Add RAK4631 / RAK10720 PoE + Ethernet companion support (W5100S/RAK13800) 🤖🤖

examples/companion_radio/main.cpp

@@ -71,7 +71,7 @@ static uint32_t _atoi(const char* sp) {
     ArduinoSerialInterface serial_interface;
   #endif
 #elif defined(NRF52_PLATFORM)
-  #ifdef BLE_PIN_CODE
+  #if defined(BLE_PIN_CODE)
     #include <helpers/nrf52/SerialBLEInterface.h>
     SerialBLEInterface serial_interface;
   #elif defined(ETHERNET_ENABLED)
@@ -162,7 +162,7 @@ void setup() {
     #endif
   );
 
-#ifdef BLE_PIN_CODE
+#if defined(BLE_PIN_CODE)
   serial_interface.begin(BLE_NAME_PREFIX, the_mesh.getNodePrefs()->node_name, the_mesh.getBLEPin());
   the_mesh.startInterface(serial_interface);
 #elif defined(ETHERNET_ENABLED)

examples/simple_repeater/main.cpp

@@ -37,7 +37,14 @@ static unsigned long userBtnDownAt = 0;
 
 void setup() {
   Serial.begin(115200);
+#ifdef WITH_W5100S_POE
+  // PoE cold-start: get to board.begin() (which activates the W5100S load)
+  // ASAP, before the RAK19018/Silvertel converter folds back. Skip the 1 s
+  // serial-settle delay — there is no operator on the serial port on PoE.
+  delay(20);
+#else
   delay(1000);
+#endif
 
   board.begin();
 
@@ -195,6 +202,12 @@ void loop() {
 #ifdef HAS_EXTERNAL_WATCHDOG
   external_watchdog.loop();
 #endif
+
+#ifdef WITH_W5100S_POE
+  // PoE-powered (RAK19018/Silvertel): the device must NEVER sleep. CPU sleep
+  // drops the current draw below the converter's ~125 mA hold threshold,
+  // making it fold back and reset. Skip the powersaving/sleep path entirely.
+#else
   if (the_mesh.getNodePrefs()->powersaving_enabled && !the_mesh.hasPendingWork()) {
 #if defined(NRF52_PLATFORM)
     board.sleep(0); // nrf ignores seconds param, sleeps whenever possible
@@ -204,4 +217,5 @@ void loop() {
     }
 #endif
   }
+#endif // WITH_W5100S_POE
 }

src/helpers/nrf52/EthernetCLI.h

@@ -27,6 +27,26 @@ static SPIClass ETHERNET_SPI_PORT(NRF_SPIM1, PIN_SPI1_MISO, PIN_SPI1_SCK, PIN_SP
 
 #define ETHERNET_RETRY_INTERVAL_MS 30000
 
+#ifdef WITH_W5100S_POE
+  // Give the RAK19018 (Silvertel) PoE converter time to latch on the current
+  // the W5100S is already drawing (board.begin()'s early RST release +
+  // bit-bang soft-reset) before doing the *disruptive* Ethernet-library
+  // bring-up (another PHY soft-reset + blocking DHCP) — doing that
+  // immediately reliably collapsed the marginal PoE supply.
+  #ifndef ETH_POE_DEFER_MS
+    #define ETH_POE_DEFER_MS 6000
+  #endif
+  #ifndef ETH_STATIC_IP
+    #define ETH_STATIC_IP  192,168,1,50
+  #endif
+  #ifndef ETH_GATEWAY
+    #define ETH_GATEWAY    192,168,1,1
+  #endif
+  #ifndef ETH_SUBNET
+    #define ETH_SUBNET     255,255,255,0
+  #endif
+#endif
+
 static EthernetServer ethernet_server(ETHERNET_TCP_PORT);
 static EthernetClient ethernet_client;
 static volatile bool ethernet_running = false;
@@ -35,6 +55,10 @@ static volatile bool ethernet_running = false;
 static void ethernet_task(void* param) {
   (void)param;
 
+#ifdef WITH_W5100S_POE
+  vTaskDelay(pdMS_TO_TICKS(ETH_POE_DEFER_MS));
+#endif
+
   Serial.println("ETH: Initializing hardware");
   // WB_IO2 (power enable) is already driven HIGH by early constructor
   // in RAK4631Board.cpp to support POE boot.
@@ -51,6 +75,22 @@ static void ethernet_task(void* param) {
   Serial.printf("ETH: MAC: %02X:%02X:%02X:%02X:%02X:%02X\n",
       mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
 
+#ifdef WITH_W5100S_POE
+  // Bounded DHCP with a static-IP fallback, so the node stays reachable even
+  // without a DHCP server (no infinite retry — this build has no battery and
+  // must always come up somewhere).
+  Serial.println("ETH: Attempting DHCP...");
+  if (Ethernet.begin(mac, 10000, 2000) == 0) {
+    Serial.println("ETH: DHCP failed -> static IP fallback");
+    IPAddress ip(ETH_STATIC_IP), gw(ETH_GATEWAY), sn(ETH_SUBNET);
+    Ethernet.begin(mac, ip, gw, gw, sn);
+  }
+  IPAddress ip = Ethernet.localIP();
+  Serial.printf("ETH: IP: %u.%u.%u.%u\n", ip[0], ip[1], ip[2], ip[3]);
+  Serial.printf("ETH: Listening on TCP port %d\n", ETHERNET_TCP_PORT);
+  ethernet_server.begin();
+  ethernet_running = true;
+#else
   // Retry loop: keep trying until we get an IP
   while (!ethernet_running) {
     Serial.println("ETH: Attempting DHCP...");
@@ -75,8 +115,9 @@ static void ethernet_task(void* param) {
     ethernet_server.begin();
     ethernet_running = true;
   }
+#endif
 
-  // DHCP succeeded, task is done
+  // DHCP succeeded (or static fallback applied), task is done
   vTaskDelete(NULL);
 }