Disable flood adverts

prefs is 5 char length :nerd:

.github/workflows/pr-build-check.yml

@@ -0,0 +1,43 @@
+name: PR Build Check
+
+on:
+  pull_request:
+    branches: [main, dev]
+    paths:
+      - 'src/**'
+      - 'examples/**'
+      - 'variants/**'
+      - 'platformio.ini'
+      - '.github/workflows/pr-build-check.yml'
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        environment:
+          # ESP32-S3 (most common platform)
+          - Heltec_v3_companion_radio_ble
+          - Heltec_v3_repeater
+          - Heltec_v3_room_server
+          # nRF52
+          - RAK_4631_companion_radio_ble
+          - RAK_4631_repeater
+          - RAK_4631_room_server
+          # RP2040
+          - PicoW_repeater
+          # STM32
+          - wio-e5-mini_repeater
+          # ESP32-C6
+          - LilyGo_Tlora_C6_repeater_
+
+    steps:
+      - name: Clone Repo
+        uses: actions/checkout@v4
+
+      - name: Setup Build Environment
+        uses: ./.github/actions/setup-build-environment
+
+      - name: Build ${{ matrix.environment }}
+        run: pio run -e ${{ matrix.environment }}

boards/t_beams3_supreme.json

@@ -41,7 +41,7 @@
     "name": "LilyGo T-Beam supreme (8MB Flash 8MB PSRAM)",
     "upload": {
       "flash_size": "8MB",
-      "maximum_ram_size": 327680,
+      "maximum_ram_size": 8388608,
       "maximum_size": 8388608,
       "require_upload_port": true,
       "speed": 460800

examples/companion_radio/DataStore.cpp

@@ -222,12 +222,14 @@ void DataStore::loadPrefsInt(const char *filename, NodePrefs& _prefs, double& no
     file.read((uint8_t *)&_prefs.rx_delay_base, sizeof(_prefs.rx_delay_base));             // 72
     file.read((uint8_t *)&_prefs.advert_loc_policy, sizeof(_prefs.advert_loc_policy));     // 76
     file.read((uint8_t *)&_prefs.multi_acks, sizeof(_prefs.multi_acks));                   // 77
-    file.read(pad, 2);                                                                     // 78
+    file.read((uint8_t *)&_prefs.path_hash_mode, sizeof(_prefs.path_hash_mode));           // 78
+    file.read(pad, 1);                                                                     // 79
     file.read((uint8_t *)&_prefs.ble_pin, sizeof(_prefs.ble_pin));                         // 80
     file.read((uint8_t *)&_prefs.buzzer_quiet, sizeof(_prefs.buzzer_quiet));               // 84
     file.read((uint8_t *)&_prefs.gps_enabled, sizeof(_prefs.gps_enabled));                 // 85
     file.read((uint8_t *)&_prefs.gps_interval, sizeof(_prefs.gps_interval));               // 86
     file.read((uint8_t *)&_prefs.autoadd_config, sizeof(_prefs.autoadd_config));           // 87
+    file.read((uint8_t *)&_prefs.autoadd_max_hops, sizeof(_prefs.autoadd_max_hops));       // 88
 
     file.close();
   }
@@ -257,12 +259,14 @@ void DataStore::savePrefs(const NodePrefs& _prefs, double node_lat, double node_
     file.write((uint8_t *)&_prefs.rx_delay_base, sizeof(_prefs.rx_delay_base));             // 72
     file.write((uint8_t *)&_prefs.advert_loc_policy, sizeof(_prefs.advert_loc_policy));     // 76
     file.write((uint8_t *)&_prefs.multi_acks, sizeof(_prefs.multi_acks));                   // 77
-    file.write(pad, 2);                                                                     // 78
+    file.write((uint8_t *)&_prefs.path_hash_mode, sizeof(_prefs.path_hash_mode));           // 78
+    file.write(pad, 1);                                                                     // 79
     file.write((uint8_t *)&_prefs.ble_pin, sizeof(_prefs.ble_pin));                         // 80
     file.write((uint8_t *)&_prefs.buzzer_quiet, sizeof(_prefs.buzzer_quiet));               // 84
     file.write((uint8_t *)&_prefs.gps_enabled, sizeof(_prefs.gps_enabled));                 // 85
     file.write((uint8_t *)&_prefs.gps_interval, sizeof(_prefs.gps_interval));               // 86
     file.write((uint8_t *)&_prefs.autoadd_config, sizeof(_prefs.autoadd_config));           // 87
+    file.write((uint8_t *)&_prefs.autoadd_max_hops, sizeof(_prefs.autoadd_max_hops));      // 88
 
     file.close();
   }

examples/companion_radio/MyMesh.cpp

@@ -57,6 +57,7 @@
 #define CMD_SET_AUTOADD_CONFIG        58
 #define CMD_GET_AUTOADD_CONFIG        59
 #define CMD_GET_ALLOWED_REPEAT_FREQ   60
+#define CMD_SET_PATH_HASH_MODE        61
 
 // Stats sub-types for CMD_GET_STATS
 #define STATS_TYPE_CORE               0
@@ -258,11 +259,11 @@ int MyMesh::calcRxDelay(float score, uint32_t air_time) const {
 }
 
 uint32_t MyMesh::getRetransmitDelay(const mesh::Packet *packet) {
-  uint32_t t = (_radio->getEstAirtimeFor(packet->path_len + packet->payload_len + 2) * 0.5f);
+  uint32_t t = (_radio->getEstAirtimeFor(packet->getPathByteLen() + packet->payload_len + 2) * 0.5f);
   return getRNG()->nextInt(0, 5*t + 1);
 }
 uint32_t MyMesh::getDirectRetransmitDelay(const mesh::Packet *packet) {
-  uint32_t t = (_radio->getEstAirtimeFor(packet->path_len + packet->payload_len + 2) * 0.2f);
+  uint32_t t = (_radio->getEstAirtimeFor(packet->getPathByteLen() + packet->payload_len + 2) * 0.2f);
   return getRNG()->nextInt(0, 5*t + 1);
 }
 
@@ -317,6 +318,10 @@ bool MyMesh::shouldOverwriteWhenFull() const {
   return (_prefs.autoadd_config & AUTO_ADD_OVERWRITE_OLDEST) != 0;
 }
 
+uint8_t MyMesh::getAutoAddMaxHops() const {
+  return _prefs.autoadd_max_hops;
+}
+
 void MyMesh::onContactOverwrite(const uint8_t* pub_key) {
     _store->deleteBlobByKey(pub_key, PUB_KEY_SIZE); // delete from storage
   if (_serial->isConnected()) {
@@ -349,7 +354,7 @@ void MyMesh::onDiscoveredContact(ContactInfo &contact, bool is_new, uint8_t path
   }
 
   // add inbound-path to mem cache
-  if (path && path_len <= sizeof(AdvertPath::path)) {  // check path is valid
+  if (path && mesh::Packet::isValidPathLen(path_len)) {  // check path is valid
     AdvertPath* p = advert_paths;
     uint32_t oldest = 0xFFFFFFFF;
     for (int i = 0; i < ADVERT_PATH_TABLE_SIZE; i++) {   // check if already in table, otherwise evict oldest
@@ -366,8 +371,7 @@ void MyMesh::onDiscoveredContact(ContactInfo &contact, bool is_new, uint8_t path
     memcpy(p->pubkey_prefix, contact.id.pub_key, sizeof(p->pubkey_prefix));
     strcpy(p->name, contact.name);
     p->recv_timestamp = getRTCClock()->getCurrentTime();
-    p->path_len = path_len;
+    p->path_len = mesh::Packet::copyPath(p->path, path, path_len);
-    memcpy(p->path, path, p->path_len);
   }
 
   if (!is_new) dirty_contacts_expiry = futureMillis(LAZY_CONTACTS_WRITE_DELAY); // only schedule lazy write for contacts that are in contacts[]
@@ -473,23 +477,23 @@ bool MyMesh::allowPacketForward(const mesh::Packet* packet) {
 void MyMesh::sendFloodScoped(const ContactInfo& recipient, mesh::Packet* pkt, uint32_t delay_millis) {
   // TODO: dynamic send_scope, depending on recipient and current 'home' Region
   if (send_scope.isNull()) {
-    sendFlood(pkt, delay_millis);
+    sendFlood(pkt, delay_millis, _prefs.path_hash_mode + 1);
   } else {
     uint16_t codes[2];
     codes[0] = send_scope.calcTransportCode(pkt);
     codes[1] = 0;  // REVISIT: set to 'home' Region, for sender/return region?
-    sendFlood(pkt, codes, delay_millis);
+    sendFlood(pkt, codes, delay_millis, _prefs.path_hash_mode + 1);
   }
 }
 void MyMesh::sendFloodScoped(const mesh::GroupChannel& channel, mesh::Packet* pkt, uint32_t delay_millis) {
   // TODO: have per-channel send_scope
   if (send_scope.isNull()) {
-    sendFlood(pkt, delay_millis);
+    sendFlood(pkt, delay_millis, _prefs.path_hash_mode + 1);
   } else {
     uint16_t codes[2];
     codes[0] = send_scope.calcTransportCode(pkt);
     codes[1] = 0;  // REVISIT: set to 'home' Region, for sender/return region?
-    sendFlood(pkt, codes, delay_millis);
+    sendFlood(pkt, codes, delay_millis, _prefs.path_hash_mode + 1);
   }
 }
 
@@ -686,7 +690,7 @@ bool MyMesh::onContactPathRecv(ContactInfo& contact, uint8_t* in_path, uint8_t i
     if (tag == pending_discovery) {  // check for matching response tag)
       pending_discovery = 0;
 
-      if (in_path_len > MAX_PATH_SIZE || out_path_len > MAX_PATH_SIZE) {
+      if (!mesh::Packet::isValidPathLen(in_path_len) || !mesh::Packet::isValidPathLen(out_path_len)) {
         MESH_DEBUG_PRINTLN("onContactPathRecv, invalid path sizes: %d, %d", in_path_len, out_path_len);
       } else {
         int i = 0;
@@ -695,11 +699,9 @@ bool MyMesh::onContactPathRecv(ContactInfo& contact, uint8_t* in_path, uint8_t i
         memcpy(&out_frame[i], contact.id.pub_key, 6);
         i += 6; // pub_key_prefix
         out_frame[i++] = out_path_len;
-        memcpy(&out_frame[i], out_path, out_path_len);
+        i += mesh::Packet::writePath(&out_frame[i], out_path, out_path_len);
-        i += out_path_len;
         out_frame[i++] = in_path_len;
-        memcpy(&out_frame[i], in_path, in_path_len);
+        i += mesh::Packet::writePath(&out_frame[i], in_path, in_path_len);
-        i += in_path_len;
         // NOTE: telemetry data in 'extra' is discarded at present
 
         _serial->writeFrame(out_frame, i);
@@ -785,9 +787,10 @@ uint32_t MyMesh::calcFloodTimeoutMillisFor(uint32_t pkt_airtime_millis) const {
   return SEND_TIMEOUT_BASE_MILLIS + (FLOOD_SEND_TIMEOUT_FACTOR * pkt_airtime_millis);
 }
 uint32_t MyMesh::calcDirectTimeoutMillisFor(uint32_t pkt_airtime_millis, uint8_t path_len) const {
+  uint8_t path_hash_count = path_len & 63;
   return SEND_TIMEOUT_BASE_MILLIS +
          ((pkt_airtime_millis * DIRECT_SEND_PERHOP_FACTOR + DIRECT_SEND_PERHOP_EXTRA_MILLIS) *
-          (path_len + 1));
+          (path_hash_count + 1));
 }
 
 void MyMesh::onSendTimeout() {}
@@ -808,7 +811,7 @@ MyMesh::MyMesh(mesh::Radio &radio, mesh::RNG &rng, mesh::RTCClock &rtc, SimpleMe
 
   // defaults
   memset(&_prefs, 0, sizeof(_prefs));
-  _prefs.airtime_factor = 1.0; // one half
+  _prefs.airtime_factor = 1.0;
   strcpy(_prefs.node_name, "NONAME");
   _prefs.freq = LORA_FREQ;
   _prefs.sf = LORA_SF;
@@ -938,6 +941,7 @@ void MyMesh::handleCmdFrame(size_t len) {
     StrHelper::strzcpy((char *)&out_frame[i], FIRMWARE_VERSION, 20);
     i += 20;
     out_frame[i++] = _prefs.client_repeat;   // v9+
+    out_frame[i++] = _prefs.path_hash_mode;  // v10+
     _serial->writeFrame(out_frame, i);
   } else if (cmd_frame[0] == CMD_APP_START &&
              len >= 8) { // sent when app establishes connection, respond with node ID
@@ -1115,7 +1119,8 @@ void MyMesh::handleCmdFrame(size_t len) {
     }
     if (pkt) {
       if (len >= 2 && cmd_frame[1] == 1) { // optional param (1 = flood, 0 = zero hop)
-        sendFlood(pkt);
+        unsigned long delay_millis = 0;
+        sendFlood(pkt, delay_millis, _prefs.path_hash_mode + 1);
       } else {
         sendZeroHop(pkt);
       }
@@ -1127,7 +1132,7 @@ void MyMesh::handleCmdFrame(size_t len) {
     uint8_t *pub_key = &cmd_frame[1];
     ContactInfo *recipient = lookupContactByPubKey(pub_key, PUB_KEY_SIZE);
     if (recipient) {
-      recipient->out_path_len = -1;
+      recipient->out_path_len = OUT_PATH_UNKNOWN;
       // recipient->lastmod = ??   shouldn't be needed, app already has this version of contact
       dirty_contacts_expiry = futureMillis(LAZY_CONTACTS_WRITE_DELAY);
       writeOKFrame();
@@ -1312,6 +1317,14 @@ void MyMesh::handleCmdFrame(size_t len) {
     }
     savePrefs();
     writeOKFrame();
+  } else if (cmd_frame[0] == CMD_SET_PATH_HASH_MODE && cmd_frame[1] == 0 && len >= 3) {
+    if (cmd_frame[2] >= 3) {
+      writeErrFrame(ERR_CODE_ILLEGAL_ARG);
+    } else {
+      _prefs.path_hash_mode = cmd_frame[2];
+      savePrefs();
+      writeOKFrame();
+    }
   } else if (cmd_frame[0] == CMD_REBOOT && memcmp(&cmd_frame[1], "reboot", 6) == 0) {
     if (dirty_contacts_expiry) { // is there are pending dirty contacts write needed?
       saveContacts();
@@ -1449,7 +1462,7 @@ void MyMesh::handleCmdFrame(size_t len) {
       memset(&req_data[2], 0, 3);  // reserved
       getRNG()->random(&req_data[5], 4);   // random blob to help make packet-hash unique
       auto save = recipient->out_path_len;    // temporarily force sendRequest() to flood
-      recipient->out_path_len = -1;
+      recipient->out_path_len = OUT_PATH_UNKNOWN;
       int result = sendRequest(*recipient, req_data, sizeof(req_data), tag, est_timeout);
       recipient->out_path_len = save;
       if (result == MSG_SEND_FAILED) {
@@ -1686,11 +1699,12 @@ void MyMesh::handleCmdFrame(size_t len) {
       }
     }
     if (found) {
-      out_frame[0] = RESP_CODE_ADVERT_PATH;
+      int i = 0;
-      memcpy(&out_frame[1], &found->recv_timestamp, 4);
+      out_frame[i++] = RESP_CODE_ADVERT_PATH;
-      out_frame[5] = found->path_len;
+      memcpy(&out_frame[i], &found->recv_timestamp, 4); i += 4;
-      memcpy(&out_frame[6], found->path, found->path_len);
+      out_frame[i++] = found->path_len;
-      _serial->writeFrame(out_frame, 6 + found->path_len);
+      i += mesh::Packet::writePath(&out_frame[i], found->path, found->path_len);
+      _serial->writeFrame(out_frame, i);
     } else {
       writeErrFrame(ERR_CODE_NOT_FOUND);
     }
@@ -1775,12 +1789,16 @@ void MyMesh::handleCmdFrame(size_t len) {
     }
   } else if (cmd_frame[0] == CMD_SET_AUTOADD_CONFIG) {
     _prefs.autoadd_config = cmd_frame[1];
+    if (len >= 3) {
+      _prefs.autoadd_max_hops = min(cmd_frame[2], (uint8_t)64);
+    }
     savePrefs();
-    writeOKFrame();  
+    writeOKFrame();
   } else if (cmd_frame[0] == CMD_GET_AUTOADD_CONFIG) {
     int i = 0;
     out_frame[i++] = RESP_CODE_AUTOADD_CONFIG;
     out_frame[i++] = _prefs.autoadd_config;
+    out_frame[i++] = _prefs.autoadd_max_hops;
     _serial->writeFrame(out_frame, i);
   } else if (cmd_frame[0] == CMD_GET_ALLOWED_REPEAT_FREQ) {
     int i = 0;

examples/companion_radio/MyMesh.h

@@ -5,7 +5,7 @@
 #include "AbstractUITask.h"
 
 /*------------ Frame Protocol --------------*/
-#define FIRMWARE_VER_CODE 9
+#define FIRMWARE_VER_CODE 10
 
 #ifndef FIRMWARE_BUILD_DATE
 #define FIRMWARE_BUILD_DATE "15 Feb 2026"
@@ -119,6 +119,7 @@ protected:
   bool isAutoAddEnabled() const override;
   bool shouldAutoAddContactType(uint8_t type) const override;
   bool shouldOverwriteWhenFull() const override;
+  uint8_t getAutoAddMaxHops() const override;
   void onContactsFull() override;
   void onContactOverwrite(const uint8_t* pub_key) override;
   bool onContactPathRecv(ContactInfo& from, uint8_t* in_path, uint8_t in_path_len, uint8_t* out_path, uint8_t out_path_len, uint8_t extra_type, uint8_t* extra, uint8_t extra_len) override;

examples/companion_radio/NodePrefs.h

@@ -29,4 +29,6 @@ struct NodePrefs {  // persisted to file
   uint32_t gps_interval;     // GPS read interval in seconds
   uint8_t autoadd_config;    // bitmask for auto-add contacts config
   uint8_t client_repeat;
+  uint8_t path_hash_mode;    // which path mode to use when sending
+  uint8_t autoadd_max_hops;  // 0 = no limit, 1 = direct (0 hops), N = up to N-1 hops (max 64)
 };

examples/simple_repeater/MyMesh.cpp

@@ -129,7 +129,7 @@ uint8_t MyMesh::handleLoginReq(const mesh::Identity& sender, const uint8_t* secr
   }
 
   if (is_flood) {
-    client->out_path_len = -1;  // need to rediscover out_path
+    client->out_path_len = OUT_PATH_UNKNOWN;  // need to rediscover out_path
   }
 
   uint32_t now = getRTCClock()->getCurrentTimeUnique();
@@ -147,9 +147,12 @@ uint8_t MyMesh::handleLoginReq(const mesh::Identity& sender, const uint8_t* secr
 uint8_t MyMesh::handleAnonRegionsReq(const mesh::Identity& sender, uint32_t sender_timestamp, const uint8_t* data) {
   if (anon_limiter.allow(rtc_clock.getCurrentTime())) {
     // request data has: {reply-path-len}{reply-path}
-    reply_path_len = *data++ & 0x3F;
+    reply_path_len = *data & 63;
-    memcpy(reply_path, data, reply_path_len);
+    reply_path_hash_size = (*data >> 6) + 1;
-    // data += reply_path_len;
+    data++;
+
+    memcpy(reply_path, data, ((uint8_t)reply_path_len) * reply_path_hash_size);
+    // data += (uint8_t)reply_path_len * reply_path_hash_size;
 
     memcpy(reply_data, &sender_timestamp, 4);   // prefix with sender_timestamp, like a tag
     uint32_t now = getRTCClock()->getCurrentTime();
@@ -163,9 +166,12 @@ uint8_t MyMesh::handleAnonRegionsReq(const mesh::Identity& sender, uint32_t send
 uint8_t MyMesh::handleAnonOwnerReq(const mesh::Identity& sender, uint32_t sender_timestamp, const uint8_t* data) {
   if (anon_limiter.allow(rtc_clock.getCurrentTime())) {
     // request data has: {reply-path-len}{reply-path}
-    reply_path_len = *data++ & 0x3F;
+    reply_path_len = *data & 63;
-    memcpy(reply_path, data, reply_path_len);
+    reply_path_hash_size = (*data >> 6) + 1;
-    // data += reply_path_len;
+    data++;
+
+    memcpy(reply_path, data, ((uint8_t)reply_path_len) * reply_path_hash_size);
+    // data += (uint8_t)reply_path_len * reply_path_hash_size;
 
     memcpy(reply_data, &sender_timestamp, 4);   // prefix with sender_timestamp, like a tag
     uint32_t now = getRTCClock()->getCurrentTime();
@@ -180,9 +186,12 @@ uint8_t MyMesh::handleAnonOwnerReq(const mesh::Identity& sender, uint32_t sender
 uint8_t MyMesh::handleAnonClockReq(const mesh::Identity& sender, uint32_t sender_timestamp, const uint8_t* data) {
   if (anon_limiter.allow(rtc_clock.getCurrentTime())) {
     // request data has: {reply-path-len}{reply-path}
-    reply_path_len = *data++ & 0x3F;
+    reply_path_len = *data & 63;
-    memcpy(reply_path, data, reply_path_len);
+    reply_path_hash_size = (*data >> 6) + 1;
-    // data += reply_path_len;
+    data++;
+
+    memcpy(reply_path, data, ((uint8_t)reply_path_len) * reply_path_hash_size);
+    // data += (uint8_t)reply_path_len * reply_path_hash_size;
 
     memcpy(reply_data, &sender_timestamp, 4);   // prefix with sender_timestamp, like a tag
     uint32_t now = getRTCClock()->getCurrentTime();
@@ -389,11 +398,19 @@ File MyMesh::openAppend(const char *fname) {
 
 bool MyMesh::allowPacketForward(const mesh::Packet *packet) {
   if (_prefs.disable_fwd) return false;
-  if (packet->isRouteFlood() && packet->path_len >= _prefs.flood_max) return false;
+  if (packet->isRouteFlood() && packet->getPathHashCount() >= _prefs.flood_max) return false;
   if (packet->isRouteFlood() && recv_pkt_region == NULL) {
     MESH_DEBUG_PRINTLN("allowPacketForward: unknown transport code, or wildcard not allowed for FLOOD packet");
     return false;
   }
+  // Limit flood advert paket forwarding using a probabilistic reduction defined by P(h) = 0.308^(hops-1)
+  // https://github.com/meshcore-dev/MeshCore/issues/1223
+  double_t roll_dice = (double)rand() / RAND_MAX;
+  double_t forw_prob = pow(_prefs.flood_advert_base, packet->path_len - 1);
+  if (packet->getPayloadType() == PAYLOAD_TYPE_ADVERT && packet->isRouteFlood() && roll_dice > forw_prob)
+    return false;
+
+  // all other packets
   return true;
 }
 
@@ -484,11 +501,11 @@ int MyMesh::calcRxDelay(float score, uint32_t air_time) const {
 }
 
 uint32_t MyMesh::getRetransmitDelay(const mesh::Packet *packet) {
-  uint32_t t = (_radio->getEstAirtimeFor(packet->path_len + packet->payload_len + 2) * _prefs.tx_delay_factor);
+  uint32_t t = (_radio->getEstAirtimeFor(packet->getPathByteLen() + packet->payload_len + 2) * _prefs.tx_delay_factor);
   return getRNG()->nextInt(0, 5*t + 1);
 }
 uint32_t MyMesh::getDirectRetransmitDelay(const mesh::Packet *packet) {
-  uint32_t t = (_radio->getEstAirtimeFor(packet->path_len + packet->payload_len + 2) * _prefs.direct_tx_delay_factor);
+  uint32_t t = (_radio->getEstAirtimeFor(packet->getPathByteLen() + packet->payload_len + 2) * _prefs.direct_tx_delay_factor);
   return getRNG()->nextInt(0, 5*t + 1);
 }
 
@@ -497,7 +514,10 @@ bool MyMesh::filterRecvFloodPacket(mesh::Packet* pkt) {
   if (pkt->getRouteType() == ROUTE_TYPE_TRANSPORT_FLOOD) {
     recv_pkt_region = region_map.findMatch(pkt, REGION_DENY_FLOOD);
   } else if (pkt->getRouteType() == ROUTE_TYPE_FLOOD) {
-    if (region_map.getWildcard().flags & REGION_DENY_FLOOD) {
+      if ((pkt->getPayloadType() == PAYLOAD_TYPE_GRP_TXT ||
+           pkt->getPayloadType() == PAYLOAD_TYPE_GRP_DATA ||
+           pkt->getPayloadType() == PAYLOAD_TYPE_ADVERT) &&
+          region_map.getWildcard().flags & REGION_DENY_FLOOD) {
       recv_pkt_region = NULL;
     } else {
       recv_pkt_region =  &region_map.getWildcard();
@@ -538,13 +558,14 @@ void MyMesh::onAnonDataRecv(mesh::Packet *packet, const uint8_t *secret, const m
       // let this sender know path TO here, so they can use sendDirect(), and ALSO encode the response
       mesh::Packet* path = createPathReturn(sender, secret, packet->path, packet->path_len,
                                             PAYLOAD_TYPE_RESPONSE, reply_data, reply_len);
-      if (path) sendFlood(path, SERVER_RESPONSE_DELAY);
+      if (path) sendFlood(path, SERVER_RESPONSE_DELAY, packet->getPathHashSize());
     } else if (reply_path_len < 0) {
       mesh::Packet* reply = createDatagram(PAYLOAD_TYPE_RESPONSE, sender, secret, reply_data, reply_len);
-      if (reply) sendFlood(reply, SERVER_RESPONSE_DELAY);
+      if (reply) sendFlood(reply, SERVER_RESPONSE_DELAY, packet->getPathHashSize());
     } else {
       mesh::Packet* reply = createDatagram(PAYLOAD_TYPE_RESPONSE, sender, secret, reply_data, reply_len);
-      if (reply) sendDirect(reply, reply_path, reply_path_len, SERVER_RESPONSE_DELAY);
+      uint8_t path_len = ((reply_path_hash_size - 1) << 6) | (reply_path_len & 63);
+      if (reply) sendDirect(reply, reply_path,  path_len, SERVER_RESPONSE_DELAY);
     }
   }
 }
@@ -613,15 +634,15 @@ void MyMesh::onPeerDataRecv(mesh::Packet *packet, uint8_t type, int sender_idx,
         // let this sender know path TO here, so they can use sendDirect(), and ALSO encode the response
         mesh::Packet *path = createPathReturn(client->id, secret, packet->path, packet->path_len,
                                               PAYLOAD_TYPE_RESPONSE, reply_data, reply_len);
-        if (path) sendFlood(path, SERVER_RESPONSE_DELAY);
+        if (path) sendFlood(path, SERVER_RESPONSE_DELAY, packet->getPathHashSize());
       } else {
         mesh::Packet *reply =
             createDatagram(PAYLOAD_TYPE_RESPONSE, client->id, secret, reply_data, reply_len);
         if (reply) {
-          if (client->out_path_len >= 0) { // we have an out_path, so send DIRECT
+          if (client->out_path_len != OUT_PATH_UNKNOWN) { // we have an out_path, so send DIRECT
             sendDirect(reply, client->out_path, client->out_path_len, SERVER_RESPONSE_DELAY);
           } else {
-            sendFlood(reply, SERVER_RESPONSE_DELAY);
+            sendFlood(reply, SERVER_RESPONSE_DELAY, packet->getPathHashSize());
           }
         }
       }
@@ -651,8 +672,8 @@ void MyMesh::onPeerDataRecv(mesh::Packet *packet, uint8_t type, int sender_idx,
 
         mesh::Packet *ack = createAck(ack_hash);
         if (ack) {
-          if (client->out_path_len < 0) {
+          if (client->out_path_len == OUT_PATH_UNKNOWN) {
-            sendFlood(ack, TXT_ACK_DELAY);
+            sendFlood(ack, TXT_ACK_DELAY, packet->getPathHashSize());
           } else {
             sendDirect(ack, client->out_path, client->out_path_len, TXT_ACK_DELAY);
           }
@@ -679,8 +700,8 @@ void MyMesh::onPeerDataRecv(mesh::Packet *packet, uint8_t type, int sender_idx,
 
         auto reply = createDatagram(PAYLOAD_TYPE_TXT_MSG, client->id, secret, temp, 5 + text_len);
         if (reply) {
-          if (client->out_path_len < 0) {
+          if (client->out_path_len == OUT_PATH_UNKNOWN) {
-            sendFlood(reply, CLI_REPLY_DELAY_MILLIS);
+            sendFlood(reply, CLI_REPLY_DELAY_MILLIS, packet->getPathHashSize());
           } else {
             sendDirect(reply, client->out_path, client->out_path_len, CLI_REPLY_DELAY_MILLIS);
           }
@@ -701,7 +722,8 @@ bool MyMesh::onPeerPathRecv(mesh::Packet *packet, int sender_idx, const uint8_t
     MESH_DEBUG_PRINTLN("PATH to client, path_len=%d", (uint32_t)path_len);
     auto client = acl.getClientByIdx(i);
 
-    memcpy(client->out_path, path, client->out_path_len = path_len); // store a copy of path, for sendDirect()
+    // store a copy of path, for sendDirect()
+    client->out_path_len = mesh::Packet::copyPath(client->out_path, path, path_len);
     client->last_activity = getRTCClock()->getCurrentTime();
   } else {
     MESH_DEBUG_PRINTLN("onPeerPathRecv: invalid peer idx: %d", i);
@@ -813,7 +835,7 @@ MyMesh::MyMesh(mesh::MainBoard &board, mesh::Radio &radio, mesh::MillisecondCloc
 
   // defaults
   memset(&_prefs, 0, sizeof(_prefs));
-  _prefs.airtime_factor = 1.0;   // one half
+  _prefs.airtime_factor = 1.0;
   _prefs.rx_delay_base = 0.0f;   // turn off by default, was 10.0;
   _prefs.tx_delay_factor = 0.5f; // was 0.25f
   _prefs.direct_tx_delay_factor = 0.3f; // was 0.2
@@ -827,7 +849,8 @@ MyMesh::MyMesh(mesh::MainBoard &board, mesh::Radio &radio, mesh::MillisecondCloc
   _prefs.cr = LORA_CR;
   _prefs.tx_power_dbm = LORA_TX_POWER;
   _prefs.advert_interval = 1;        // default to 2 minutes for NEW installs
-  _prefs.flood_advert_interval = 12; // 12 hours
+  _prefs.flood_advert_interval = 0; // 12 hours
+  _prefs.flood_advert_base = 0.308f;
   _prefs.flood_max = 64;
   _prefs.interference_threshold = 0; // disabled
 
@@ -906,7 +929,7 @@ void MyMesh::sendSelfAdvertisement(int delay_millis, bool flood) {
   mesh::Packet *pkt = createSelfAdvert();
   if (pkt) {
     if (flood) {
-      sendFlood(pkt, delay_millis);
+      sendFlood(pkt, delay_millis, _prefs.path_hash_mode + 1);
     } else {
       sendZeroHop(pkt, delay_millis);
     }

examples/simple_repeater/MyMesh.h

@@ -92,6 +92,7 @@ class MyMesh : public mesh::Mesh, public CommonCLICallbacks {
   uint8_t reply_data[MAX_PACKET_PAYLOAD];
   uint8_t reply_path[MAX_PATH_SIZE];
   int8_t  reply_path_len;
+  uint8_t reply_path_hash_size;
   TransportKeyStore key_store;
   RegionMap region_map, temp_map;
   RegionEntry* load_stack[8];

examples/simple_room_server/MyMesh.cpp

@@ -73,13 +73,15 @@ void MyMesh::pushPostToClient(ClientInfo *client, PostInfo &post) {
 
   auto reply = createDatagram(PAYLOAD_TYPE_TXT_MSG, client->id, client->shared_secret, reply_data, len);
   if (reply) {
-    if (client->out_path_len < 0) {
+    if (client->out_path_len == OUT_PATH_UNKNOWN) {
-      sendFlood(reply);
+      unsigned long delay_millis = 0;
+      sendFlood(reply, delay_millis, _prefs.path_hash_mode + 1);
       client->extra.room.ack_timeout = futureMillis(PUSH_ACK_TIMEOUT_FLOOD);
     } else {
       sendDirect(reply, client->out_path, client->out_path_len);
-      client->extra.room.ack_timeout =
+
-          futureMillis(PUSH_TIMEOUT_BASE + PUSH_ACK_TIMEOUT_FACTOR * (client->out_path_len + 1));
+      uint8_t path_hash_count = client->out_path_len & 63;
+      client->extra.room.ack_timeout = futureMillis(PUSH_TIMEOUT_BASE + PUSH_ACK_TIMEOUT_FACTOR * (path_hash_count + 1));
     }
     _num_post_pushes++; // stats
   } else {
@@ -264,17 +266,26 @@ const char *MyMesh::getLogDateTime() {
 }
 
 uint32_t MyMesh::getRetransmitDelay(const mesh::Packet *packet) {
-  uint32_t t = (_radio->getEstAirtimeFor(packet->path_len + packet->payload_len + 2) * _prefs.tx_delay_factor);
+  uint32_t t = (_radio->getEstAirtimeFor(packet->getPathByteLen() + packet->payload_len + 2) * _prefs.tx_delay_factor);
   return getRNG()->nextInt(0, 5*t + 1);
 }
 uint32_t MyMesh::getDirectRetransmitDelay(const mesh::Packet *packet) {
-  uint32_t t = (_radio->getEstAirtimeFor(packet->path_len + packet->payload_len + 2) * _prefs.direct_tx_delay_factor);
+  uint32_t t = (_radio->getEstAirtimeFor(packet->getPathByteLen() + packet->payload_len + 2) * _prefs.direct_tx_delay_factor);
   return getRNG()->nextInt(0, 5*t + 1);
 }
 
 bool MyMesh::allowPacketForward(const mesh::Packet *packet) {
   if (_prefs.disable_fwd) return false;
-  if (packet->isRouteFlood() && packet->path_len >= _prefs.flood_max) return false;
+  if (packet->isRouteFlood() && packet->getPathHashCount() >= _prefs.flood_max) return false;
+
+  // Limit flood advert paket forwarding using a probabilistic reduction defined by P(h) = 0.308^(hops-1)
+  // https://github.com/meshcore-dev/MeshCore/issues/1223
+  double_t roll_dice = (double)rand() / RAND_MAX;
+  double_t forw_prob = pow(_prefs.flood_advert_base, packet->path_len - 1);
+  if (packet->getPayloadType() == PAYLOAD_TYPE_ADVERT && packet->isRouteFlood() && roll_dice > forw_prob)
+    return false;
+
+  // all other packets
   return true;
 }
 
@@ -333,7 +344,7 @@ void MyMesh::onAnonDataRecv(mesh::Packet *packet, const uint8_t *secret, const m
     }
 
     if (packet->isRouteFlood()) {
-      client->out_path_len = -1;  // need to rediscover out_path
+      client->out_path_len = OUT_PATH_UNKNOWN;  // need to rediscover out_path
     }
 
     uint32_t now = getRTCClock()->getCurrentTimeUnique();
@@ -353,14 +364,14 @@ void MyMesh::onAnonDataRecv(mesh::Packet *packet, const uint8_t *secret, const m
       // let this sender know path TO here, so they can use sendDirect(), and ALSO encode the response
       mesh::Packet *path = createPathReturn(sender, client->shared_secret, packet->path, packet->path_len,
                                             PAYLOAD_TYPE_RESPONSE, reply_data, 13);
-      if (path) sendFlood(path, SERVER_RESPONSE_DELAY);
+      if (path) sendFlood(path, SERVER_RESPONSE_DELAY, packet->getPathHashSize());
     } else {
       mesh::Packet *reply = createDatagram(PAYLOAD_TYPE_RESPONSE, sender, client->shared_secret, reply_data, 13);
       if (reply) {
-        if (client->out_path_len >= 0) { // we have an out_path, so send DIRECT
+        if (client->out_path_len != OUT_PATH_UNKNOWN) { // we have an out_path, so send DIRECT
           sendDirect(reply, client->out_path, client->out_path_len, SERVER_RESPONSE_DELAY);
         } else {
-          sendFlood(reply, SERVER_RESPONSE_DELAY);
+          sendFlood(reply, SERVER_RESPONSE_DELAY, packet->getPathHashSize());
         }
       }
     }
@@ -448,9 +459,9 @@ void MyMesh::onPeerDataRecv(mesh::Packet *packet, uint8_t type, int sender_idx,
 
       uint32_t delay_millis;
       if (send_ack) {
-        if (client->out_path_len < 0) {
+        if (client->out_path_len == OUT_PATH_UNKNOWN) {
           mesh::Packet *ack = createAck(ack_hash);
-          if (ack) sendFlood(ack, TXT_ACK_DELAY);
+          if (ack) sendFlood(ack, TXT_ACK_DELAY, packet->getPathHashSize());
           delay_millis = TXT_ACK_DELAY + REPLY_DELAY_MILLIS;
         } else {
           uint32_t d = TXT_ACK_DELAY;
@@ -482,8 +493,8 @@ void MyMesh::onPeerDataRecv(mesh::Packet *packet, uint8_t type, int sender_idx,
 
         auto reply = createDatagram(PAYLOAD_TYPE_TXT_MSG, client->id, secret, temp, 5 + text_len);
         if (reply) {
-          if (client->out_path_len < 0) {
+          if (client->out_path_len == OUT_PATH_UNKNOWN) {
-            sendFlood(reply, delay_millis + SERVER_RESPONSE_DELAY);
+            sendFlood(reply, delay_millis + SERVER_RESPONSE_DELAY, packet->getPathHashSize());
           } else {
             sendDirect(reply, client->out_path, client->out_path_len, delay_millis + SERVER_RESPONSE_DELAY);
           }
@@ -521,7 +532,7 @@ void MyMesh::onPeerDataRecv(mesh::Packet *packet, uint8_t type, int sender_idx,
         // if client sends too quickly, evict()
 
         // RULE: only send keep_alive response DIRECT!
-        if (client->out_path_len >= 0) {
+        if (client->out_path_len != OUT_PATH_UNKNOWN) {
           uint32_t ack_hash; // calc ACK to prove to sender that we got request
           mesh::Utils::sha256((uint8_t *)&ack_hash, 4, data, 9, client->id.pub_key, PUB_KEY_SIZE);
 
@@ -538,14 +549,14 @@ void MyMesh::onPeerDataRecv(mesh::Packet *packet, uint8_t type, int sender_idx,
             // let this sender know path TO here, so they can use sendDirect(), and ALSO encode the response
             mesh::Packet *path = createPathReturn(client->id, secret, packet->path, packet->path_len,
                                                   PAYLOAD_TYPE_RESPONSE, reply_data, reply_len);
-            if (path) sendFlood(path, SERVER_RESPONSE_DELAY);
+            if (path) sendFlood(path, SERVER_RESPONSE_DELAY, packet->getPathHashSize());
           } else {
             mesh::Packet *reply = createDatagram(PAYLOAD_TYPE_RESPONSE, client->id, secret, reply_data, reply_len);
             if (reply) {
-              if (client->out_path_len >= 0) { // we have an out_path, so send DIRECT
+              if (client->out_path_len != OUT_PATH_UNKNOWN) { // we have an out_path, so send DIRECT
                 sendDirect(reply, client->out_path, client->out_path_len, SERVER_RESPONSE_DELAY);
               } else {
-                sendFlood(reply, SERVER_RESPONSE_DELAY);
+                sendFlood(reply, SERVER_RESPONSE_DELAY, packet->getPathHashSize());
               }
             }
           }
@@ -563,7 +574,7 @@ bool MyMesh::onPeerPathRecv(mesh::Packet *packet, int sender_idx, const uint8_t
   if (i >= 0 && i < acl.getNumClients()) { // get from our known_clients table (sender SHOULD already be known in this context)
     MESH_DEBUG_PRINTLN("PATH to client, path_len=%d", (uint32_t)path_len);
     auto client = acl.getClientByIdx(i);
-    memcpy(client->out_path, path, client->out_path_len = path_len); // store a copy of path, for sendDirect()
+    client->out_path_len = mesh::Packet::copyPath(client->out_path, path, path_len); // store a copy of path, for sendDirect()
     client->last_activity = getRTCClock()->getCurrentTime();
   } else {
     MESH_DEBUG_PRINTLN("onPeerPathRecv: invalid peer idx: %d", i);
@@ -597,7 +608,7 @@ MyMesh::MyMesh(mesh::MainBoard &board, mesh::Radio &radio, mesh::MillisecondCloc
 
   // defaults
   memset(&_prefs, 0, sizeof(_prefs));
-  _prefs.airtime_factor = 1.0;   // one half
+  _prefs.airtime_factor = 1.0;
   _prefs.rx_delay_base = 0.0f;   // off by default, was 10.0
   _prefs.tx_delay_factor = 0.5f; // was 0.25f;
   _prefs.direct_tx_delay_factor = 0.2f; // was zero
@@ -612,7 +623,8 @@ MyMesh::MyMesh(mesh::MainBoard &board, mesh::Radio &radio, mesh::MillisecondCloc
   _prefs.tx_power_dbm = LORA_TX_POWER;
   _prefs.disable_fwd = 1;
   _prefs.advert_interval = 1;        // default to 2 minutes for NEW installs
-  _prefs.flood_advert_interval = 12; // 12 hours
+  _prefs.flood_advert_interval = 0; // 12 hours
+  _prefs.flood_advert_base = 0.308f;
   _prefs.flood_max = 64;
   _prefs.interference_threshold = 0; // disabled
 #ifdef ROOM_PASSWORD
@@ -679,7 +691,7 @@ void MyMesh::sendSelfAdvertisement(int delay_millis, bool flood) {
   mesh::Packet *pkt = createSelfAdvert();
   if (pkt) {
     if (flood) {
-      sendFlood(pkt, delay_millis);
+      sendFlood(pkt, delay_millis, _prefs.path_hash_mode + 1);
     } else {
       sendZeroHop(pkt, delay_millis);
     }

examples/simple_secure_chat/main.cpp

@@ -213,7 +213,7 @@ protected:
   }
 
   void onContactPathUpdated(const ContactInfo& contact) override {
-    Serial.printf("PATH to: %s, path_len=%d\n", contact.name, (int32_t) contact.out_path_len);
+    Serial.printf("PATH to: %s, path_len=%d\n", contact.name, (uint32_t) contact.out_path_len);
     saveContacts();
   }
 
@@ -266,8 +266,9 @@ protected:
     return SEND_TIMEOUT_BASE_MILLIS + (FLOOD_SEND_TIMEOUT_FACTOR * pkt_airtime_millis);
   }
   uint32_t calcDirectTimeoutMillisFor(uint32_t pkt_airtime_millis, uint8_t path_len) const override {
+    uint8_t path_hash_count = path_len & 63;
     return SEND_TIMEOUT_BASE_MILLIS + 
-         ( (pkt_airtime_millis*DIRECT_SEND_PERHOP_FACTOR + DIRECT_SEND_PERHOP_EXTRA_MILLIS) * (path_len + 1));
+         ( (pkt_airtime_millis*DIRECT_SEND_PERHOP_FACTOR + DIRECT_SEND_PERHOP_EXTRA_MILLIS) * (path_hash_count + 1));
   }
 
   void onSendTimeout() override {
@@ -280,7 +281,7 @@ public:
   {
     // defaults
     memset(&_prefs, 0, sizeof(_prefs));
-    _prefs.airtime_factor = 2.0;    // one third
+    _prefs.airtime_factor = 1.0;
     strcpy(_prefs.node_name, "NONAME");
     _prefs.freq = LORA_FREQ;
     _prefs.tx_power_dbm = LORA_TX_POWER;

examples/simple_sensor/SensorMesh.cpp

@@ -258,10 +258,11 @@ void SensorMesh::sendAlert(const ClientInfo* c, Trigger* t) {
 
   auto pkt = createDatagram(PAYLOAD_TYPE_TXT_MSG, c->id, c->shared_secret, data, 5 + text_len);
   if (pkt) {
-    if (c->out_path_len >= 0) {  // we have an out_path, so send DIRECT
+    if (c->out_path_len != OUT_PATH_UNKNOWN) {  // we have an out_path, so send DIRECT
       sendDirect(pkt, c->out_path, c->out_path_len);
     } else {
-      sendFlood(pkt);
+      unsigned long delay_millis = 0;
+      sendFlood(pkt, delay_millis, _prefs.path_hash_mode + 1);
     }
   }
   t->send_expiry = futureMillis(ALERT_ACK_EXPIRY_MILLIS);
@@ -302,7 +303,7 @@ float SensorMesh::getAirtimeBudgetFactor() const {
 
 bool SensorMesh::allowPacketForward(const mesh::Packet* packet) {
   if (_prefs.disable_fwd) return false;
-  if (packet->isRouteFlood() && packet->path_len >= _prefs.flood_max) return false;
+  if (packet->isRouteFlood() && packet->getPathHashCount() >= _prefs.flood_max) return false;
   return true;
 }
 
@@ -312,11 +313,11 @@ int SensorMesh::calcRxDelay(float score, uint32_t air_time) const {
 }
 
 uint32_t SensorMesh::getRetransmitDelay(const mesh::Packet* packet) {
-  uint32_t t = (_radio->getEstAirtimeFor(packet->path_len + packet->payload_len + 2) * _prefs.tx_delay_factor);
+  uint32_t t = (_radio->getEstAirtimeFor(packet->getPathByteLen() + packet->payload_len + 2) * _prefs.tx_delay_factor);
   return getRNG()->nextInt(0, 6)*t;
 }
 uint32_t SensorMesh::getDirectRetransmitDelay(const mesh::Packet* packet) {
-  uint32_t t = (_radio->getEstAirtimeFor(packet->path_len + packet->payload_len + 2) * _prefs.direct_tx_delay_factor);
+  uint32_t t = (_radio->getEstAirtimeFor(packet->getPathByteLen() + packet->payload_len + 2) * _prefs.direct_tx_delay_factor);
   return getRNG()->nextInt(0, 6)*t;
 }
 int SensorMesh::getInterferenceThreshold() const {
@@ -360,7 +361,7 @@ uint8_t SensorMesh::handleLoginReq(const mesh::Identity& sender, const uint8_t*
   }
 
   if (is_flood) {
-    client->out_path_len = -1;  // need to rediscover out_path
+    client->out_path_len = OUT_PATH_UNKNOWN;  // need to rediscover out_path
   }
 
   uint32_t now = getRTCClock()->getCurrentTimeUnique();
@@ -468,10 +469,10 @@ void SensorMesh::onAnonDataRecv(mesh::Packet* packet, const uint8_t* secret, con
       // let this sender know path TO here, so they can use sendDirect(), and ALSO encode the response
       mesh::Packet* path = createPathReturn(sender, secret, packet->path, packet->path_len,
                                             PAYLOAD_TYPE_RESPONSE, reply_data, reply_len);
-      if (path) sendFlood(path, SERVER_RESPONSE_DELAY);
+      if (path) sendFlood(path, SERVER_RESPONSE_DELAY, packet->getPathHashSize());
     } else {
       mesh::Packet* reply = createDatagram(PAYLOAD_TYPE_RESPONSE, sender, secret, reply_data, reply_len);
-      if (reply) sendFlood(reply, SERVER_RESPONSE_DELAY);
+      if (reply) sendFlood(reply, SERVER_RESPONSE_DELAY, packet->getPathHashSize());
     }
   }
 }
@@ -496,10 +497,10 @@ void SensorMesh::getPeerSharedSecret(uint8_t* dest_secret, int peer_idx) {
   }
 }
 
-void SensorMesh::sendAckTo(const ClientInfo& dest, uint32_t ack_hash) {
+void SensorMesh::sendAckTo(const ClientInfo& dest, uint32_t ack_hash, uint8_t path_hash_size) {
-  if (dest.out_path_len < 0) {
+  if (dest.out_path_len == OUT_PATH_UNKNOWN) {
     mesh::Packet* ack = createAck(ack_hash);
-    if (ack) sendFlood(ack, TXT_ACK_DELAY);
+    if (ack) sendFlood(ack, TXT_ACK_DELAY, path_hash_size);
   } else {
     uint32_t d = TXT_ACK_DELAY;
     if (getExtraAckTransmitCount() > 0) {
@@ -537,14 +538,14 @@ void SensorMesh::onPeerDataRecv(mesh::Packet* packet, uint8_t type, int sender_i
         // let this sender know path TO here, so they can use sendDirect(), and ALSO encode the response
         mesh::Packet* path = createPathReturn(from->id, secret, packet->path, packet->path_len,
                                               PAYLOAD_TYPE_RESPONSE, reply_data, reply_len);
-        if (path) sendFlood(path, SERVER_RESPONSE_DELAY);
+        if (path) sendFlood(path, SERVER_RESPONSE_DELAY, packet->getPathHashSize());
       } else {
         mesh::Packet* reply = createDatagram(PAYLOAD_TYPE_RESPONSE, from->id, secret, reply_data, reply_len);
         if (reply) {
-          if (from->out_path_len >= 0) {  // we have an out_path, so send DIRECT
+          if (from->out_path_len != OUT_PATH_UNKNOWN) {  // we have an out_path, so send DIRECT
             sendDirect(reply, from->out_path, from->out_path_len, SERVER_RESPONSE_DELAY);
           } else {
-            sendFlood(reply, SERVER_RESPONSE_DELAY);
+            sendFlood(reply, SERVER_RESPONSE_DELAY, packet->getPathHashSize());
           }
         }
       }
@@ -567,9 +568,9 @@ void SensorMesh::onPeerDataRecv(mesh::Packet* packet, uint8_t type, int sender_i
             // let this sender know path TO here, so they can use sendDirect(), and ALSO encode the ACK
             mesh::Packet* path = createPathReturn(from->id, secret, packet->path, packet->path_len,
                                                   PAYLOAD_TYPE_ACK, (uint8_t *) &ack_hash, 4);
-            if (path) sendFlood(path, TXT_ACK_DELAY);
+            if (path) sendFlood(path, TXT_ACK_DELAY, packet->getPathHashSize());
           } else {
-            sendAckTo(*from, ack_hash);
+            sendAckTo(*from, ack_hash, packet->getPathHashSize());
           }
         }
       } else if (flags == TXT_TYPE_CLI_DATA) {  
@@ -596,8 +597,8 @@ void SensorMesh::onPeerDataRecv(mesh::Packet* packet, uint8_t type, int sender_i
 
           auto reply = createDatagram(PAYLOAD_TYPE_TXT_MSG, from->id, secret, temp, 5 + text_len);
           if (reply) {
-            if (from->out_path_len < 0) {
+            if (from->out_path_len == OUT_PATH_UNKNOWN) {
-              sendFlood(reply, CLI_REPLY_DELAY_MILLIS);
+              sendFlood(reply, CLI_REPLY_DELAY_MILLIS, packet->getPathHashSize());
             } else {
               sendDirect(reply, from->out_path, from->out_path_len, CLI_REPLY_DELAY_MILLIS);
             }
@@ -666,7 +667,7 @@ bool SensorMesh::onPeerPathRecv(mesh::Packet* packet, int sender_idx, const uint
   MESH_DEBUG_PRINTLN("PATH to contact, path_len=%d", (uint32_t) path_len);
   // NOTE: for this impl, we just replace the current 'out_path' regardless, whenever sender sends us a new out_path.
   // FUTURE: could store multiple out_paths per contact, and try to find which is the 'best'(?)
-  memcpy(from->out_path, path, from->out_path_len = path_len);  // store a copy of path, for sendDirect()
+  from->out_path_len = mesh::Packet::copyPath(from->out_path, path, path_len);  // store a copy of path, for sendDirect()
   from->last_activity = getRTCClock()->getCurrentTime();
 
   // REVISIT: maybe make ALL out_paths non-persisted to minimise flash writes??
@@ -705,7 +706,7 @@ SensorMesh::SensorMesh(mesh::MainBoard& board, mesh::Radio& radio, mesh::Millise
 
   // defaults
   memset(&_prefs, 0, sizeof(_prefs));
-  _prefs.airtime_factor = 1.0;    // one half
+  _prefs.airtime_factor = 1.0;
   _prefs.rx_delay_base =   0.0f;  // turn off by default, was 10.0;
   _prefs.tx_delay_factor = 0.5f;   // was 0.25f
   _prefs.direct_tx_delay_factor = 0.2f; // was zero
@@ -791,7 +792,7 @@ void SensorMesh::sendSelfAdvertisement(int delay_millis, bool flood) {
   mesh::Packet* pkt = createSelfAdvert();
   if (pkt) {
     if (flood) {
-      sendFlood(pkt, delay_millis);
+      sendFlood(pkt, delay_millis, _prefs.path_hash_mode + 1);
     } else {
       sendZeroHop(pkt, delay_millis);
     }
@@ -868,7 +869,8 @@ void SensorMesh::loop() {
 
   if (next_flood_advert && millisHasNowPassed(next_flood_advert)) {
     mesh::Packet* pkt = createSelfAdvert();
-    if (pkt) sendFlood(pkt);
+    unsigned long delay_millis = 0;
+    if (pkt) sendFlood(pkt, delay_millis, _prefs.path_hash_mode + 1);
 
     updateFloodAdvertTimer();   // schedule next flood advert
     updateAdvertTimer();   // also schedule local advert (so they don't overlap)

examples/simple_sensor/SensorMesh.h

@@ -128,7 +128,7 @@ protected:
   void onControlDataRecv(mesh::Packet* packet) override;
   void onAckRecv(mesh::Packet* packet, uint32_t ack_crc) override;
   virtual bool handleIncomingMsg(ClientInfo& from, uint32_t timestamp, uint8_t* data, uint8_t flags, size_t len);
-  void sendAckTo(const ClientInfo& dest, uint32_t ack_hash);
+  void sendAckTo(const ClientInfo& dest, uint32_t ack_hash, uint8_t path_hash_size=1);
 private:
   FILESYSTEM* _fs;
   unsigned long next_local_advert, next_flood_advert;

platformio.ini

@@ -24,9 +24,9 @@ lib_deps =
   melopero/Melopero RV3028 @ ^1.1.0
   electroniccats/CayenneLPP @ 1.6.1
 build_flags = -w -DNDEBUG -DRADIOLIB_STATIC_ONLY=1 -DRADIOLIB_GODMODE=1
-  -D LORA_FREQ=869.525
+  -D LORA_FREQ=869.618
-  -D LORA_BW=250
+  -D LORA_BW=62.5
-  -D LORA_SF=11
+  -D LORA_SF=8
   -D ENABLE_ADVERT_ON_BOOT=1
   -D ENABLE_PRIVATE_KEY_IMPORT=1   ; NOTE: comment these out for more secure firmware
   -D ENABLE_PRIVATE_KEY_EXPORT=1

src/Dispatcher.cpp

@@ -8,7 +8,9 @@
 
 namespace mesh {
 
-#define MAX_RX_DELAY_MILLIS   32000  // 32 seconds
+#define MAX_RX_DELAY_MILLIS        32000  // 32 seconds
+#define MIN_TX_BUDGET_RESERVE_MS   100    // min budget (ms) required before allowing next TX
+#define MIN_TX_BUDGET_AIRTIME_DIV  2      // require at least 1/N of estimated airtime as budget before TX
 
 #ifndef NOISE_FLOOR_CALIB_INTERVAL
   #define NOISE_FLOOR_CALIB_INTERVAL   2000     // 2 seconds
@@ -20,12 +22,34 @@ void Dispatcher::begin() {
   _err_flags = 0;
   radio_nonrx_start = _ms->getMillis();
 
+  duty_cycle_window_ms = getDutyCycleWindowMs();
+  float duty_cycle = 1.0f / (1.0f + getAirtimeBudgetFactor());
+  tx_budget_ms = (unsigned long)(duty_cycle_window_ms * duty_cycle);
+  last_budget_update = _ms->getMillis();
+
   _radio->begin();
   prev_isrecv_mode = _radio->isInRecvMode();
 }
 
 float Dispatcher::getAirtimeBudgetFactor() const {
-  return 2.0;   // default, 33.3%  (1/3rd)
+  return 1.0;
+}
+
+void Dispatcher::updateTxBudget() {
+  unsigned long now = _ms->getMillis();
+  unsigned long elapsed = now - last_budget_update;
+
+  float duty_cycle = 1.0f / (1.0f + getAirtimeBudgetFactor());
+  unsigned long max_budget = (unsigned long)(getDutyCycleWindowMs() * duty_cycle);
+  unsigned long refill = (unsigned long)(elapsed * duty_cycle);
+  
+  if (refill > 0) {
+    tx_budget_ms += refill;
+    if (tx_budget_ms > max_budget) {
+      tx_budget_ms = max_budget;
+    }
+    last_budget_update = now;
+  }
 }
 
 int Dispatcher::calcRxDelay(float score, uint32_t air_time) const {
@@ -61,14 +85,27 @@ void Dispatcher::loop() {
   if (outbound) {  // waiting for outbound send to be completed
     if (_radio->isSendComplete()) {
       long t = _ms->getMillis() - outbound_start;
-      total_air_time += t;  // keep track of how much air time we are using
+      total_air_time += t;
       //Serial.print("  airtime="); Serial.println(t);
 
-      // will need radio silence up to next_tx_time
+      updateTxBudget();
-      next_tx_time = futureMillis(t * getAirtimeBudgetFactor());
+
+      if (t > tx_budget_ms) {
+        tx_budget_ms = 0;
+      } else {
+        tx_budget_ms -= t;
+      }
+
+      if (tx_budget_ms < MIN_TX_BUDGET_RESERVE_MS) {
+        float duty_cycle = 1.0f / (1.0f + getAirtimeBudgetFactor());
+        unsigned long needed = MIN_TX_BUDGET_RESERVE_MS - tx_budget_ms;
+        next_tx_time = futureMillis((unsigned long)(needed / duty_cycle));
+      } else {
+        next_tx_time = _ms->getMillis();
+      }
 
       _radio->onSendFinished();
-      logTx(outbound, 2 + outbound->path_len + outbound->payload_len);
+      logTx(outbound, 2 + outbound->getPathByteLen() + outbound->payload_len);
       if (outbound->isRouteFlood()) {
         n_sent_flood++;
       } else {
@@ -80,7 +117,7 @@ void Dispatcher::loop() {
       MESH_DEBUG_PRINTLN("%s Dispatcher::loop(): WARNING: outbound packed send timed out!", getLogDateTime());
 
       _radio->onSendFinished();
-      logTxFail(outbound, 2 + outbound->path_len + outbound->payload_len);
+      logTxFail(outbound, 2 + outbound->getPathByteLen() + outbound->payload_len);
 
       releasePacket(outbound);  // return to pool
       outbound = NULL;
@@ -108,6 +145,48 @@ void Dispatcher::loop() {
   checkSend();
 }
 
+bool Dispatcher::tryParsePacket(Packet* pkt, const uint8_t* raw, int len) {
+  int i = 0;
+
+  pkt->header = raw[i++];
+  if (pkt->getPayloadVer() > PAYLOAD_VER_1) {
+    MESH_DEBUG_PRINTLN("%s Dispatcher::checkRecv(): unsupported packet version", getLogDateTime());
+    return false;
+  }
+
+  if (pkt->hasTransportCodes()) {
+    memcpy(&pkt->transport_codes[0], &raw[i], 2); i += 2;
+    memcpy(&pkt->transport_codes[1], &raw[i], 2); i += 2;
+  } else {
+    pkt->transport_codes[0] = pkt->transport_codes[1] = 0;
+  }
+
+  pkt->path_len = raw[i++];
+  uint8_t path_mode = pkt->path_len >> 6;  // upper 2 bits (legacy firmware: 00)
+  if (path_mode == 3) {   // Reserved for future
+    MESH_DEBUG_PRINTLN("%s Dispatcher::checkRecv(): unsupported path mode: 3", getLogDateTime());
+    return false;
+  }
+
+  uint8_t path_byte_len = (pkt->path_len & 63) * pkt->getPathHashSize();
+  if (path_byte_len > MAX_PATH_SIZE || i + path_byte_len > len) {
+    MESH_DEBUG_PRINTLN("%s Dispatcher::checkRecv(): partial or corrupt packet received, len=%d", getLogDateTime(), len);
+    return false;
+  }
+
+  memcpy(pkt->path, &raw[i], path_byte_len); i += path_byte_len;
+
+  pkt->payload_len = len - i;  // payload is remainder
+  if (pkt->payload_len > sizeof(pkt->payload)) {
+    MESH_DEBUG_PRINTLN("%s Dispatcher::checkRecv(): packet payload too big, payload_len=%d", getLogDateTime(), (uint32_t)pkt->payload_len);
+    return false;
+  }
+
+  memcpy(pkt->payload, &raw[i], pkt->payload_len);
+
+  return true;  // success
+}
+
 void Dispatcher::checkRecv() {
   Packet* pkt;
   float score;
@@ -122,45 +201,14 @@ void Dispatcher::checkRecv() {
       if (pkt == NULL) {
         MESH_DEBUG_PRINTLN("%s Dispatcher::checkRecv(): WARNING: received data, no unused packets available!", getLogDateTime());
       } else {
-        int i = 0;
+        if (tryParsePacket(pkt, raw, len)) {
-#ifdef NODE_ID
+          pkt->_snr = _radio->getLastSNR() * 4.0f;
-        uint8_t sender_id = raw[i++];
+          score = _radio->packetScore(_radio->getLastSNR(), len);
-        if (sender_id == NODE_ID - 1 || sender_id == NODE_ID + 1) {  // simulate that NODE_ID can only hear NODE_ID-1 or NODE_ID+1, eg. 3 can't hear 1
+          air_time = _radio->getEstAirtimeFor(len);
+          rx_air_time += air_time;
         } else {
-          _mgr->free(pkt);  // put back into pool
-          return;
-        }
-#endif
-
-        pkt->header = raw[i++];
-        if (pkt->hasTransportCodes()) {
-          memcpy(&pkt->transport_codes[0], &raw[i], 2); i += 2;
-          memcpy(&pkt->transport_codes[1], &raw[i], 2); i += 2;
-        } else {
-          pkt->transport_codes[0] = pkt->transport_codes[1] = 0;
-        }
-        pkt->path_len = raw[i++];
-
-        if (pkt->path_len > MAX_PATH_SIZE || i + pkt->path_len > len) {
-          MESH_DEBUG_PRINTLN("%s Dispatcher::checkRecv(): partial or corrupt packet received, len=%d", getLogDateTime(), len);
           _mgr->free(pkt);  // put back into pool
           pkt = NULL;
-        } else {
-          memcpy(pkt->path, &raw[i], pkt->path_len); i += pkt->path_len;
-
-          pkt->payload_len = len - i;  // payload is remainder
-          if (pkt->payload_len > sizeof(pkt->payload)) {
-            MESH_DEBUG_PRINTLN("%s Dispatcher::checkRecv(): packet payload too big, payload_len=%d", getLogDateTime(), (uint32_t)pkt->payload_len);
-            _mgr->free(pkt);  // put back into pool
-            pkt = NULL;  
-          } else {
-            memcpy(pkt->payload, &raw[i], pkt->payload_len);
-
-            pkt->_snr = _radio->getLastSNR() * 4.0f;
-            score = _radio->packetScore(_radio->getLastSNR(), len);
-            air_time = _radio->getEstAirtimeFor(len);
-            rx_air_time += air_time;
-          }
         }
       }
     } else {
@@ -224,9 +272,20 @@ void Dispatcher::processRecvPacket(Packet* pkt) {
 }
 
 void Dispatcher::checkSend() {
-  if (_mgr->getOutboundCount(_ms->getMillis()) == 0) return;  // nothing waiting to send
+  if (_mgr->getOutboundCount(_ms->getMillis()) == 0) return;
-  if (!millisHasNowPassed(next_tx_time)) return;   // still in 'radio silence' phase (from airtime budget setting)
+  
-  if (_radio->isReceiving()) {   // LBT - check if radio is currently mid-receive, or if channel activity
+  updateTxBudget();
+  
+  uint32_t est_airtime = _radio->getEstAirtimeFor(MAX_TRANS_UNIT);
+  if (tx_budget_ms < est_airtime / MIN_TX_BUDGET_AIRTIME_DIV) {
+    float duty_cycle = 1.0f / (1.0f + getAirtimeBudgetFactor());
+    unsigned long needed = est_airtime / MIN_TX_BUDGET_AIRTIME_DIV - tx_budget_ms;
+    next_tx_time = futureMillis((unsigned long)(needed / duty_cycle));
+    return;
+  }
+  
+  if (!millisHasNowPassed(next_tx_time)) return;
+  if (_radio->isReceiving()) {
     if (cad_busy_start == 0) {
       cad_busy_start = _ms->getMillis();   // record when CAD busy state started
     }
@@ -249,16 +308,13 @@ void Dispatcher::checkSend() {
     int len = 0;
     uint8_t raw[MAX_TRANS_UNIT];
 
-#ifdef NODE_ID
-    raw[len++] = NODE_ID;
-#endif
     raw[len++] = outbound->header;
     if (outbound->hasTransportCodes()) {
       memcpy(&raw[len], &outbound->transport_codes[0], 2); len += 2;
       memcpy(&raw[len], &outbound->transport_codes[1], 2); len += 2;
     }
     raw[len++] = outbound->path_len;
-    memcpy(&raw[len], outbound->path, outbound->path_len); len += outbound->path_len;
+    len += Packet::writePath(&raw[len], outbound->path, outbound->path_len);
 
     if (len + outbound->payload_len > MAX_TRANS_UNIT) {
       MESH_DEBUG_PRINTLN("%s Dispatcher::checkSend(): FATAL: Invalid packet queued... too long, len=%d", getLogDateTime(), len + outbound->payload_len);
@@ -312,7 +368,7 @@ void Dispatcher::releasePacket(Packet* packet) {
 }
 
 void Dispatcher::sendPacket(Packet* packet, uint8_t priority, uint32_t delay_millis) {
-  if (packet->path_len > MAX_PATH_SIZE || packet->payload_len > MAX_PACKET_PAYLOAD) {
+  if (!Packet::isValidPathLen(packet->path_len) || packet->payload_len > MAX_PACKET_PAYLOAD) {
     MESH_DEBUG_PRINTLN("%s Dispatcher::sendPacket(): ERROR: invalid packet... path_len=%d, payload_len=%d", getLogDateTime(), (uint32_t) packet->path_len, (uint32_t) packet->payload_len);
     _mgr->free(packet);
   } else {

src/Dispatcher.h

@@ -122,8 +122,12 @@ class Dispatcher {
   bool  prev_isrecv_mode;
   uint32_t n_sent_flood, n_sent_direct;
   uint32_t n_recv_flood, n_recv_direct;
+  unsigned long tx_budget_ms;
+  unsigned long last_budget_update;
+  unsigned long duty_cycle_window_ms;
 
   void processRecvPacket(Packet* pkt);
+  void updateTxBudget();
 
 protected:
   PacketManager* _mgr;
@@ -142,6 +146,9 @@ protected:
     _err_flags = 0;
     radio_nonrx_start = 0;
     prev_isrecv_mode = true;
+    tx_budget_ms = 0;
+    last_budget_update = 0;
+    duty_cycle_window_ms = 3600000;
   }
 
   virtual DispatcherAction onRecvPacket(Packet* pkt) = 0;
@@ -159,6 +166,7 @@ protected:
   virtual uint32_t getCADFailMaxDuration() const;
   virtual int getInterferenceThreshold() const { return 0; }    // disabled by default
   virtual int getAGCResetInterval() const { return 0; }    // disabled by default
+  virtual unsigned long getDutyCycleWindowMs() const { return 3600000; }
 
 public:
   void begin();
@@ -168,8 +176,9 @@ public:
   void releasePacket(Packet* packet);
   void sendPacket(Packet* packet, uint8_t priority, uint32_t delay_millis=0);
 
-  unsigned long getTotalAirTime() const { return total_air_time; }  // in milliseconds
+  unsigned long getTotalAirTime() const { return total_air_time; }
   unsigned long getReceiveAirTime() const {return rx_air_time; }
+  unsigned long getRemainingTxBudget() const { return tx_budget_ms; }
   uint32_t getNumSentFlood() const { return n_sent_flood; }
   uint32_t getNumSentDirect() const { return n_sent_direct; }
   uint32_t getNumRecvFlood() const { return n_recv_flood; }
@@ -184,6 +193,7 @@ public:
   unsigned long futureMillis(int millis_from_now) const;
 
 private:
+  bool tryParsePacket(Packet* pkt, const uint8_t* raw, int len);
   void checkRecv();
   void checkSend();
 };

src/Identity.h

@@ -20,6 +20,10 @@ public:
     memcpy(dest, pub_key, PATH_HASH_SIZE);    // hash is just prefix of pub_key
     return PATH_HASH_SIZE;
   }
+  int copyHashTo(uint8_t* dest, uint8_t len) const { 
+    memcpy(dest, pub_key, len);    // hash is just prefix of pub_key
+    return len;
+  }
   bool isHashMatch(const uint8_t* hash) const {
     return memcmp(hash, pub_key, PATH_HASH_SIZE) == 0;
   }

src/Mesh.cpp

@@ -39,11 +39,6 @@ int Mesh::searchChannelsByHash(const uint8_t* hash, GroupChannel channels[], int
 }
 
 DispatcherAction Mesh::onRecvPacket(Packet* pkt) {
-  if (pkt->getPayloadVer() > PAYLOAD_VER_1) {  // not supported in this firmware version
-    MESH_DEBUG_PRINTLN("%s Mesh::onRecvPacket(): unsupported packet version", getLogDateTime());
-    return ACTION_RELEASE;
-  }
-
   if (pkt->isRouteDirect() && pkt->getPayloadType() == PAYLOAD_TYPE_TRACE) {
     if (pkt->path_len < MAX_PATH_SIZE) {
       uint8_t i = 0;
@@ -70,14 +65,14 @@ DispatcherAction Mesh::onRecvPacket(Packet* pkt) {
   }
 
   if (pkt->isRouteDirect() && pkt->getPayloadType() == PAYLOAD_TYPE_CONTROL && (pkt->payload[0] & 0x80) != 0) {
-    if (pkt->path_len == 0) {
+    if (pkt->getPathHashCount() == 0) {
       onControlDataRecv(pkt);
     }
     // just zero-hop control packets allowed (for this subset of payloads)
     return ACTION_RELEASE;
   }
 
-  if (pkt->isRouteDirect() && pkt->path_len >= PATH_HASH_SIZE) {
+  if (pkt->isRouteDirect() && pkt->getPathHashCount() > 0) {
     // check for 'early received' ACK
     if (pkt->getPayloadType() == PAYLOAD_TYPE_ACK) {
       int i = 0;
@@ -88,7 +83,7 @@ DispatcherAction Mesh::onRecvPacket(Packet* pkt) {
       }
     }
 
-    if (self_id.isHashMatch(pkt->path) && allowPacketForward(pkt)) {
+    if (self_id.isHashMatch(pkt->path, pkt->getPathHashSize()) && allowPacketForward(pkt)) {
       if (pkt->getPayloadType() == PAYLOAD_TYPE_MULTIPART) {
         return forwardMultipartDirect(pkt);
       } else if (pkt->getPayloadType() == PAYLOAD_TYPE_ACK) {
@@ -158,7 +153,9 @@ DispatcherAction Mesh::onRecvPacket(Packet* pkt) {
               if (pkt->getPayloadType() == PAYLOAD_TYPE_PATH) {
                 int k = 0;
                 uint8_t path_len = data[k++];
-                uint8_t* path = &data[k]; k += path_len;
+                uint8_t hash_size = (path_len >> 6) + 1;
+                uint8_t hash_count = path_len & 63;
+                uint8_t* path = &data[k]; k += hash_size*hash_count;
                 uint8_t extra_type = data[k++] & 0x0F;   // upper 4 bits reserved for future use
                 uint8_t* extra = &data[k];
                 uint8_t extra_len = len - k;   // remainder of packet (may be padded with zeroes!)
@@ -293,8 +290,7 @@ DispatcherAction Mesh::onRecvPacket(Packet* pkt) {
         if (type == PAYLOAD_TYPE_ACK && pkt->payload_len >= 5) {    // a multipart ACK
           Packet tmp;
           tmp.header = pkt->header;
-          tmp.path_len = pkt->path_len;
+          tmp.path_len = Packet::copyPath(tmp.path, pkt->path, pkt->path_len);
-          memcpy(tmp.path, pkt->path, pkt->path_len);
           tmp.payload_len = pkt->payload_len - 1;
           memcpy(tmp.payload, &pkt->payload[1], tmp.payload_len);
 
@@ -321,27 +317,25 @@ DispatcherAction Mesh::onRecvPacket(Packet* pkt) {
 
 void Mesh::removeSelfFromPath(Packet* pkt) {
   // remove our hash from 'path'
-  pkt->path_len -= PATH_HASH_SIZE;
+  pkt->setPathHashCount(pkt->getPathHashCount() - 1);  // decrement the count
-#if 0
+
-  memcpy(pkt->path, &pkt->path[PATH_HASH_SIZE], pkt->path_len);
+  uint8_t sz = pkt->getPathHashSize();
-#elif PATH_HASH_SIZE == 1
+  for (int k = 0; k < pkt->getPathHashCount()*sz; k += sz) {  // shuffle path by 1 'entry'
-  for (int k = 0; k < pkt->path_len; k++) {  // shuffle bytes by 1
+    memcpy(&pkt->path[k], &pkt->path[k + sz], sz);
-    pkt->path[k] = pkt->path[k + 1];
   }
-#else
-  #error "need path remove impl"
-#endif
 }
 
 DispatcherAction Mesh::routeRecvPacket(Packet* packet) {
+  uint8_t n = packet->getPathHashCount();
   if (packet->isRouteFlood() && !packet->isMarkedDoNotRetransmit()
-    && packet->path_len + PATH_HASH_SIZE <= MAX_PATH_SIZE && allowPacketForward(packet)) {
+    && (n + 1)*packet->getPathHashSize() <= MAX_PATH_SIZE && allowPacketForward(packet)) {
     // append this node's hash to 'path'
-    packet->path_len += self_id.copyHashTo(&packet->path[packet->path_len]);
+    self_id.copyHashTo(&packet->path[n * packet->getPathHashSize()], packet->getPathHashSize());
+    packet->setPathHashCount(n + 1);
 
     uint32_t d = getRetransmitDelay(packet);
     // as this propagates outwards, give it lower and lower priority
-    return ACTION_RETRANSMIT_DELAYED(packet->path_len, d);   // give priority to closer sources, than ones further away
+    return ACTION_RETRANSMIT_DELAYED(packet->getPathHashCount(), d);   // give priority to closer sources, than ones further away
   }
   return ACTION_RELEASE;
 }
@@ -353,8 +347,7 @@ DispatcherAction Mesh::forwardMultipartDirect(Packet* pkt) {
   if (type == PAYLOAD_TYPE_ACK && pkt->payload_len >= 5) {    // a multipart ACK
     Packet tmp;
     tmp.header = pkt->header;
-    tmp.path_len = pkt->path_len;
+    tmp.path_len = Packet::copyPath(tmp.path, pkt->path, pkt->path_len);
-    memcpy(tmp.path, pkt->path, pkt->path_len);
     tmp.payload_len = pkt->payload_len - 1;
     memcpy(tmp.payload, &pkt->payload[1], tmp.payload_len);
 
@@ -376,7 +369,7 @@ void Mesh::routeDirectRecvAcks(Packet* packet, uint32_t delay_millis) {
       delay_millis += getDirectRetransmitDelay(packet) + 300;
       auto a1 = createMultiAck(crc, extra);
       if (a1) {
-        memcpy(a1->path, packet->path, a1->path_len = packet->path_len);
+        a1->path_len = Packet::copyPath(a1->path, packet->path, packet->path_len);
         a1->header &= ~PH_ROUTE_MASK;
         a1->header |= ROUTE_TYPE_DIRECT;
         sendPacket(a1, 0, delay_millis);
@@ -386,7 +379,7 @@ void Mesh::routeDirectRecvAcks(Packet* packet, uint32_t delay_millis) {
 
     auto a2 = createAck(crc);
     if (a2) {
-      memcpy(a2->path, packet->path, a2->path_len = packet->path_len);
+      a2->path_len = Packet::copyPath(a2->path, packet->path, packet->path_len);
       a2->header &= ~PH_ROUTE_MASK;
       a2->header |= ROUTE_TYPE_DIRECT;
       sendPacket(a2, 0, delay_millis);
@@ -439,7 +432,10 @@ Packet* Mesh::createPathReturn(const Identity& dest, const uint8_t* secret, cons
 }
 
 Packet* Mesh::createPathReturn(const uint8_t* dest_hash, const uint8_t* secret, const uint8_t* path, uint8_t path_len, uint8_t extra_type, const uint8_t*extra, size_t extra_len) {
-  if (path_len + extra_len + 5 > MAX_COMBINED_PATH) return NULL;  // too long!!
+  uint8_t path_hash_size = (path_len >> 6) + 1;
+  uint8_t path_hash_count = path_len & 63;
+
+  if (path_hash_count*path_hash_size + extra_len + 5 > MAX_COMBINED_PATH) return NULL;  // too long!!
 
   Packet* packet = obtainNewPacket();
   if (packet == NULL) {
@@ -457,7 +453,7 @@ Packet* Mesh::createPathReturn(const uint8_t* dest_hash, const uint8_t* secret,
     uint8_t data[MAX_PACKET_PAYLOAD];
 
     data[data_len++] = path_len;
-    memcpy(&data[data_len], path, path_len); data_len += path_len;
+    memcpy(&data[data_len], path, path_hash_count*path_hash_size); data_len += path_hash_count*path_hash_size;
     if (extra_len > 0) {
       data[data_len++] = extra_type;
       memcpy(&data[data_len], extra, extra_len); data_len += extra_len;
@@ -624,15 +620,19 @@ Packet* Mesh::createControlData(const uint8_t* data, size_t len) {
   return packet;
 }
 
-void Mesh::sendFlood(Packet* packet, uint32_t delay_millis) {
+void Mesh::sendFlood(Packet* packet, uint32_t delay_millis, uint8_t path_hash_size) {
   if (packet->getPayloadType() == PAYLOAD_TYPE_TRACE) {
     MESH_DEBUG_PRINTLN("%s Mesh::sendFlood(): TRACE type not suspported", getLogDateTime());
     return;
   }
+  if (path_hash_size == 0 || path_hash_size > 3) {
+    MESH_DEBUG_PRINTLN("%s Mesh::sendFlood(): invalid path_hash_size", getLogDateTime());
+    return;
+  }
 
   packet->header &= ~PH_ROUTE_MASK;
   packet->header |= ROUTE_TYPE_FLOOD;
-  packet->path_len = 0;
+  packet->setPathHashSizeAndCount(path_hash_size, 0);
 
   _tables->hasSeen(packet); // mark this packet as already sent in case it is rebroadcast back to us
 
@@ -647,17 +647,21 @@ void Mesh::sendFlood(Packet* packet, uint32_t delay_millis) {
   sendPacket(packet, pri, delay_millis);
 }
 
-void Mesh::sendFlood(Packet* packet, uint16_t* transport_codes, uint32_t delay_millis) {
+void Mesh::sendFlood(Packet* packet, uint16_t* transport_codes, uint32_t delay_millis, uint8_t path_hash_size) {
   if (packet->getPayloadType() == PAYLOAD_TYPE_TRACE) {
     MESH_DEBUG_PRINTLN("%s Mesh::sendFlood(): TRACE type not suspported", getLogDateTime());
     return;
   }
+  if (path_hash_size == 0 || path_hash_size > 3) {
+    MESH_DEBUG_PRINTLN("%s Mesh::sendFlood(): invalid path_hash_size", getLogDateTime());
+    return;
+  }
 
   packet->header &= ~PH_ROUTE_MASK;
   packet->header |= ROUTE_TYPE_TRANSPORT_FLOOD;
   packet->transport_codes[0] = transport_codes[0];
   packet->transport_codes[1] = transport_codes[1];
-  packet->path_len = 0;
+  packet->setPathHashSizeAndCount(path_hash_size, 0);
 
   _tables->hasSeen(packet); // mark this packet as already sent in case it is rebroadcast back to us
 
@@ -679,13 +683,13 @@ void Mesh::sendDirect(Packet* packet, const uint8_t* path, uint8_t path_len, uin
   uint8_t pri;
   if (packet->getPayloadType() == PAYLOAD_TYPE_TRACE) {   // TRACE packets are different
     // for TRACE packets, path is appended to end of PAYLOAD. (path is used for SNR's)
-    memcpy(&packet->payload[packet->payload_len], path, path_len);
+    memcpy(&packet->payload[packet->payload_len], path, path_len);  // NOTE: path_len here can be > 64, and NOT in the new scheme
     packet->payload_len += path_len;
 
     packet->path_len = 0;
     pri = 5;   // maybe make this configurable
   } else {
-    memcpy(packet->path, path, packet->path_len = path_len);
+    packet->path_len = Packet::copyPath(packet->path, path, path_len);
     if (packet->getPayloadType() == PAYLOAD_TYPE_PATH) {
       pri = 1;   // slightly less priority
     } else {

src/Mesh.h

@@ -196,13 +196,13 @@ public:
   /**
    * \brief  send a locally-generated Packet with flood routing
   */
-  void sendFlood(Packet* packet, uint32_t delay_millis=0);
+  void sendFlood(Packet* packet, uint32_t delay_millis=0, uint8_t path_hash_size=1);
 
   /**
    * \brief  send a locally-generated Packet with flood routing
    * \param transport_codes   array of 2 codes to attach to packet
   */
-  void sendFlood(Packet* packet, uint16_t* transport_codes, uint32_t delay_millis=0);
+  void sendFlood(Packet* packet, uint16_t* transport_codes, uint32_t delay_millis=0, uint8_t path_hash_size=1);
 
   /**
    * \brief  send a locally-generated Packet with Direct routing

src/MeshCore.h

@@ -55,6 +55,7 @@ public:
   virtual uint32_t getGpio() { return 0; }
   virtual void setGpio(uint32_t values) {}
   virtual uint8_t getStartupReason() const = 0;
+  virtual bool getBootloaderVersion(char* version, size_t max_len) { return false; }
   virtual bool startOTAUpdate(const char* id, char reply[]) { return false; }   // not supported
 
   // Power management interface (boards with power management override these)

src/Packet.cpp

@@ -10,8 +10,32 @@ Packet::Packet() {
   payload_len = 0;
 }
 
+bool Packet::isValidPathLen(uint8_t path_len) {
+  uint8_t hash_count = path_len & 63;
+  uint8_t hash_size = (path_len >> 6) + 1;
+  if (hash_size == 4) return false;  // Reserved for future
+  return hash_count*hash_size <= MAX_PATH_SIZE;
+}
+
+size_t Packet::writePath(uint8_t* dest, const uint8_t* src, uint8_t path_len) {
+  uint8_t hash_count = path_len & 63;
+  uint8_t hash_size = (path_len >> 6) + 1;
+  size_t len = hash_count*hash_size;
+  if (len > MAX_PATH_SIZE) {
+    MESH_DEBUG_PRINTLN("Packet::copyPath, invalid path_len=%d", (uint32_t)path_len);
+    return 0;   // Error
+  }
+  memcpy(dest, src, len);
+  return len;
+}
+
+uint8_t Packet::copyPath(uint8_t* dest, const uint8_t* src, uint8_t path_len) {
+  writePath(dest, src, path_len);
+  return path_len;
+}
+
 int Packet::getRawLength() const {
-  return 2 + path_len + payload_len + (hasTransportCodes() ? 4 : 0);
+  return 2 + getPathByteLen() + payload_len + (hasTransportCodes() ? 4 : 0);
 }
 
 void Packet::calculatePacketHash(uint8_t* hash) const {
@@ -33,7 +57,7 @@ uint8_t Packet::writeTo(uint8_t dest[]) const {
     memcpy(&dest[i], &transport_codes[1], 2); i += 2;
   }
   dest[i++] = path_len;
-  memcpy(&dest[i], path, path_len); i += path_len;
+  i += writePath(&dest[i], path, path_len);
   memcpy(&dest[i], payload, payload_len); i += payload_len;
   return i;
 }
@@ -48,8 +72,11 @@ bool Packet::readFrom(const uint8_t src[], uint8_t len) {
     transport_codes[0] = transport_codes[1] = 0;
   }
   path_len = src[i++];
-  if (path_len > sizeof(path)) return false;   // bad encoding
+  if (!isValidPathLen(path_len)) return false;   // bad encoding
-  memcpy(path, &src[i], path_len); i += path_len;
+
+  uint8_t bl = getPathByteLen();
+  memcpy(path, &src[i], bl); i += bl;
+
   if (i >= len) return false;   // bad encoding
   payload_len = len - i;
   if (payload_len > sizeof(payload)) return false;  // bad encoding

src/Packet.h

@@ -76,6 +76,16 @@ public:
    */
   uint8_t getPayloadVer() const { return (header >> PH_VER_SHIFT) & PH_VER_MASK; }
 
+  uint8_t getPathHashSize() const { return (path_len >> 6) + 1; }
+  uint8_t getPathHashCount() const { return path_len & 63; }
+  uint8_t getPathByteLen() const { return getPathHashCount() * getPathHashSize(); }
+  void setPathHashCount(uint8_t n) { path_len &= ~63; path_len |= n; }
+  void setPathHashSizeAndCount(uint8_t sz, uint8_t n) { path_len = ((sz - 1) << 6) | (n & 63); }
+
+  static uint8_t copyPath(uint8_t* dest, const uint8_t* src, uint8_t path_len);  // returns path_len
+  static size_t writePath(uint8_t* dest, const uint8_t* src, uint8_t path_len);  // returns byte length written
+  static bool isValidPathLen(uint8_t path_len);
+
   void markDoNotRetransmit() { header = 0xFF; }
   bool isMarkedDoNotRetransmit() const { return header == 0xFF; }
 

src/helpers/BaseChatMesh.cpp

@@ -39,7 +39,7 @@ mesh::Packet* BaseChatMesh::createSelfAdvert(const char* name, double lat, doubl
 }
 
 void BaseChatMesh::sendAckTo(const ContactInfo& dest, uint32_t ack_hash) {
-  if (dest.out_path_len < 0) {
+  if (dest.out_path_len == OUT_PATH_UNKNOWN) {
     mesh::Packet* ack = createAck(ack_hash);
     if (ack) sendFloodScoped(dest, ack, TXT_ACK_DELAY);
   } else {
@@ -92,7 +92,7 @@ ContactInfo* BaseChatMesh::allocateContactSlot() {
 void BaseChatMesh::populateContactFromAdvert(ContactInfo& ci, const mesh::Identity& id, const AdvertDataParser& parser, uint32_t timestamp) {
   memset(&ci, 0, sizeof(ci));
   ci.id = id;
-  ci.out_path_len = -1;  // initially out_path is unknown
+  ci.out_path_len = OUT_PATH_UNKNOWN;
   StrHelper::strncpy(ci.name, parser.getName(), sizeof(ci.name));
   ci.type = parser.getType();
   if (parser.hasLatLon()) {
@@ -141,6 +141,15 @@ void BaseChatMesh::onAdvertRecv(mesh::Packet* packet, const mesh::Identity& id,
       return;
     }
 
+    // check hop limit for new contacts (0 = no limit, 1 = direct (0 hops), N = up to N-1 hops)
+    uint8_t max_hops = getAutoAddMaxHops();
+    if (max_hops > 0 && packet->getPathHashCount() >= max_hops) {
+      ContactInfo ci;
+      populateContactFromAdvert(ci, id, parser, timestamp);
+      onDiscoveredContact(ci, true, packet->path_len, packet->path);       // let UI know
+      return;
+    }
+
     from = allocateContactSlot();
     if (from == NULL) {
       ContactInfo ci;
@@ -263,7 +272,7 @@ void BaseChatMesh::onPeerDataRecv(mesh::Packet* packet, uint8_t type, int sender
       } else {
         mesh::Packet* reply = createDatagram(PAYLOAD_TYPE_RESPONSE, from.id, secret, temp_buf, reply_len);
         if (reply) {
-          if (from.out_path_len >= 0) {  // we have an out_path, so send DIRECT
+          if (from.out_path_len != OUT_PATH_UNKNOWN) {  // we have an out_path, so send DIRECT
             sendDirect(reply, from.out_path, from.out_path_len, SERVER_RESPONSE_DELAY);
           } else {
             sendFloodScoped(from, reply, SERVER_RESPONSE_DELAY);
@@ -273,7 +282,7 @@ void BaseChatMesh::onPeerDataRecv(mesh::Packet* packet, uint8_t type, int sender
     }
   } else if (type == PAYLOAD_TYPE_RESPONSE && len > 0) {
     onContactResponse(from, data, len);
-    if (packet->isRouteFlood() && from.out_path_len >= 0) {
+    if (packet->isRouteFlood() && from.out_path_len != OUT_PATH_UNKNOWN) {
       // we have direct path, but other node is still sending flood response, so maybe they didn't receive reciprocal path properly(?)
       handleReturnPathRetry(from, packet->path, packet->path_len);
     }
@@ -295,7 +304,7 @@ bool BaseChatMesh::onPeerPathRecv(mesh::Packet* packet, int sender_idx, const ui
 bool BaseChatMesh::onContactPathRecv(ContactInfo& from, uint8_t* in_path, uint8_t in_path_len, uint8_t* out_path, uint8_t out_path_len, uint8_t extra_type, uint8_t* extra, uint8_t extra_len) {
   // NOTE: default impl, we just replace the current 'out_path' regardless, whenever sender sends us a new out_path.
   // FUTURE: could store multiple out_paths per contact, and try to find which is the 'best'(?)
-  memcpy(from.out_path, out_path, from.out_path_len = out_path_len);  // store a copy of path, for sendDirect()
+  from.out_path_len = mesh::Packet::copyPath(from.out_path, out_path, out_path_len);  // store a copy of path, for sendDirect()
   from.lastmod = getRTCClock()->getCurrentTime();
 
   onContactPathUpdated(from);
@@ -317,7 +326,7 @@ void BaseChatMesh::onAckRecv(mesh::Packet* packet, uint32_t ack_crc) {
     txt_send_timeout = 0;   // matched one we're waiting for, cancel timeout timer
     packet->markDoNotRetransmit();   // ACK was for this node, so don't retransmit
 
-    if (packet->isRouteFlood() && from->out_path_len >= 0) {
+    if (packet->isRouteFlood() && from->out_path_len != OUT_PATH_UNKNOWN) {
       // we have direct path, but other node is still sending flood, so maybe they didn't receive reciprocal path properly(?)
       handleReturnPathRetry(*from, packet->path, packet->path_len);
     }
@@ -386,7 +395,7 @@ int  BaseChatMesh::sendMessage(const ContactInfo& recipient, uint32_t timestamp,
   uint32_t t = _radio->getEstAirtimeFor(pkt->getRawLength());
 
   int rc;
-  if (recipient.out_path_len < 0) {
+  if (recipient.out_path_len == OUT_PATH_UNKNOWN) {
     sendFloodScoped(recipient, pkt);
     txt_send_timeout = futureMillis(est_timeout = calcFloodTimeoutMillisFor(t));
     rc = MSG_SEND_SENT_FLOOD;
@@ -412,7 +421,7 @@ int  BaseChatMesh::sendCommandData(const ContactInfo& recipient, uint32_t timest
 
   uint32_t t = _radio->getEstAirtimeFor(pkt->getRawLength());
   int rc;
-  if (recipient.out_path_len < 0) {
+  if (recipient.out_path_len == OUT_PATH_UNKNOWN) {
     sendFloodScoped(recipient, pkt);
     txt_send_timeout = futureMillis(est_timeout = calcFloodTimeoutMillisFor(t));
     rc = MSG_SEND_SENT_FLOOD;
@@ -500,7 +509,7 @@ int BaseChatMesh::sendLogin(const ContactInfo& recipient, const char* password,
   }
   if (pkt) {
     uint32_t t = _radio->getEstAirtimeFor(pkt->getRawLength());
-    if (recipient.out_path_len < 0) {
+    if (recipient.out_path_len == OUT_PATH_UNKNOWN) {
       sendFloodScoped(recipient, pkt);
       est_timeout = calcFloodTimeoutMillisFor(t);
       return MSG_SEND_SENT_FLOOD;
@@ -525,7 +534,7 @@ int BaseChatMesh::sendAnonReq(const ContactInfo& recipient, const uint8_t* data,
   }
   if (pkt) {
     uint32_t t = _radio->getEstAirtimeFor(pkt->getRawLength());
-    if (recipient.out_path_len < 0) {
+    if (recipient.out_path_len == OUT_PATH_UNKNOWN) {
       sendFloodScoped(recipient, pkt);
       est_timeout = calcFloodTimeoutMillisFor(t);
       return MSG_SEND_SENT_FLOOD;
@@ -552,7 +561,7 @@ int  BaseChatMesh::sendRequest(const ContactInfo& recipient, const uint8_t* req_
   }
   if (pkt) {
     uint32_t t = _radio->getEstAirtimeFor(pkt->getRawLength());
-    if (recipient.out_path_len < 0) {
+    if (recipient.out_path_len == OUT_PATH_UNKNOWN) {
       sendFloodScoped(recipient, pkt);
       est_timeout = calcFloodTimeoutMillisFor(t);
       return MSG_SEND_SENT_FLOOD;
@@ -579,7 +588,7 @@ int  BaseChatMesh::sendRequest(const ContactInfo& recipient, uint8_t req_type, u
   }
   if (pkt) {
     uint32_t t = _radio->getEstAirtimeFor(pkt->getRawLength());
-    if (recipient.out_path_len < 0) {
+    if (recipient.out_path_len == OUT_PATH_UNKNOWN) {
       sendFloodScoped(recipient, pkt);
       est_timeout = calcFloodTimeoutMillisFor(t);
       return MSG_SEND_SENT_FLOOD;
@@ -683,7 +692,7 @@ void BaseChatMesh::checkConnections() {
         MESH_DEBUG_PRINTLN("checkConnections(): Keep_alive contact not found!");
         continue;
       }
-      if (contact->out_path_len < 0) {
+      if (contact->out_path_len == OUT_PATH_UNKNOWN) {
         MESH_DEBUG_PRINTLN("checkConnections(): Keep_alive contact, no out_path!");
         continue;
       }
@@ -710,7 +719,7 @@ void BaseChatMesh::checkConnections() {
 }
 
 void BaseChatMesh::resetPathTo(ContactInfo& recipient) {
-  recipient.out_path_len = -1;
+  recipient.out_path_len = OUT_PATH_UNKNOWN;
 }
 
 static ContactInfo* table;  // pass via global :-(

src/helpers/BaseChatMesh.h

@@ -98,6 +98,7 @@ protected:
   virtual bool shouldAutoAddContactType(uint8_t type) const { return true; }
   virtual void onContactsFull() {};
   virtual bool shouldOverwriteWhenFull() const { return false; }
+  virtual uint8_t getAutoAddMaxHops() const { return 0; }  // 0 = no limit, 1 = direct (0 hops), N = up to N-1 hops
   virtual void onContactOverwrite(const uint8_t* pub_key) {};
   virtual void onDiscoveredContact(ContactInfo& contact, bool is_new, uint8_t path_len, const uint8_t* path) = 0;
   virtual ContactInfo* processAck(const uint8_t *data) = 0;

src/helpers/ClientACL.cpp

@@ -114,7 +114,7 @@ ClientInfo* ClientACL::putClient(const mesh::Identity& id, uint8_t init_perms) {
   memset(c, 0, sizeof(*c));
   c->permissions = init_perms;
   c->id = id;
-  c->out_path_len = -1;  // initially out_path is unknown
+  c->out_path_len = OUT_PATH_UNKNOWN;
   return c;
 }
 

src/helpers/ClientACL.h

@@ -10,10 +10,12 @@
 #define PERM_ACL_READ_WRITE    2
 #define PERM_ACL_ADMIN         3
 
+#define OUT_PATH_UNKNOWN  0xFF
+
 struct ClientInfo {
   mesh::Identity id;
   uint8_t permissions;
-  int8_t out_path_len;
+  uint8_t out_path_len;
   uint8_t out_path[MAX_PATH_SIZE];
   uint8_t shared_secret[PUB_KEY_SIZE];
   uint32_t last_timestamp;   // by THEIR clock  (transient)

src/helpers/CommonCLI.cpp

@@ -63,7 +63,8 @@ void CommonCLI::loadPrefsInt(FILESYSTEM* fs, const char* filename) {
     file.read((uint8_t *)&_prefs->multi_acks, sizeof(_prefs->multi_acks));                         // 115
     file.read((uint8_t *)&_prefs->bw, sizeof(_prefs->bw));                                         // 116
     file.read((uint8_t *)&_prefs->agc_reset_interval, sizeof(_prefs->agc_reset_interval));         // 120
-    file.read(pad, 3);                                                                             // 121
+    file.read((uint8_t *)&_prefs->path_hash_mode, sizeof(_prefs->path_hash_mode));                 // 121
+    file.read(pad, 2);                                                                             // 122
     file.read((uint8_t *)&_prefs->flood_max, sizeof(_prefs->flood_max));                           // 124
     file.read((uint8_t *)&_prefs->flood_advert_interval, sizeof(_prefs->flood_advert_interval));   // 125
     file.read((uint8_t *)&_prefs->interference_threshold, sizeof(_prefs->interference_threshold)); // 126
@@ -81,7 +82,9 @@ void CommonCLI::loadPrefsInt(FILESYSTEM* fs, const char* filename) {
     file.read((uint8_t *)&_prefs->discovery_mod_timestamp, sizeof(_prefs->discovery_mod_timestamp)); // 162
     file.read((uint8_t *)&_prefs->adc_multiplier, sizeof(_prefs->adc_multiplier)); // 166
     file.read((uint8_t *)_prefs->owner_info, sizeof(_prefs->owner_info));  // 170
-    // 290
+    file.read((uint8_t *)&_prefs->flood_advert_base, sizeof(_prefs->flood_advert_base));                 // 290
+
+    // 294
 
     // sanitise bad pref values
     _prefs->rx_delay_base = constrain(_prefs->rx_delay_base, 0, 20.0f);
@@ -95,6 +98,7 @@ void CommonCLI::loadPrefsInt(FILESYSTEM* fs, const char* filename) {
     _prefs->tx_power_dbm = constrain(_prefs->tx_power_dbm, -9, 30);
     _prefs->multi_acks = constrain(_prefs->multi_acks, 0, 1);
     _prefs->adc_multiplier = constrain(_prefs->adc_multiplier, 0.0f, 10.0f);
+    _prefs->path_hash_mode = constrain(_prefs->path_hash_mode, 0, 2);   // NOTE: mode 3 reserved for future
 
     // sanitise bad bridge pref values
     _prefs->bridge_enabled = constrain(_prefs->bridge_enabled, 0, 1);
@@ -108,6 +112,8 @@ void CommonCLI::loadPrefsInt(FILESYSTEM* fs, const char* filename) {
     _prefs->gps_enabled = constrain(_prefs->gps_enabled, 0, 1);
     _prefs->advert_loc_policy = constrain(_prefs->advert_loc_policy, 0, 2);
 
+    _prefs->flood_advert_base = constrain(_prefs->flood_advert_base, 0, 1);
+
     file.close();
   }
 }
@@ -147,7 +153,8 @@ void CommonCLI::savePrefs(FILESYSTEM* fs) {
     file.write((uint8_t *)&_prefs->multi_acks, sizeof(_prefs->multi_acks));                         // 115
     file.write((uint8_t *)&_prefs->bw, sizeof(_prefs->bw));                                         // 116
     file.write((uint8_t *)&_prefs->agc_reset_interval, sizeof(_prefs->agc_reset_interval));         // 120
-    file.write(pad, 3);                                                                             // 121
+    file.write((uint8_t *)&_prefs->path_hash_mode, sizeof(_prefs->path_hash_mode));                 // 121
+    file.write(pad, 2);                                                                             // 122
     file.write((uint8_t *)&_prefs->flood_max, sizeof(_prefs->flood_max));                           // 124
     file.write((uint8_t *)&_prefs->flood_advert_interval, sizeof(_prefs->flood_advert_interval));   // 125
     file.write((uint8_t *)&_prefs->interference_threshold, sizeof(_prefs->interference_threshold)); // 126
@@ -165,7 +172,9 @@ void CommonCLI::savePrefs(FILESYSTEM* fs) {
     file.write((uint8_t *)&_prefs->discovery_mod_timestamp, sizeof(_prefs->discovery_mod_timestamp)); // 162
     file.write((uint8_t *)&_prefs->adc_multiplier, sizeof(_prefs->adc_multiplier));                 // 166
     file.write((uint8_t *)_prefs->owner_info, sizeof(_prefs->owner_info));  // 170
-    // 290
+    file.write((uint8_t *)&_prefs->flood_advert_base, sizeof(_prefs->flood_advert_base));                 // 290
+
+    // 294
 
     file.close();
   }
@@ -325,6 +334,8 @@ void CommonCLI::handleCommand(uint32_t sender_timestamp, const char* command, ch
           sp++;
         }
         *reply = 0;  // set null terminator
+      } else if (memcmp(config, "path.hash.mode", 14) == 0) {
+        sprintf(reply, "> %d", (uint32_t)_prefs->path_hash_mode);
       } else if (memcmp(config, "tx", 2) == 0 && (config[2] == 0 || config[2] == ' ')) {
         sprintf(reply, "> %d", (int32_t) _prefs->tx_power_dbm);
       } else if (memcmp(config, "freq", 4) == 0) {
@@ -362,6 +373,17 @@ void CommonCLI::handleCommand(uint32_t sender_timestamp, const char* command, ch
       } else if (memcmp(config, "bridge.secret", 13) == 0) {
         sprintf(reply, "> %s", _prefs->bridge_secret);
 #endif
+      } else if (memcmp(config, "bootloader.ver", 14) == 0) {
+      #ifdef NRF52_PLATFORM
+          char ver[32];
+          if (_board->getBootloaderVersion(ver, sizeof(ver))) {
+              sprintf(reply, "> %s", ver);
+          } else {
+              strcpy(reply, "> unknown");
+          }
+      #else
+          strcpy(reply, "ERROR: unsupported");
+      #endif
       } else if (memcmp(config, "adc.multiplier", 14) == 0) {
         float adc_mult = _board->getAdcMultiplier();
         if (adc_mult == 0.0f) {
@@ -369,6 +391,8 @@ void CommonCLI::handleCommand(uint32_t sender_timestamp, const char* command, ch
         } else {
           sprintf(reply, "> %.3f", adc_mult);
         }
+      } else if (memcmp(config, "flood.advert.base", 17) == 0) {
+          sprintf(reply, "> %s", StrHelper::ftoa(_prefs->flood_advert_base));
       // Power management commands
       } else if (memcmp(config, "pwrmgt.support", 14) == 0) {
 #ifdef NRF52_POWER_MANAGEMENT
@@ -545,6 +569,16 @@ void CommonCLI::handleCommand(uint32_t sender_timestamp, const char* command, ch
         *dp = 0;
         savePrefs();
         strcpy(reply, "OK");
+      } else if (memcmp(config, "path.hash.mode ", 15) == 0) {
+        config += 15;
+        uint8_t mode = atoi(config);
+        if (mode < 3) {
+          _prefs->path_hash_mode = mode;
+          savePrefs();
+          strcpy(reply, "OK");
+        } else {
+          strcpy(reply, "Error, must be 0,1, or 2");
+        }
       } else if (memcmp(config, "tx ", 3) == 0) {
         _prefs->tx_power_dbm = atoi(&config[3]);
         savePrefs();
@@ -616,6 +650,15 @@ void CommonCLI::handleCommand(uint32_t sender_timestamp, const char* command, ch
           _prefs->adc_multiplier = 0.0f;
           strcpy(reply, "Error: unsupported by this board");
         };
+      } else if (memcmp(config, "flood.advert.base ", 18) == 0) {
+        float f = atof(&config[18]);
+        if((f > 0) || (f<1)) {
+          _prefs->flood_advert_base = f;
+          savePrefs();
+          strcpy(reply, "OK");
+        } else {
+          strcpy(reply, "Error: base must be between 0 and 1");
+      }        
       } else {
         sprintf(reply, "unknown config: %s", config);
       }
@@ -691,6 +734,9 @@ void CommonCLI::handleCommand(uint32_t sender_timestamp, const char* command, ch
       LocationProvider * l = _sensors->getLocationProvider();
       if (l != NULL) {
         l->syncTime();
+        strcpy(reply, "ok");
+      } else {
+        strcpy(reply, "gps provider not found");
       }
     } else if (memcmp(command, "gps setloc", 10) == 0) {
       _prefs->node_lat = _sensors->node_lat;
@@ -720,7 +766,7 @@ void CommonCLI::handleCommand(uint32_t sender_timestamp, const char* command, ch
         _prefs->advert_loc_policy = ADVERT_LOC_SHARE;
         savePrefs();
         strcpy(reply, "ok");
-      } else if (memcmp(command+11, "prefs", 4) == 0) {
+      } else if (memcmp(command+11, "prefs", 5) == 0) {
         _prefs->advert_loc_policy = ADVERT_LOC_PREFS;
         savePrefs();
         strcpy(reply, "ok");

src/helpers/CommonCLI.h

@@ -36,6 +36,7 @@ struct NodePrefs { // persisted to file
   uint8_t flood_max;
   uint8_t interference_threshold;
   uint8_t agc_reset_interval; // secs / 4
+  float flood_advert_base;
   // Bridge settings
   uint8_t bridge_enabled; // boolean
   uint16_t bridge_delay;  // milliseconds (default 500 ms)
@@ -52,6 +53,7 @@ struct NodePrefs { // persisted to file
   uint32_t discovery_mod_timestamp;
   float adc_multiplier;
   char owner_info[120];
+  uint8_t path_hash_mode;   // which path mode to use when sending
 };
 
 class CommonCLICallbacks {

src/helpers/ContactInfo.h

@@ -3,12 +3,14 @@
 #include <Arduino.h>
 #include <Mesh.h>
 
+#define OUT_PATH_UNKNOWN   0xFF
+
 struct ContactInfo {
   mesh::Identity id;
   char name[32];
   uint8_t type;   // on of ADV_TYPE_*
   uint8_t flags;
-  int8_t out_path_len;
+  uint8_t out_path_len;
   mutable bool shared_secret_valid; // flag to indicate if shared_secret has been calculated
   uint8_t out_path[MAX_PATH_SIZE];
   uint32_t last_advert_timestamp;   // by THEIR clock

src/helpers/NRF52Board.cpp

@@ -297,6 +297,25 @@ float NRF52Board::getMCUTemperature() {
   return temp * 0.25f; // Convert to *C
 }
 
+bool NRF52Board::getBootloaderVersion(char* out, size_t max_len) {
+    static const char BOOTLOADER_MARKER[] = "UF2 Bootloader ";
+    const uint8_t* flash = (const uint8_t*)0x000FB000; // earliest known info.txt location is 0xFB90B, latest is 0xFCC4B
+
+    for (uint32_t i = 0; i < 0x3000 - (sizeof(BOOTLOADER_MARKER) - 1); i++) {
+        if (memcmp(&flash[i], BOOTLOADER_MARKER, sizeof(BOOTLOADER_MARKER) - 1) == 0) {
+            const char* ver = (const char*)&flash[i + sizeof(BOOTLOADER_MARKER) - 1];
+            size_t len = 0;
+            while (len < max_len - 1 && ver[len] != '\0' && ver[len] != ' ' && ver[len] != '\n' && ver[len] != '\r') {
+                out[len] = ver[len];
+                len++;
+            }
+            out[len] = '\0';
+            return len > 0; // bootloader string is non-empty
+        }
+    }
+    return false;
+}
+
 bool NRF52Board::startOTAUpdate(const char *id, char reply[]) {
   // Config the peripheral connection with maximum bandwidth
   // more SRAM required by SoftDevice

src/helpers/NRF52Board.h

@@ -50,6 +50,7 @@ public:
   virtual uint8_t getStartupReason() const override { return startup_reason; }
   virtual float getMCUTemperature() override;
   virtual void reboot() override { NVIC_SystemReset(); }
+  virtual bool getBootloaderVersion(char* version, size_t max_len) override;
   virtual bool startOTAUpdate(const char *id, char reply[]) override;
   virtual void sleep(uint32_t secs) override;
 

src/helpers/RefCountedDigitalPin.h

@@ -20,7 +20,10 @@ public:
       digitalWrite(_pin, _active);
     }
   }
+
   void release() {
+    if (_claims == 0) return; // avoid negative _claims
+
     _claims--;
     if (_claims == 0) {
       digitalWrite(_pin, !_active);

src/helpers/StaticPoolPacketManager.cpp

@@ -11,7 +11,7 @@ PacketQueue::PacketQueue(int max_entries) {
 int PacketQueue::countBefore(uint32_t now) const {
   int n = 0;
   for (int j = 0; j < _num; j++) {
-    if (_schedule_table[j] > now) continue;   // scheduled for future... ignore for now
+    if ((int32_t)(_schedule_table[j] - now) > 0) continue;   // scheduled for future... ignore for now
     n++;
   }
   return n;
@@ -21,7 +21,7 @@ mesh::Packet* PacketQueue::get(uint32_t now) {
   uint8_t min_pri = 0xFF;
   int best_idx = -1;
   for (int j = 0; j < _num; j++) {
-    if (_schedule_table[j] > now) continue;   // scheduled for future... ignore for now
+    if ((int32_t)(_schedule_table[j] - now) > 0) continue;   // scheduled for future... ignore for now
     if (_pri_table[j] < min_pri) {  // select most important priority amongst non-future entries
       min_pri = _pri_table[j];
       best_idx = j;
@@ -55,15 +55,15 @@ mesh::Packet* PacketQueue::removeByIdx(int i) {
   return item;
 }
 
-void PacketQueue::add(mesh::Packet* packet, uint8_t priority, uint32_t scheduled_for) {
+bool PacketQueue::add(mesh::Packet* packet, uint8_t priority, uint32_t scheduled_for) {
   if (_num == _size) {
-    // TODO: log "FATAL: queue is full!"
+    return false;
-    return;
   }
   _table[_num] = packet;
   _pri_table[_num] = priority;
   _schedule_table[_num] = scheduled_for;
   _num++;
+  return true;
 }
 
 StaticPoolPacketManager::StaticPoolPacketManager(int pool_size): unused(pool_size), send_queue(pool_size), rx_queue(pool_size) {
@@ -82,7 +82,10 @@ void StaticPoolPacketManager::free(mesh::Packet* packet) {
 }
 
 void StaticPoolPacketManager::queueOutbound(mesh::Packet* packet, uint8_t priority, uint32_t scheduled_for) {
-  send_queue.add(packet, priority, scheduled_for);
+  if (!send_queue.add(packet, priority, scheduled_for)) {
+    MESH_DEBUG_PRINTLN("queueOutbound: send queue full, dropping packet");
+    free(packet);
+  }
 }
 
 mesh::Packet* StaticPoolPacketManager::getNextOutbound(uint32_t now) {
@@ -106,7 +109,10 @@ mesh::Packet* StaticPoolPacketManager::removeOutboundByIdx(int i) {
 }
 
 void StaticPoolPacketManager::queueInbound(mesh::Packet* packet, uint32_t scheduled_for) {
-  rx_queue.add(packet, 0, scheduled_for);
+  if (!rx_queue.add(packet, 0, scheduled_for)) {
+    MESH_DEBUG_PRINTLN("queueInbound: rx queue full, dropping packet");
+    free(packet);
+  }
 }
 mesh::Packet* StaticPoolPacketManager::getNextInbound(uint32_t now) {
   return rx_queue.get(now);

src/helpers/StaticPoolPacketManager.h

@@ -11,7 +11,7 @@ class PacketQueue {
 public:
   PacketQueue(int max_entries);
   mesh::Packet* get(uint32_t now);
-  void add(mesh::Packet* packet, uint8_t priority, uint32_t scheduled_for);
+  bool add(mesh::Packet* packet, uint8_t priority, uint32_t scheduled_for);
   int count() const { return _num; }
   int countBefore(uint32_t now) const;
   mesh::Packet* itemAt(int i) const { return _table[i]; }

src/helpers/radiolib/CustomLLCC68Wrapper.h

@@ -2,6 +2,7 @@
 
 #include "CustomLLCC68.h"
 #include "RadioLibWrappers.h"
+#include "SX126xReset.h"
 
 class CustomLLCC68Wrapper : public RadioLibWrapper {
 public:
@@ -19,4 +20,6 @@ public:
     int sf = ((CustomLLCC68 *)_radio)->spreadingFactor;
     return packetScoreInt(snr, sf, packet_len);
   }
+
+  void doResetAGC() override { sx126xResetAGC((SX126x *)_radio); }
 };

src/helpers/radiolib/CustomLR1110.h

@@ -20,6 +20,8 @@ class CustomLR1110 : public LR1110 {
       return len;
     }
     
+    float getFreqMHz() const { return freqMHz; }
+
     bool isReceiving() {
       uint16_t irq = getIrqStatus();
       bool detected = ((irq & RADIOLIB_LR11X0_IRQ_SYNC_WORD_HEADER_VALID) || (irq & RADIOLIB_LR11X0_IRQ_PREAMBLE_DETECTED));

src/helpers/radiolib/CustomLR1110Wrapper.h

@@ -2,11 +2,13 @@
 
 #include "CustomLR1110.h"
 #include "RadioLibWrappers.h"
+#include "LR11x0Reset.h"
 
 class CustomLR1110Wrapper : public RadioLibWrapper {
 public:
   CustomLR1110Wrapper(CustomLR1110& radio, mesh::MainBoard& board) : RadioLibWrapper(radio, board) { }
-  bool isReceivingPacket() override { 
+  void doResetAGC() override { lr11x0ResetAGC((LR11x0 *)_radio, ((CustomLR1110 *)_radio)->getFreqMHz()); }
+  bool isReceivingPacket() override {
     return ((CustomLR1110 *)_radio)->isReceiving();
   }
   float getCurrentRSSI() override {

src/helpers/radiolib/CustomSTM32WLxWrapper.h

@@ -2,6 +2,7 @@
 
 #include "CustomSTM32WLx.h"
 #include "RadioLibWrappers.h"
+#include "SX126xReset.h"
 #include <math.h>
 
 class CustomSTM32WLxWrapper : public RadioLibWrapper {
@@ -20,4 +21,6 @@ public:
     int sf = ((CustomSTM32WLx *)_radio)->spreadingFactor;
     return packetScoreInt(snr, sf, packet_len);
   }
+
+  void doResetAGC() override { sx126xResetAGC((SX126x *)_radio); }
 };

src/helpers/radiolib/CustomSX1262Wrapper.h

@@ -2,6 +2,7 @@
 
 #include "CustomSX1262.h"
 #include "RadioLibWrappers.h"
+#include "SX126xReset.h"
 
 class CustomSX1262Wrapper : public RadioLibWrapper {
 public:
@@ -22,4 +23,6 @@ public:
   virtual void powerOff() override {
     ((CustomSX1262 *)_radio)->sleep(false);
   }
+
+  void doResetAGC() override { sx126xResetAGC((SX126x *)_radio); }
 };

src/helpers/radiolib/CustomSX1268Wrapper.h

@@ -2,6 +2,7 @@
 
 #include "CustomSX1268.h"
 #include "RadioLibWrappers.h"
+#include "SX126xReset.h"
 
 class CustomSX1268Wrapper : public RadioLibWrapper {
 public:
@@ -19,4 +20,6 @@ public:
     int sf = ((CustomSX1268 *)_radio)->spreadingFactor;
     return packetScoreInt(snr, sf, packet_len);
   }
+
+  void doResetAGC() override { sx126xResetAGC((SX126x *)_radio); }
 };

src/helpers/radiolib/LR11x0Reset.h

@@ -0,0 +1,21 @@
+#pragma once
+
+#include <RadioLib.h>
+
+// Full receiver reset for LR11x0-family chips (LR1110, LR1120, LR1121).
+// Warm sleep powers down analog, calibrate(0x3F) refreshes all calibration blocks,
+// then re-applies RX settings that calibration may reset.
+inline void lr11x0ResetAGC(LR11x0* radio, float freqMHz) {
+  radio->sleep(true, 0);
+  radio->standby(RADIOLIB_LR11X0_STANDBY_RC, true);
+
+  radio->calibrate(RADIOLIB_LR11X0_CALIBRATE_ALL);
+
+  // calibrate(0x3F) defaults image calibration to 902-928MHz band.
+  // Re-calibrate for the actual operating frequency (band=4MHz matches RadioLib default).
+  radio->calibrateImageRejection(freqMHz - 4.0f, freqMHz + 4.0f);
+
+#ifdef RX_BOOSTED_GAIN
+  radio->setRxBoostedGainMode(RX_BOOSTED_GAIN);
+#endif
+}

src/helpers/radiolib/RadioLibWrappers.cpp

@@ -53,13 +53,24 @@ void RadioLibWrapper::triggerNoiseFloorCalibrate(int threshold) {
   }
 }
 
+void RadioLibWrapper::doResetAGC() {
+  _radio->sleep();  // warm sleep to reset analog frontend
+}
+
 void RadioLibWrapper::resetAGC() {
   // make sure we're not mid-receive of packet!
   if ((state & STATE_INT_READY) != 0 || isReceivingPacket()) return;
 
-  // NOTE: according to higher powers, just issuing RadioLib's startReceive() will reset the AGC.
+  doResetAGC();
-  //      revisit this if a better impl is discovered.
   state = STATE_IDLE;   // trigger a startReceive()
+
+  // Reset noise floor sampling so it reconverges from scratch.
+  // Without this, a stuck _noise_floor of -120 makes the sampling threshold
+  // too low (-106) to accept normal samples (~-105), self-reinforcing the
+  // stuck value even after the receiver has recovered.
+  _noise_floor = 0;
+  _num_floor_samples = 0;
+  _floor_sample_sum = 0;
 }
 
 void RadioLibWrapper::loop() {

src/helpers/radiolib/RadioLibWrappers.h

@@ -16,6 +16,7 @@ protected:
   void startRecv();
   float packetScoreInt(float snr, int sf, int packet_len);
   virtual bool isReceivingPacket() =0;
+  virtual void doResetAGC();
 
 public:
   RadioLibWrapper(PhysicalLayer& radio, mesh::MainBoard& board) : _radio(&radio), _board(&board) { n_recv = n_sent = 0; }

src/helpers/radiolib/SX126xReset.h

@@ -0,0 +1,37 @@
+#pragma once
+
+#include <RadioLib.h>
+
+// Full receiver reset for all SX126x-family chips (SX1262, SX1268, LLCC68, STM32WLx).
+// Warm sleep powers down analog, Calibrate(0x7F) refreshes ADC/PLL/image calibration,
+// then re-applies RX settings that calibration may reset.
+inline void sx126xResetAGC(SX126x* radio) {
+  radio->sleep(true);
+  radio->standby(RADIOLIB_SX126X_STANDBY_RC, true);
+
+  uint8_t calData = RADIOLIB_SX126X_CALIBRATE_ALL;
+  radio->mod->SPIwriteStream(RADIOLIB_SX126X_CMD_CALIBRATE, &calData, 1, true, false);
+  radio->mod->hal->delay(5);
+  uint32_t start = millis();
+  while (radio->mod->hal->digitalRead(radio->mod->getGpio())) {
+    if (millis() - start > 50) break;
+    radio->mod->hal->yield();
+  }
+
+  // Calibrate(0x7F) defaults image calibration to 902-928MHz band.
+  // Re-calibrate for the actual operating frequency.
+  radio->calibrateImage(radio->freqMHz);
+
+#ifdef SX126X_DIO2_AS_RF_SWITCH
+  radio->setDio2AsRfSwitch(SX126X_DIO2_AS_RF_SWITCH);
+#endif
+#ifdef SX126X_RX_BOOSTED_GAIN
+  radio->setRxBoostedGainMode(SX126X_RX_BOOSTED_GAIN);
+#endif
+#ifdef SX126X_REGISTER_PATCH
+  uint8_t r_data = 0;
+  radio->readRegister(0x8B5, &r_data, 1);
+  r_data |= 0x01;
+  radio->writeRegister(0x8B5, &r_data, 1);
+#endif
+}

src/helpers/sensors/EnvironmentSensorManager.cpp

@@ -707,7 +707,9 @@ void EnvironmentSensorManager::loop() {
   static long next_gps_update = 0;
 
   #if ENV_INCLUDE_GPS
-  _location->loop();
+  if (gps_active) {
+    _location->loop();
+  }
   if (millis() > next_gps_update) {
 
     if(gps_active){

src/helpers/sensors/MicroNMEALocationProvider.h

@@ -79,7 +79,10 @@ public :
         if (_pin_en != -1) {
             digitalWrite(_pin_en, !PIN_GPS_EN_ACTIVE);
         }
-        if (_peripher_power) _peripher_power->release();  
+        if (_pin_reset != -1) {
+            digitalWrite(_pin_reset, GPS_RESET_FORCE);
+        }
+        if (_peripher_power) _peripher_power->release();
     }
 
     bool isEnabled() override {

variants/heltec_tracker/platformio.ini

@@ -32,6 +32,11 @@ build_flags =
   -D PIN_TFT_LEDA_CTL=21     ; LEDK (switches on/off via mosfet to create the ground)
   -D PIN_GPS_RX=33
   -D PIN_GPS_TX=34
+  -D PIN_GPS_EN=35              ; N-ch MOSFET Q2 drives P-ch high-side switch → active HIGH (default)
+  -D PIN_GPS_RESET=36
+  -D PIN_GPS_RESET_ACTIVE=LOW
+  -D GPS_BAUD_RATE=115200
+  -D ENV_INCLUDE_GPS=1
   -D SX126X_DIO2_AS_RF_SWITCH=true
   -D SX126X_DIO3_TCXO_VOLTAGE=1.8
   -D SX126X_CURRENT_LIMIT=140
@@ -43,6 +48,31 @@ lib_deps =
   stevemarple/MicroNMEA @ ^2.0.6
   adafruit/Adafruit ST7735 and ST7789 Library @ ^1.11.0
 
+[env:Heltec_Wireless_Tracker_companion_radio_usb]
+extends = Heltec_tracker_base
+build_flags =
+  ${Heltec_tracker_base.build_flags}
+  -I src/helpers/ui
+  -I examples/companion_radio/ui-new
+  -D DISPLAY_ROTATION=1
+  -D DISPLAY_CLASS=ST7735Display
+  -D MAX_CONTACTS=350
+  -D MAX_GROUP_CHANNELS=40
+; -D BLE_PIN_CODE=123456 ; HWT will use display for pin
+; -D OFFLINE_QUEUE_SIZE=256
+;  -D BLE_DEBUG_LOGGING=1
+;  -D MESH_PACKET_LOGGING=1
+;  -D MESH_DEBUG=1
+build_src_filter = ${Heltec_tracker_base.build_src_filter}
+  +<helpers/esp32/*.cpp>
+  +<helpers/ui/MomentaryButton.cpp>
+  +<../examples/companion_radio/*.cpp>
+  +<../examples/companion_radio/ui-new/*.cpp>
+  +<helpers/ui/ST7735Display.cpp>
+lib_deps =
+  ${Heltec_tracker_base.lib_deps}
+  densaugeo/base64 @ ~1.4.0
+
 [env:Heltec_Wireless_Tracker_companion_radio_ble]
 extends = Heltec_tracker_base
 build_flags =

variants/heltec_tracker/target.cpp

@@ -16,7 +16,8 @@ WRAPPER_CLASS radio_driver(radio, board);
 
 ESP32RTCClock fallback_clock;
 AutoDiscoverRTCClock rtc_clock(fallback_clock);
-MicroNMEALocationProvider nmea = MicroNMEALocationProvider(Serial1);
+// GPS_EN (GPIO35) drives N-ch MOSFET → P-ch high-side switch; GPS_RESET (GPIO36) active LOW
+MicroNMEALocationProvider nmea = MicroNMEALocationProvider(Serial1, &rtc_clock, GPS_RESET, GPS_EN, &board.periph_power);
 HWTSensorManager sensors = HWTSensorManager(nmea);
 
 #ifdef DISPLAY_CLASS
@@ -58,18 +59,16 @@ mesh::LocalIdentity radio_new_identity() {
 
 void HWTSensorManager::start_gps() {
   if (!gps_active) {
-    board.periph_power.claim();
+    _location->begin();  // Claims periph_power via RefCountedDigitalPin
-
     gps_active = true;
-    Serial1.println("$CFGSYS,h35155*68");
+    Serial1.println("$CFGSYS,h35155*68");  // Configure GPS for all constellations
   }
 }
 
 void HWTSensorManager::stop_gps() {
   if (gps_active) {
     gps_active = false;
-
+    _location->stop();  // Releases periph_power via RefCountedDigitalPin
-    board.periph_power.release();
   }
 }
 

variants/heltec_tracker/target.h

@@ -28,6 +28,7 @@ public:
   const char* getSettingName(int i) const override;
   const char* getSettingValue(int i) const override;
   bool setSettingValue(const char* name, const char* value) override;
+  LocationProvider* getLocationProvider() override { return _location; }
 };
 
 extern HeltecV3Board board;

variants/heltec_tracker_v2/HeltecTrackerV2Board.cpp

@@ -6,18 +6,26 @@ void HeltecTrackerV2Board::begin() {
     pinMode(PIN_ADC_CTRL, OUTPUT);
     digitalWrite(PIN_ADC_CTRL, LOW); // Initially inactive
 
+    // Set up digital GPIO registers before releasing RTC hold. The hold latches
+    // the pad state including function select, so register writes accumulate
+    // without affecting the pad. On hold release, all changes apply atomically
+    // (IO MUX switches to digital GPIO with output already HIGH — no glitch).
     pinMode(P_LORA_PA_POWER, OUTPUT);
     digitalWrite(P_LORA_PA_POWER,HIGH);
+    rtc_gpio_hold_dis((gpio_num_t)P_LORA_PA_POWER);
 
-    rtc_gpio_hold_dis((gpio_num_t)P_LORA_PA_EN);
     pinMode(P_LORA_PA_EN, OUTPUT);
     digitalWrite(P_LORA_PA_EN,HIGH);
+    rtc_gpio_hold_dis((gpio_num_t)P_LORA_PA_EN);
     pinMode(P_LORA_PA_TX_EN, OUTPUT);
     digitalWrite(P_LORA_PA_TX_EN,LOW);
 
-    periph_power.begin();
-
     esp_reset_reason_t reason = esp_reset_reason();
+    if (reason != ESP_RST_DEEPSLEEP) {
+      delay(1);  // GC1109 startup time after cold power-on
+    }
+
+    periph_power.begin();
     if (reason == ESP_RST_DEEPSLEEP) {
       long wakeup_source = esp_sleep_get_ext1_wakeup_status();
       if (wakeup_source & (1 << P_LORA_DIO_1)) {  // received a LoRa packet (while in deep sleep)
@@ -48,7 +56,9 @@ void HeltecTrackerV2Board::begin() {
 
     rtc_gpio_hold_en((gpio_num_t)P_LORA_NSS);
 
-    rtc_gpio_hold_en((gpio_num_t)P_LORA_PA_EN); //It also needs to be enabled in receive mode
+    // Hold GC1109 FEM pins during sleep to keep LNA active for RX wake
+    rtc_gpio_hold_en((gpio_num_t)P_LORA_PA_POWER);
+    rtc_gpio_hold_en((gpio_num_t)P_LORA_PA_EN);
 
     if (pin_wake_btn < 0) {
       esp_sleep_enable_ext1_wakeup( (1L << P_LORA_DIO_1), ESP_EXT1_WAKEUP_ANY_HIGH);  // wake up on: recv LoRa packet

variants/heltec_tracker_v2/platformio.ini

@@ -17,11 +17,11 @@ build_flags =
   -D P_LORA_SCLK=9
   -D P_LORA_MISO=11
   -D P_LORA_MOSI=10
-  -D P_LORA_PA_POWER=7 ;power en
+  -D P_LORA_PA_POWER=7   ; VFEM_Ctrl - GC1109 LDO power enable
-  -D P_LORA_PA_EN=4
+  -D P_LORA_PA_EN=4      ; CSD - GC1109 chip enable (HIGH=on)
-  -D P_LORA_PA_TX_EN=46  ;enable tx
+  -D P_LORA_PA_TX_EN=46  ; CPS - GC1109 PA mode (HIGH=full PA, LOW=bypass)
-  -D LORA_TX_POWER=10 ;If it is configured as 10 here, the final output will be 22 dbm.
+  -D LORA_TX_POWER=10    ; 10dBm + ~11dB GC1109 gain = ~21dBm output
-  -D MAX_LORA_TX_POWER=22 ;Max SX1262 output
+  -D MAX_LORA_TX_POWER=22 ; Max SX1262 output -> ~28dBm at antenna
   -D SX126X_DIO2_AS_RF_SWITCH=true
   -D SX126X_DIO3_TCXO_VOLTAGE=1.8
   -D SX126X_CURRENT_LIMIT=140

variants/heltec_v4/HeltecV4Board.cpp

@@ -7,19 +7,26 @@ void HeltecV4Board::begin() {
     pinMode(PIN_ADC_CTRL, OUTPUT);
     digitalWrite(PIN_ADC_CTRL, LOW); // Initially inactive
 
+    // Set up digital GPIO registers before releasing RTC hold. The hold latches
+    // the pad state including function select, so register writes accumulate
+    // without affecting the pad. On hold release, all changes apply atomically
+    // (IO MUX switches to digital GPIO with output already HIGH — no glitch).
     pinMode(P_LORA_PA_POWER, OUTPUT);
     digitalWrite(P_LORA_PA_POWER,HIGH);
+    rtc_gpio_hold_dis((gpio_num_t)P_LORA_PA_POWER);
 
-    rtc_gpio_hold_dis((gpio_num_t)P_LORA_PA_EN);
     pinMode(P_LORA_PA_EN, OUTPUT);
     digitalWrite(P_LORA_PA_EN,HIGH);
+    rtc_gpio_hold_dis((gpio_num_t)P_LORA_PA_EN);
     pinMode(P_LORA_PA_TX_EN, OUTPUT);
     digitalWrite(P_LORA_PA_TX_EN,LOW);
 
+    esp_reset_reason_t reason = esp_reset_reason();
+    if (reason != ESP_RST_DEEPSLEEP) {
+      delay(1);  // GC1109 startup time after cold power-on
+    }
 
     periph_power.begin();
-
-    esp_reset_reason_t reason = esp_reset_reason();
     if (reason == ESP_RST_DEEPSLEEP) {
       long wakeup_source = esp_sleep_get_ext1_wakeup_status();
       if (wakeup_source & (1 << P_LORA_DIO_1)) {  // received a LoRa packet (while in deep sleep)
@@ -50,7 +57,9 @@ void HeltecV4Board::begin() {
 
     rtc_gpio_hold_en((gpio_num_t)P_LORA_NSS);
 
-    rtc_gpio_hold_en((gpio_num_t)P_LORA_PA_EN); //It also needs to be enabled in receive mode
+    // Hold GC1109 FEM pins during sleep to keep LNA active for RX wake
+    rtc_gpio_hold_en((gpio_num_t)P_LORA_PA_POWER);
+    rtc_gpio_hold_en((gpio_num_t)P_LORA_PA_EN);
 
     if (pin_wake_btn < 0) {
       esp_sleep_enable_ext1_wakeup( (1L << P_LORA_DIO_1), ESP_EXT1_WAKEUP_ANY_HIGH);  // wake up on: recv LoRa packet

variants/heltec_v4/platformio.ini

@@ -22,7 +22,7 @@ build_flags =
   -D P_LORA_PA_TX_EN=46  ; PA CPS - GC1109 TX PA full(High) / bypass(Low)
   -D PIN_USER_BTN=0
   -D PIN_VEXT_EN=36
-  -D PIN_VEXT_EN_ACTIVE=LOW
+  -D PIN_VEXT_EN_ACTIVE=HIGH
   -D LORA_TX_POWER=10 ;If it is configured as 10 here, the final output will be 22 dbm.
   -D MAX_LORA_TX_POWER=22 ; Max SX1262 output
   -D SX126X_REGISTER_PATCH=1       ; Patch register 0x8B5 for improved RX
@@ -54,8 +54,6 @@ build_flags =
   -D PIN_BOARD_SDA=17
   -D PIN_BOARD_SCL=18
   -D PIN_OLED_RESET=21
-  -D ENV_PIN_SDA=4
-  -D ENV_PIN_SCL=3
 build_src_filter= ${Heltec_lora32_v4.build_src_filter}
 lib_deps = ${Heltec_lora32_v4.lib_deps}
 

variants/heltec_v4/target.cpp

@@ -24,7 +24,7 @@ AutoDiscoverRTCClock rtc_clock(fallback_clock);
 #endif
 
 #ifdef DISPLAY_CLASS
-  DISPLAY_CLASS display(&(board.periph_power));
+  DISPLAY_CLASS display(NULL);
   MomentaryButton user_btn(PIN_USER_BTN, 1000, true);
 #endif
 

variants/lilygo_tbeam_supreme_SX1262/platformio.ini

@@ -26,7 +26,9 @@ build_src_filter = ${esp32_base.build_src_filter}
   +<helpers/ui/SH1106Display.cpp>
   +<helpers/esp32/TBeamBoard.cpp>
   +<helpers/sensors>
-board_build.partitions = min_spiffs.csv ; get around 4mb flash limit
+board_build.partitions = default_8MB.csv
+board_upload.flash_size = 8MB
+board_upload.maximum_size = 8388608
 lib_deps =
   ${esp32_base.lib_deps}
   lewisxhe/XPowersLib @ ^0.2.7
@@ -131,3 +133,27 @@ build_src_filter = ${T_Beam_S3_Supreme_SX1262.build_src_filter}
 lib_deps =
   ${T_Beam_S3_Supreme_SX1262.lib_deps}
   densaugeo/base64 @ ~1.4.0
+
+[env:T_Beam_S3_Supreme_SX1262_companion_radio_wifi]
+extends = T_Beam_S3_Supreme_SX1262
+build_flags =
+  ${T_Beam_S3_Supreme_SX1262.build_flags}
+  -I examples/companion_radio/ui-new
+  -D MAX_CONTACTS=350
+  -D MAX_GROUP_CHANNELS=40
+  -D OFFLINE_QUEUE_SIZE=256
+  -D WIFI_SSID='"WIFI_SSID"'
+  -D WIFI_PWD='"Password"'
+;  -D WIFI_DEBUG_LOGGING=1
+;  -D MESH_PACKET_LOGGING=8
+;  -D MESH_DEBUG=1
+;  -D ARDUHAL_LOG_LEVEL=4
+;  -D CORE_DEBUG_LEVEL=4
+build_src_filter = ${T_Beam_S3_Supreme_SX1262.build_src_filter}
+  +<helpers/esp32/*.cpp>
+  +<helpers/ui/MomentaryButton.cpp>
+  +<../examples/companion_radio/*.cpp>
+  +<../examples/companion_radio/ui-new/*.cpp>
+lib_deps =
+  ${T_Beam_S3_Supreme_SX1262.lib_deps}
+  densaugeo/base64 @ ~1.4.0

variants/m5stack_unit_c6l/platformio.ini

@@ -94,6 +94,8 @@ build_flags = ${M5Stack_Unit_C6L.build_flags}
   -D MAX_CONTACTS=350
   -D MAX_GROUP_CHANNELS=40
   -D OFFLINE_QUEUE_SIZE=256
+  -D ARDUINO_USB_CDC_ON_BOOT=1
+  -D ARDUINO_USB_MODE=1
 build_src_filter = ${M5Stack_Unit_C6L.build_src_filter}
   +<helpers/esp32/*.cpp>
   -<helpers/esp32/ESPNOWRadio.cpp>

variants/rak3401/RAK3401Board.cpp

@@ -20,13 +20,29 @@ void RAK3401Board::begin() {
 
   Wire.begin();
 
+  // PIN_3V3_EN (WB_IO2, P0.34) controls the 3V3_S switched peripheral rail
+  // AND the 5V boost regulator (U5) on the RAK13302 that powers the SKY66122 PA.
+  // Must stay HIGH during radio operation — do not toggle for power saving.
   pinMode(PIN_3V3_EN, OUTPUT);
   digitalWrite(PIN_3V3_EN, HIGH);
 
-#ifdef P_LORA_PA_EN
+  // Enable SKY66122-11 FEM on the RAK13302 module.
-  // Initialize RAK13302 1W LoRa transceiver module PA control pin
+  // CSD and CPS are tied together on the RAK13302 PCB, routed to IO3 (P0.21).
-  pinMode(P_LORA_PA_EN, OUTPUT);
+  // HIGH = FEM active (LNA for RX, PA path available for TX).
-  digitalWrite(P_LORA_PA_EN, LOW);  // Start with PA disabled
+  // TX/RX switching (CTX) is handled by SX1262 DIO2 via SetDIO2AsRfSwitchCtrl.
-  delay(10);  // Allow PA module to initialize
+  pinMode(SX126X_POWER_EN, OUTPUT);
+  digitalWrite(SX126X_POWER_EN, HIGH);
+  delay(1);  // SKY66122 turn-on settling time (tON = 3us typ)
+}
+
+#ifdef NRF52_POWER_MANAGEMENT
+void RAK3401Board::initiateShutdown(uint8_t reason) {
+  // Disable SKY66122 FEM (CSD+CPS LOW = shutdown, <1 uA)
+  digitalWrite(SX126X_POWER_EN, LOW);
+
+  // Disable 3V3 switched peripherals and 5V boost
+  digitalWrite(PIN_3V3_EN, LOW);
+
+  enterSystemOff(reason);
+}
 #endif
-}

variants/rak3401/RAK3401Board.h

@@ -38,13 +38,6 @@ public:
     return "RAK 3401";
   }
 
-#ifdef P_LORA_PA_EN
+  // TX/RX switching is handled by SX1262 DIO2 -> SKY66122 CTX (hardware-timed).
-  void onBeforeTransmit() override {
+  // No onBeforeTransmit/onAfterTransmit overrides needed.
-    digitalWrite(P_LORA_PA_EN, HIGH);  // Enable PA before transmission
-  }
-
-  void onAfterTransmit() override {
-    digitalWrite(P_LORA_PA_EN, LOW);   // Disable PA after transmission to save power
-  }
-#endif
 };

variants/rak3401/platformio.ini

@@ -11,6 +11,7 @@ build_flags = ${nrf52_base.build_flags}
   -D LORA_TX_POWER=22
   -D SX126X_CURRENT_LIMIT=140
   -D SX126X_RX_BOOSTED_GAIN=1
+  -D SX126X_REGISTER_PATCH=1       ; Patch register 0x8B5 for improved RX with SKY66122 FEM
 build_src_filter = ${nrf52_base.build_src_filter}
   +<../variants/rak3401>
   +<helpers/sensors>

variants/rak3401/variant.h

@@ -147,8 +147,15 @@ static const uint8_t AREF = PIN_AREF;
 #define SX126X_BUSY (9)
 #define SX126X_RESET (4)
 
-#define SX126X_POWER_EN (21)
+// SKY66122-11 FEM control on the RAK13302 module:
-// DIO2 controlls an antenna switch and the TCXO voltage is controlled by DIO3
+//   CSD + CPS are tied together on the PCB, routed to WisBlock IO3 (P0.21).
+//   Setting IO3 HIGH enables the FEM (LNA for RX, PA path for TX).
+//   CTX is connected to SX1262 DIO2 — the radio handles TX/RX switching
+//   in hardware via SetDIO2AsRfSwitchCtrl (microsecond-accurate, no GPIO needed).
+//   The 5V boost for the PA is enabled by WB_IO2 (P0.34 = PIN_3V3_EN).
+#define SX126X_POWER_EN (21)        // P0.21 = IO3 -> SKY66122 CSD+CPS (FEM enable)
+
+// CTX is driven by SX1262 DIO2, not a GPIO
 #define SX126X_DIO2_AS_RF_SWITCH
 #define SX126X_DIO3_TCXO_VOLTAGE 1.8
 
@@ -159,7 +166,6 @@ static const uint8_t AREF = PIN_AREF;
 #define P_LORA_DIO_1 SX126X_DIO1
 #define P_LORA_BUSY SX126X_BUSY
 #define P_LORA_RESET SX126X_RESET
-#define P_LORA_PA_EN  31
 
 // enables 3.3V periphery like GPS or IO Module
 // Do not toggle this for GPS power savings

variants/rak4631/variant.h

@@ -106,7 +106,7 @@ extern "C"
 
 // Power management boot protection threshold (millivolts)
 // Set to 0 to disable boot protection
-#define PWRMGT_VOLTAGE_BOOTLOCK 3300   // Won't boot below this voltage (mV)
+#define PWRMGT_VOLTAGE_BOOTLOCK 0   // Won't boot below this voltage (mV)
 // LPCOMP wake configuration (voltage recovery from SYSTEMOFF)
 // AIN3 = P0.05 = PIN_A0 / PIN_VBAT_READ
 #define PWRMGT_LPCOMP_AIN 3