From 0cb2ea05f5228530f688a4635d6dd11f5effa477 Mon Sep 17 00:00:00 2001
From: M256-Automation <76175329+M256-Automation@users.noreply.github.com>
Date: Wed, 24 Jun 2026 15:12:50 +0200
Subject: [PATCH 1/2] Olimex ESP32-POE-ISO support

---
 examples/slaveinfo/slaveinfo.ino | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/examples/slaveinfo/slaveinfo.ino b/examples/slaveinfo/slaveinfo.ino
index eb2166d..f94cb17 100644
--- a/examples/slaveinfo/slaveinfo.ino
+++ b/examples/slaveinfo/slaveinfo.ino
@@ -16,6 +16,18 @@
 
 #include <SOEM.h>
 
+// ESP32 boards with internal EMAC (e.g. Olimex ESP32-POE-ISO) need the ETH
+// stack brought up in setup() before ec_init() can open the HAL. The event
+// flag lets setup() block until the PHY reports link-up without any busy-wait
+// in the SOEM layer itself.
+#if defined(ARDUINO_ESP32_POE_ISO) || defined(ARDUINO_ESP32_POE) || defined(SOEM_INTERNAL_ETH)
+#include <ETH.h>
+static volatile bool eth_ready = false;
+static void onEthEvent(arduino_event_id_t e) {
+    if (e == ARDUINO_EVENT_ETH_CONNECTED) eth_ready = true;
+}
+#endif
+
 char IOmap[4096];
 ec_ODlistt ODlist;
 ec_OElistt OElist;
@@ -657,6 +669,15 @@ void app_loop()
 void setup()
 {
     Serial.begin(115200);
+// On ESP32 boards with internal EMAC the ETH stack must be started here so
+// the PHY is powered and the link is up before the first ec_init() call.
+// ETH_PHY_* constants come from the board's pins_arduino.h (e.g. Olimex
+// ESP32-POE-ISO sets ETH_PHY_POWER=12 and ETH_CLK_MODE=ETH_CLOCK_GPIO17_OUT).
+#if defined(ARDUINO_ESP32_POE_ISO) || defined(ARDUINO_ESP32_POE) || defined(SOEM_INTERNAL_ETH)
+    Network.onEvent(onEthEvent);
+    ETH.begin(ETH_PHY_TYPE, ETH_PHY_ADDR, ETH_PHY_MDC, ETH_PHY_MDIO, ETH_PHY_POWER, ETH_CLK_MODE);
+    while (!eth_ready) delay(10);
+#endif
 }
 
 void loop()

From 9aabf6a7a2541c4467c56ece8cac3a139fef0c59 Mon Sep 17 00:00:00 2001
From: M256-Automation <76175329+M256-Automation@users.noreply.github.com>
Date: Wed, 24 Jun 2026 15:13:34 +0200
Subject: [PATCH 2/2] Olimex ESP32-POE-ISO support

---
 src/SOEM.cpp | 77 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 77 insertions(+)

diff --git a/src/SOEM.cpp b/src/SOEM.cpp
index c46a69a..3e74290 100644
--- a/src/SOEM.cpp
+++ b/src/SOEM.cpp
@@ -352,6 +352,83 @@ void hal_ethernet_recv_rel(void)
 }
 #endif
 
+#elif defined(ARDUINO_ESP32_POE_ISO) || \
+      defined(ARDUINO_ESP32_POE)     || \
+      defined(SOEM_INTERNAL_ETH)
+/**************************************************
+  for ESP32 with internal EMAC (e.g. Olimex ESP32-POE-ISO)
+  ETH must be initialised in setup() before ec_init() is called.
+**************************************************/
+
+#include <ETH.h>
+#include "freertos/FreeRTOS.h"
+#include "freertos/queue.h"
+#include "esp_eth.h"
+
+#define HAL_RX_QSIZE 4
+static esp_eth_handle_t s_eth = NULL;
+static QueueHandle_t    s_rxq = NULL;
+struct HalRxFrame { uint8_t *buf; uint32_t len; };
+static unsigned char s_rx_static[1536];
+
+static esp_err_t s_rx_cb(esp_eth_handle_t, uint8_t *buf, uint32_t len, void*)
+{
+    uint8_t *copy = (uint8_t*)malloc(len);
+    if (copy) {
+        memcpy(copy, buf, len);
+        HalRxFrame f = {copy, len};
+        xQueueSend(s_rxq, &f, 0);
+    }
+    free(buf);
+    return ESP_OK;
+}
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int hal_ethernet_open(void)
+{
+    if (s_eth) return 0;
+    if (!s_rxq) { s_rxq = xQueueCreate(HAL_RX_QSIZE, sizeof(HalRxFrame)); if (!s_rxq) return -1; }
+    s_eth = ETH.handle();
+    if (!s_eth) return -2;
+    if (!ETH.linkUp()) return -3;
+    esp_eth_update_input_path(s_eth, s_rx_cb, NULL);
+    return 0;
+}
+
+void hal_ethernet_close(void)
+{
+    s_eth = NULL;  // allow re-open after ec_close() + ec_init()
+}
+
+int hal_ethernet_send(unsigned char *data, int len)
+{
+    if (!s_eth) return -1;
+    return (esp_eth_transmit(s_eth, data, (size_t)len) == ESP_OK) ? 0 : -1;
+}
+
+int hal_ethernet_recv(unsigned char **data)
+{
+    if (!s_rxq) return 0;
+    HalRxFrame f;
+    if (xQueueReceive(s_rxq, &f, 0) == pdTRUE) {
+        uint32_t len = (f.len < sizeof(s_rx_static)) ? f.len : sizeof(s_rx_static);
+        memcpy(s_rx_static, f.buf, len);
+        free(f.buf);
+        *data = s_rx_static;
+        return (int)len;
+    }
+    return 0;
+}
+
+void hal_ethernet_recv_rel(void) {}
+
+#ifdef __cplusplus
+}
+#endif
+
 #else
 /**************************************************
   for Ethernet Shield (W5500)