Snapshot iniziale: bridge telemetria CRSF->LTM/MAVLink (ESP-NOW)

Stato di partenza prima dei fix. Il repo git era inizializzato a meta'
(config.lock + objects/ mancante, zero commit): riparato.
my_config.h (UID reale, tutti e 3 i sottoprogetti) escluso via .gitignore;
aggiunto my_config.h.example. .pio/ escluso.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

02_telemetry_bridge/lib/EspNowCrsf/EspNowCrsf.cpp

@@ -0,0 +1,104 @@
+#include "EspNowCrsf.h"
+#include <WiFi.h>
+#include <esp_wifi.h>
+#include <esp_now.h>
+
+namespace EspNowCrsf {
+
+// ---- Ring buffer dei frame CRSF ----------------------------
+static const uint8_t  RING_SLOTS = 8;
+static const uint16_t SLOT_SIZE  = 64;
+
+struct Slot { uint8_t data[SLOT_SIZE]; uint16_t len; };
+static Slot         ring[RING_SLOTS];
+static volatile uint8_t  head = 0;   // scritto dalla callback
+static volatile uint8_t  tail = 0;   // letto dal loop
+static portMUX_TYPE      mux  = portMUX_INITIALIZER_UNLOCKED;
+
+static volatile uint32_t s_received = 0;
+static volatile uint32_t s_dropped  = 0;
+
+static uint8_t s_uid[6];
+
+// ---- Callback ricezione (firma arduino-esp32 core 2.x) -----
+static void onRecv(const uint8_t* mac, const uint8_t* in, int len) {
+    if (len <= 8 || in == nullptr) return;
+    // keep-alive: type/payload a zero subito dopo l'header di 8 byte
+    // (len > 9 prima degli accessi: con len==9 leggere in[9] sarebbe OOB)
+    if (len > 9 && in[8] == 0 && in[9] == 0) return;
+
+    uint16_t crsfLen = len - 8;
+    if (crsfLen > SLOT_SIZE) crsfLen = SLOT_SIZE;
+
+    portENTER_CRITICAL_ISR(&mux);
+    uint8_t next = (head + 1) % RING_SLOTS;
+    if (next == tail) {              // pieno -> scarta il piu' vecchio
+        tail = (tail + 1) % RING_SLOTS;
+        s_dropped++;
+    }
+    memcpy(ring[head].data, in + 8, crsfLen);
+    ring[head].len = crsfLen;
+    head = next;
+    s_received++;
+    portEXIT_CRITICAL_ISR(&mux);
+}
+
+void begin(const uint8_t uid[6]) {
+    memcpy(s_uid, uid, 6);
+    s_uid[0] &= ~0x01;               // MAC unicast
+
+    WiFi.mode(WIFI_STA);
+    WiFi.disconnect();
+    esp_wifi_set_protocol(WIFI_IF_STA, WIFI_PROTOCOL_11B);
+    esp_wifi_set_mac(WIFI_IF_STA, s_uid);
+    esp_wifi_start();
+    esp_wifi_set_channel(1, WIFI_SECOND_CHAN_NONE);
+
+    if (esp_now_init() != ESP_OK) return;
+    esp_now_register_recv_cb(onRecv);
+
+    // Peer broadcast per l'invio sperimentale (uplink)
+    esp_now_peer_info_t peer = {};
+    memset(peer.peer_addr, 0xFF, 6);     // broadcast
+    peer.channel = 1;
+    peer.encrypt = false;
+    esp_now_add_peer(&peer);
+}
+
+bool poll(uint8_t* out, uint16_t* outLen, uint16_t maxLen) {
+    bool got = false;
+    portENTER_CRITICAL(&mux);
+    if (tail != head) {
+        uint16_t n = ring[tail].len;
+        if (n > maxLen) n = maxLen;
+        memcpy(out, ring[tail].data, n);
+        *outLen = n;
+        tail = (tail + 1) % RING_SLOTS;
+        got = true;
+    }
+    portEXIT_CRITICAL(&mux);
+    return got;
+}
+
+uint32_t framesReceived() { return s_received; }
+uint32_t framesDropped()  { return s_dropped; }
+
+bool sendRaw(const uint8_t* data, uint16_t len) {
+    static const uint8_t bcast[6] = {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF};
+    return esp_now_send(bcast, data, len) == ESP_OK;
+}
+
+#ifdef UNIT_TEST
+void test_injectRaw(const uint8_t* data, uint16_t len) { onRecv(nullptr, data, len); }
+
+void test_reset() {
+    portENTER_CRITICAL(&mux);
+    head = 0;
+    tail = 0;
+    s_received = 0;
+    s_dropped = 0;
+    portEXIT_CRITICAL(&mux);
+}
+#endif
+
+} // namespace EspNowCrsf