Add ESPNOW wireless trainer mode

Author: robustini

include/trainer_api.h

@@ -0,0 +1,14 @@
+#pragma once
+
+#include <stdint.h>
+
+#if defined(PLATFORM_ESP32) || defined(PLATFORM_ESP8266)
+
+bool TrainerIsAvailable();
+bool TrainerIsPaired();
+bool TrainerIsPairing();
+const uint8_t *TrainerGetPeerMac();
+bool TrainerStartPairing();
+void TrainerForgetPeer();
+
+#endif

lib/MSP/msptypes.h

@@ -56,3 +56,11 @@
 #define MSP_ELRS_BACKPACK_GET_VERSION           0x0381  // get the bacpack firmware version
 #define MSP_ELRS_BACKPACK_GET_STATUS            0x0382  // get the status of the backpack
 #define MSP_ELRS_BACKPACK_SET_PTR               0x0383  // forwarded back to TX backpack
+
+#define MSP_ELRS_BACKPACK_CONFIG_TRAINER_MODE   0x32
+
+#define MSP_ELRS_BACKPACK_TRAINER_CHANNELS      0x0390
+#define MSP_ELRS_BACKPACK_TRAINER_PAIR_REQ      0x0391
+#define MSP_ELRS_BACKPACK_TRAINER_PAIR_ACK      0x0392
+#define MSP_ELRS_BACKPACK_TRAINER_FORGET        0x0393
+#define MSP_ELRS_BACKPACK_TRAINER_STATUS        0x0394

lib/config/config.cpp

@@ -12,9 +12,28 @@ TxBackpackConfig::Load()
     // Check if version number matches
     if (m_config.version != (uint32_t)(TX_BACKPACK_CONFIG_VERSION | TX_BACKPACK_CONFIG_MAGIC))
     {
-        // If not, revert to defaults for this version
-        DBGLN("EEPROM version mismatch! Resetting to defaults...");
-        SetDefaults();
+        // If a known previous version is detected, migrate in place; otherwise revert to defaults
+        if (m_config.version == (uint32_t)(4U | TX_BACKPACK_CONFIG_MAGIC))
+        {
+            m_config.version = TX_BACKPACK_CONFIG_VERSION | TX_BACKPACK_CONFIG_MAGIC;
+            memset(m_config.trainerPeerMac, 0, 6);
+            m_config.trainerMode = TRAINER_MODE_OFF;
+            m_modified = true;
+            Commit();
+        }
+        else if (m_config.version == (uint32_t)(5U | TX_BACKPACK_CONFIG_MAGIC))
+        {
+            // Version 5 → 6: added trainerMode field
+            m_config.version = TX_BACKPACK_CONFIG_VERSION | TX_BACKPACK_CONFIG_MAGIC;
+            m_config.trainerMode = TRAINER_MODE_OFF;
+            m_modified = true;
+            Commit();
+        }
+        else
+        {
+            DBGLN("EEPROM version mismatch! Resetting to defaults...");
+            SetDefaults();
+        }
     }
 }
 
@@ -54,6 +73,8 @@ TxBackpackConfig::SetDefaults()
     m_config.wifiService = WIFI_SERVICE_UPDATE;
     m_config.mavlinkListenPort = 14555;  // Default MavLink listen port
     m_config.mavlinkSendPort = 14550;    // Default MavLink send port
+    memset(m_config.trainerPeerMac, 0, 6);
+    m_config.trainerMode = TRAINER_MODE_OFF;
     m_modified = true;
     Commit();
 }
@@ -99,6 +120,7 @@ TxBackpackConfig::SetTelemMode(telem_mode_t mode)
     m_config.telemMode = mode;
     m_modified = true;
 }
+
 void
 TxBackpackConfig::SetMavlinkListenPort(uint16_t port)
 {
@@ -112,6 +134,38 @@ TxBackpackConfig::SetMavlinkSendPort(uint16_t port)
     m_config.mavlinkSendPort = port;
     m_modified = true;
 }
+
+bool
+TxBackpackConfig::IsTrainerPaired() const
+{
+    for (int i = 0; i < 6; i++)
+    {
+        if (m_config.trainerPeerMac[i] != 0) return true;
+    }
+    return false;
+}
+
+void
+TxBackpackConfig::SetTrainerPeer(const uint8_t mac[6])
+{
+    memcpy(m_config.trainerPeerMac, mac, 6);
+    m_modified = true;
+}
+
+void
+TxBackpackConfig::ClearTrainerPeer()
+{
+    memset(m_config.trainerPeerMac, 0, 6);
+    m_modified = true;
+}
+
+void
+TxBackpackConfig::SetTrainerMode(trainer_mode_t mode)
+{
+    m_config.trainerMode = mode;
+    m_modified = true;
+}
+
 #endif
 
 /////////////////////////////////////////////////////

lib/config/config.h

@@ -7,7 +7,7 @@
 #define VRX_BACKPACK_CONFIG_MAGIC   (0b10U << 30)
 #define TIMER_BACKPACK_CONFIG_MAGIC (0b11U << 30)
 
-#define TX_BACKPACK_CONFIG_VERSION      4
+#define TX_BACKPACK_CONFIG_VERSION      6
 #define VRX_BACKPACK_CONFIG_VERSION     5
 #define TIMER_BACKPACK_CONFIG_VERSION   3
 
@@ -24,6 +24,12 @@ typedef enum {
     BACKPACK_TELEM_MODE_BLUETOOTH,
 } telem_mode_t;
 
+typedef enum {
+    TRAINER_MODE_OFF,
+    TRAINER_MODE_MASTER,
+    TRAINER_MODE_SLAVE,
+} trainer_mode_t;
+
 #if defined(TARGET_TX_BACKPACK)
 
 typedef struct {
@@ -36,6 +42,8 @@ typedef struct {
     telem_mode_t      telemMode;
     uint16_t          mavlinkListenPort;
     uint16_t          mavlinkSendPort;
+    uint8_t           trainerPeerMac[6];
+    trainer_mode_t    trainerMode;       // persisted so it survives TLM_MODE reboots
 } tx_backpack_config_t;
 
 class TxBackpackConfig
@@ -54,6 +62,9 @@ class TxBackpackConfig
     telem_mode_t GetTelemMode() { return m_config.telemMode; }
     uint16_t GetMavlinkListenPort() const { return m_config.mavlinkListenPort; }
     uint16_t GetMavlinkSendPort() const { return m_config.mavlinkSendPort; }
+    const uint8_t *GetTrainerPeerMac() const { return m_config.trainerPeerMac; }
+    bool IsTrainerPaired() const;
+    trainer_mode_t GetTrainerMode() const { return m_config.trainerMode; }
 
     // Setters
     void SetStorageProvider(ELRS_EEPROM *eeprom);
@@ -66,6 +77,9 @@ class TxBackpackConfig
     void SetTelemMode(telem_mode_t mode);
     void SetMavlinkListenPort(uint16_t port);
     void SetMavlinkSendPort(uint16_t port);
+    void SetTrainerPeer(const uint8_t mac[6]);
+    void ClearTrainerPeer();
+    void SetTrainerMode(trainer_mode_t mode);
 
 private:
     tx_backpack_config_t    m_config;
@@ -225,4 +239,4 @@ class TimerBackpackConfig
 
 extern TimerBackpackConfig config;
 
-#endif
+#endif