITICAL) and mode (OPERATIONAL/INITIALIZATION/MAINTENANCE/SOFTWARE_UPDATE/OFFLINE)
-**Status:** Logs health and mode status
+**Processing:** Decodes the message and upserts into the node table (`nodeTable[]`). If the source node ID is already in the table, health, mode, uptime, vendor status, and `last_seen_ms` are updated. If it is a new node and the table is not full, a new entry is appended and `activeNodeCount` is incremented. Node names are not available from NodeStatus broadcasts; they remain empty until `GetNodeInfo` service requests are implemented.
+**Status:** Node count accessible via `dronecanGetNodeCount()`; per-node detail via `dronecanGetNode()`
 
 ### Service Handlers
 
@@ -477,6 +509,46 @@ if (uavcan_equipment_gnss_Fix_decode(transfer, &gnssFix) == 0) {
 
 ---
 
+## MSP Commands
+
+Two MSP2 commands expose the node table to external tools (configurator, GCS, test scripts):
+
+### `MSP2_INAV_DRONECAN_NODES` (0x2042)
+
+**Direction:** Request (no payload) → Reply  
+**Handler location:** `mspFcProcessOutCommand()` in `fc_msp.c`  
+**Guard:** `#ifdef USE_DRONECAN`
+
+**Reply layout:**
+
+| Offset | Size | Field |
+|--------|------|-------|
+| 0 | 1 | `nodeCount` |
+| 1 + N×30 | 1 | `nodeID` |
+| 2 + N×30 | 1 | `health` |
+| 3 + N×30 | 1 | `mode` |
+| 4 + N×30 | 4 | `uptime_sec` (little-endian) |
+| 8 + N×30 | 2 | `vendor_status_code` |
+| 10 + N×30 | 4 | `last_seen_ms` |
+| 14 + N×30 | 1 | `name_len` |
+| 15 + N×30 | 16 | `name` (zero-padded) |
+
+Total: 1 + nodeCount × 30 bytes.
+
+---
+
+### `MSP2_INAV_DRONECAN_NODE_INFO` (0x2043)
+
+**Direction:** Request (1 byte node ID) → Reply  
+**Handler location:** `mspFCProcessInOutCommand()` in `fc_msp.c`  
+**Guard:** `#ifdef USE_DRONECAN`
+
+**Request:** 1 byte — target `nodeID`
+
+**Reply layout:** same fields as above but with a 32-byte `name` field (46 bytes total). Returns an empty response if the requested node ID is not in the table.
+
+---
+
 ## Adding New Message Types
 
 To add support for a new DroneCAN message type:
@@ -837,6 +909,7 @@ void broadcastNodeStatus(void) {
 
 | Date | Version | Changes |
 |---|---|---|
+| 2026-04-30 | 1.2 | Added node table (`dronecanNodeInfo_t`), accessor functions, CLI status output, and MSP commands (0x2042/0x2043) |
 | 2026-02-18 | 1.1 | Added error recovery, graceful disable behavior, and safe initialization documentation |
 | 2026-02-16 | 1.0 | Initial version - handler-based architecture documentation |
 

docs/DroneCAN.md

@@ -318,6 +318,40 @@ Connect the CAN bus lines between your flight controller and DroneCAN peripheral
     120R                          (pass-through)                              120R
 ```
 
+## Diagnostics
+
+### CLI Status
+
+The `status` CLI command includes a DroneCAN summary line showing the current bus state and how many nodes have been detected:
+
+```
+DroneCAN: nodeID=10, bitrate=1000 kbps, status=NORMAL, nodes=2
+```
+
+| Field | Description |
+|-------|-------------|
+| `nodeID` | This FC's CAN node ID |
+| `bitrate` | Configured CAN bus bitrate |
+| `status` | `INIT`, `NORMAL`, or `BUS_OFF` |
+| `nodes` | Number of unique nodes seen since boot |
+
+### MSP Commands
+
+Two MSP2 commands are available for querying detected DroneCAN nodes programmatically (e.g. from a GCS or configurator):
+
+| Command | Code | Description |
+|---------|------|-------------|
+| `MSP2_INAV_DRONECAN_NODES` | `0x2042` | Returns count and status of all detected nodes |
+| `MSP2_INAV_DRONECAN_NODE_INFO` | `0x2043` | Returns full detail for a single node by ID |
+
+**`MSP2_INAV_DRONECAN_NODES` response:** one byte node count followed by 7-byte records — nodeID(1), health(1), mode(1), last\_seen\_ms(4). Maximum payload is 1 + 32×7 = 225 bytes, well within the 512-byte MSP output buffer.
+
+**`MSP2_INAV_DRONECAN_NODE_INFO` request/response:** send a single-byte node ID; receive full node detail — nodeID, health, mode, uptime\_sec, vendor\_status\_code, last\_seen\_ms, name\_len, and name (32 bytes). Returns `MSP_RESULT_ERROR` if the node ID is not in the table.
+
+See `docs/development/msp/README.md` for the full MSP field layout.
+
+---
+
 ## Troubleshooting
 
 ### No data from DroneCAN devices

docs/development/msp/README.md

@@ -417,6 +417,8 @@ When the MSP JSON specification changes, bump `msp_messages.json` version:
 [8251 - MSP2_INAV_LOGIC_CONDITIONS_SINGLE](#msp2_inav_logic_conditions_single)  
 [8256 - MSP2_INAV_ESC_RPM](#msp2_inav_esc_rpm)  
 [8257 - MSP2_INAV_ESC_TELEM](#msp2_inav_esc_telem)  
+[8258 - MSP2_INAV_DRONECAN_NODES](#msp2_inav_dronecan_nodes)  
+[8259 - MSP2_INAV_DRONECAN_NODE_INFO](#msp2_inav_dronecan_node_info)  
 [8264 - MSP2_INAV_LED_STRIP_CONFIG_EX](#msp2_inav_led_strip_config_ex)  
 [8265 - MSP2_INAV_SET_LED_STRIP_CONFIG_EX](#msp2_inav_set_led_strip_config_ex)  
 [8266 - MSP2_INAV_FW_APPROACH](#msp2_inav_fw_approach)  
@@ -450,6 +452,7 @@ When the MSP JSON specification changes, bump `msp_messages.json` version:
 [8736 - MSP2_INAV_FULL_LOCAL_POSE](#msp2_inav_full_local_pose)  
 [8737 - MSP2_INAV_SET_WP_INDEX](#msp2_inav_set_wp_index)  
 [8739 - MSP2_INAV_SET_CRUISE_HEADING](#msp2_inav_set_cruise_heading)  
+[8752 - MSP2_INAV_SET_AUX_RC](#msp2_inav_set_aux_rc)  
 [12288 - MSP2_BETAFLIGHT_BIND](#msp2_betaflight_bind)  
 [12289 - MSP2_RX_BIND](#msp2_rx_bind)  
 
@@ -2311,7 +2314,7 @@ When the MSP JSON specification changes, bump `msp_messages.json` version:
 | `hdop` | `uint16_t` | 2 | HDOP * 100 | Horizontal Dilution of Precision (`gpsSol.hdop`) |
 | `eph` | `uint16_t` | 2 | cm | Estimated Horizontal Position Accuracy (`gpsSol.eph`) |
 | `epv` | `uint16_t` | 2 | cm | Estimated Vertical Position Accuracy (`gpsSol.epv`) |
-| `hwVersion` | `uint32_t` | 4 | Version code | GPS hardware version (`gpsState.hwVersion`). Values: 500=UBLOX5, 600=UBLOX6, 700=UBLOX7, 800=UBLOX8, 900=UBLOX9, 1000=UBLOX10, 0=UNKNOWN |
+| `hwVersion` | `uint8_t` | 1 | - | GPS hardware version bit-field: bits[7:6]=series (0b01=u-blox Neo/M), bits[5:0]=generation. E.g. 0x48=M8, 0x49=M9, 0x4A=M10, 0=unknown. |
 
 **Notes:** Requires `USE_GPS`.
 
@@ -4156,6 +4159,41 @@ When the MSP JSON specification changes, bump `msp_messages.json` version:
 
 **Notes:** Requires `USE_ESC_SENSOR`. See `escSensorData_t` in `sensors/esc_sensor.h` for the exact structure fields.
 
+## <a id="msp2_inav_dronecan_nodes"></a>`MSP2_INAV_DRONECAN_NODES (8258 / 0x2042)`
+**Description:** Returns the list of all detected DroneCAN nodes with their current status.  
+
+**Request Payload:** **None**  
+  
+**Reply Payload:**
+|Field|C Type|Size (Bytes)|Description|
+|---|---|---|---|
+| `nodeCount` | `uint8_t` | 1 | Number of detected DroneCAN nodes |
+| `nodeData` | `dronecanNodeStatus_t[]` | array | Array of per-node status records, one per detected node. Each record: nodeID(1)+health(1)+mode(1)+last_seen_ms(4) = 7 bytes. Full detail available via MSP2_INAV_DRONECAN_NODE_INFO. |
+
+**Notes:** Requires `USE_DRONECAN`. Response is `nodeCount` followed by `nodeCount` records of 7 bytes each: nodeID(1)+health(1)+mode(1)+last_seen_ms(4). Maximum payload 1 + (DRONECAN_MAX_NODES * 7) = 225 bytes. Full node detail including uptime, vendor status, and name is available via MSP2_INAV_DRONECAN_NODE_INFO.
+
+## <a id="msp2_inav_dronecan_node_info"></a>`MSP2_INAV_DRONECAN_NODE_INFO (8259 / 0x2043)`
+**Description:** Returns full status detail for a single DroneCAN node by ID.  
+  
+**Request Payload:**
+|Field|C Type|Size (Bytes)|Description|
+|---|---|---|---|
+| `nodeID` | `uint8_t` | 1 | DroneCAN node ID to query (1-127) |
+  
+**Reply Payload:**
+|Field|C Type|Size (Bytes)|Units|Description|
+|---|---|---|---|---|
+| `nodeID` | `uint8_t` | 1 | - | DroneCAN node ID |
+| `health` | `uint8_t` | 1 | - | Node health: 0=OK, 1=WARNING, 2=ERROR, 3=CRITICAL |
+| `mode` | `uint8_t` | 1 | - | Node mode: 0=OPERATIONAL, 1=INITIALIZATION, 2=MAINTENANCE, 3=SOFTWARE_UPDATE, 7=OFFLINE |
+| `uptime_sec` | `uint32_t` | 4 | s | Node uptime in seconds |
+| `vendor_status_code` | `uint16_t` | 2 | - | Vendor-specific status code |
+| `last_seen_ms` | `uint32_t` | 4 | ms | FC millisecond timestamp when this node was last seen |
+| `name_len` | `uint8_t` | 1 | - | Length of node name string (0 if unknown) |
+| `name` | `char[32]` | 32 | - | Node name up to 32 bytes, zero-padded |
+
+**Notes:** Requires `USE_DRONECAN`. Returns `MSP_RESULT_ERROR` if the requested node ID is not in the node table.
+
 ## <a id="msp2_inav_led_strip_config_ex"></a>`MSP2_INAV_LED_STRIP_CONFIG_EX (8264 / 0x2048)`
 **Description:** Retrieves the full configuration for each LED on the strip using the `ledConfig_t` structure. Supersedes `MSP_LED_STRIP_CONFIG`.  
 
@@ -4710,6 +4748,19 @@ When the MSP JSON specification changes, bump `msp_messages.json` version:
 
 **Notes:** Returns error if the aircraft is not armed or `NAV_COURSE_HOLD_MODE` is not active. On success, sets both `posControl.cruise.course` and `posControl.cruise.previousCourse` to the normalised value, preventing spurious heading adjustments from `getCruiseHeadingAdjustment()` on the next control cycle.
 
+## <a id="msp2_inav_set_aux_rc"></a>`MSP2_INAV_SET_AUX_RC (8752 / 0x2230)`
+**Description:** Bandwidth-efficient auxiliary RC channel update. Sets CH13-CH32 with configurable resolution (2/4/8/16-bit) without affecting primary flight controls. Designed for extending channel count beyond native RC link capacity via MSP passthrough.  
+  
+**Request Payload:**
+|Field|C Type|Size (Bytes)|Units|Description|
+|---|---|---|---|---|
+| `definitionByte` | `uint8_t` | 1 | - | Packed start channel and resolution. Bits 7-3: start channel index (valid range 12-31 for CH13-CH32; 0-11 rejected as error). Bits 2-0: resolution mode (0=2-bit, 1=4-bit, 2=8-bit, 3=16-bit; 4-7 reserved/error). |
+| `channelData` | `uint8_t[]` | array | PWM (encoded) | Packed channel values, sequential from start channel. Number of channels is derived from data size and resolution. Value 0 means skip (no update). Sub-byte modes (2-bit, 4-bit) are packed MSB-first. 2-bit values 1-3 map to 1000/1500/2000us. 4-bit values 1-15 map to 1000 + (val-1)*1000/14 us. 8-bit values 1-255 map to 1000 + (val-1)*1000/254 us. 16-bit values are direct PWM, clamped to 750-2250us. |
+
+**Reply Payload:** **None**  
+
+**Notes:** CH1-CH12 (index 0-11) are protected and will return `MSP_RESULT_ERROR`. Payload size must be 2-49 bytes. Constraint: `startChannel + channelCount <= 32`. Values persist until overwritten; no timeout. Applied as a post-RX overlay in `calculateRxChannelsAndUpdateFailsafe()` after MSP RC Override but before failsafe. Does not require `USE_RX_MSP` or MSP-RC-OVERRIDE flight mode. Does not affect failsafe detection. When MSP is the primary RX provider, channels covered by `MSP_SET_RAW_RC` are automatically skipped. Channels in the `mspOverrideChannels` bitmask are skipped when MSP RC Override mode is active. Recommended to send with `MSP_FLAG_DONT_REPLY` (flags=0x01) to save bandwidth on telemetry passthrough links. 16-bit mode requires even number of data bytes and values are clamped to 750-2250us.
+
 ## <a id="msp2_betaflight_bind"></a>`MSP2_BETAFLIGHT_BIND (12288 / 0x3000)`
 **Description:** Initiates the receiver binding procedure for supported serial protocols (CRSF, SRXL2).  
 

docs/development/msp/msp_messages.json

@@ -9817,6 +9817,100 @@
             "notes": "Requires `USE_ESC_SENSOR`. See `escSensorData_t` in `sensors/esc_sensor.h` for the exact structure fields.",
             "description": "Retrieves the full telemetry data structure reported by each ESC."
         },
+        "MSP2_INAV_DRONECAN_NODES": {
+            "code": 8258,
+            "mspv": 2,
+            "request": null,
+            "reply": {
+                "payload": [
+                    {
+                        "name": "nodeCount",
+                        "ctype": "uint8_t",
+                        "desc": "Number of detected DroneCAN nodes",
+                        "units": ""
+                    },
+                    {
+                        "name": "nodeData",
+                        "desc": "Array of per-node status records, one per detected node. Each record: nodeID(1)+health(1)+mode(1)+last_seen_ms(4) = 7 bytes. Full detail available via MSP2_INAV_DRONECAN_NODE_INFO.",
+                        "ctype": "dronecanNodeStatus_t",
+                        "array": true,
+                        "array_size": 0,
+                        "units": ""
+                    }
+                ]
+            },
+            "variable_len": true,
+            "notes": "Requires `USE_DRONECAN`. Response is `nodeCount` followed by `nodeCount` records of 7 bytes each: nodeID(1)+health(1)+mode(1)+last_seen_ms(4). Maximum payload 1 + (DRONECAN_MAX_NODES * 7) = 225 bytes. Full node detail including uptime, vendor status, and name is available via MSP2_INAV_DRONECAN_NODE_INFO.",
+            "description": "Returns the list of all detected DroneCAN nodes with their current status."
+        },                                                                                                        
+        "MSP2_INAV_DRONECAN_NODE_INFO": {                                                   
+            "code": 8259,                                                                                         
+            "mspv": 2,                                                                                            
+            "request": {
+                "payload": [                                                                                      
+                    {                                                                       
+                        "name": "nodeID",
+                        "ctype": "uint8_t",
+                        "desc": "DroneCAN node ID to query (1-127)",
+                        "units": ""                                                                               
+                    }
+                ]                                                                                                 
+            },                                                                              
+            "reply": {
+                "payload": [
+                    {
+                        "name": "nodeID",
+                        "ctype": "uint8_t",                                                                       
+                        "desc": "DroneCAN node ID",
+                        "units": ""                                                                               
+                    },                                                                      
+                    {
+                        "name": "health",
+                        "ctype": "uint8_t",
+                        "desc": "Node health: 0=OK, 1=WARNING, 2=ERROR, 3=CRITICAL",
+                        "units": ""
+                    },
+                    {
+                        "name": "mode",
+                        "ctype": "uint8_t",                                                                       
+                        "desc": "Node mode: 0=OPERATIONAL, 1=INITIALIZATION, 2=MAINTENANCE, 3=SOFTWARE_UPDATE, 7=OFFLINE",                                                                                                       
+                        "units": ""                                                         
+                    },                                                                                            
+                    {
+                        "name": "uptime_sec",                                                                     
+                        "ctype": "uint32_t",                                                
+                        "desc": "Node uptime in seconds",
+                        "units": "s"
+                    },
+                    {
+                        "name": "vendor_status_code",                                                             
+                        "ctype": "uint16_t",
+                        "desc": "Vendor-specific status code",                                                    
+                        "units": ""                                                         
+                    },
+                    {
+                        "name": "last_seen_ms",
+                        "ctype": "uint32_t",                                                                      
+                        "desc": "FC millisecond timestamp when this node was last seen",
+                        "units": "ms"                                                                             
+                    },                                                                      
+                    {
+                        "name": "name_len",
+                        "ctype": "uint8_t",                                                                       
+                        "desc": "Length of node name string (0 if unknown)",
+                        "units": ""                                                                               
+                    },                                                                      
+                    {
+                        "name": "name",
+                        "ctype": "char[32]",
+                        "desc": "Node name up to 32 bytes, zero-padded",                                          
+                        "units": ""
+                    }                                                                                             
+                ]                                                                           
+            },
+            "notes": "Requires `USE_DRONECAN`. Returns `MSP_RESULT_ERROR` if the requested node ID is not in the node table.",                                                                                                     
+            "description": "Returns full status detail for a single DroneCAN node by ID."
+        },                                        
         "MSP2_INAV_LED_STRIP_CONFIG_EX": {
             "code": 8264,
             "mspv": 2,