Espressif ESP32-S2 Programming Manual page 185

Chapter 2. API Reference
switch (event_id) {
case ETHERNET_EVENT_CONNECTED:
esp_eth_ioctl(eth_handle, ETH_CMD_G_MAC_ADDR, mac_addr);
ESP_LOGI(TAG,
ESP_LOGI(TAG,
addr[4], mac_addr[5]);
→
break;
case ETHERNET_EVENT_DISCONNECTED:
ESP_LOGI(TAG,
break;
case ETHERNET_EVENT_START:
ESP_LOGI(TAG,
break;
case ETHERNET_EVENT_STOP:
ESP_LOGI(TAG,
break;
default:
break;
}
}
esp_event_loop_create_default();
background
→
esp_event_handler_register(ETH_EVENT, ESP_EVENT_ANY_ID, &eth_event_handler,
// register Ethernet event handler (to deal with user specific stuffs when
→
like link up/down happened)
→
Start Ethernet Driver After driver installation, we can start Ethernet immediately.
esp_eth_start(eth_handle);
Connect Driver to TCP/IP Stack
(Open System Interconnection), we're still on level 2 (i.e. Data Link Layer). We can detect link up and down event,
we can gain MAC address in user space, but we can't obtain IP address, let alone send HTTP request. The TCP/IP
stack used in ESP-IDF is called LwIP, for more information about it, please refer to LwIP.
To connect Ethernet driver to TCP/IP stack, these three steps need to follow:
1. Create network interface for Ethernet driver
2. Attach the network interface to Ethernet driver
3. Register IP event handlers
More information about network interface, please refer to
/** Event handler for IP_EVENT_ETH_GOT_IP */
static void got_ip_event_handler(void
{
ip_event_got_ip_t *event
const esp_netif_ip_info_t *ip_info
ESP_LOGI(TAG, "Ethernet Got IP
ESP_LOGI(TAG, "~~~~~~~~~~~");
ESP_LOGI(TAG, "ETHIP:"
ESP_LOGI(TAG, "ETHMASK:"
ESP_LOGI(TAG, "ETHGW:"
ESP_LOGI(TAG, "~~~~~~~~~~~");
}
Espressif Systems
"Ethernet Link Up");
"Ethernet HW Addr
mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_
"Ethernet Link Down");
"Ethernet Started");
"Ethernet Stopped");
// create a default event loop that running
// start Ethernet driver state machine
Up until now, we have installed the Ethernet driver. From the view of OSI
*arg, esp_event_base_t event_base,
int32_t
= (ip_event_got_ip_t *) event_data;
=
Address");
IPSTR, IP2STR(&ip_info->ip));
IPSTR, IP2STR(&ip_info->netmask));
IPSTR, IP2STR(&ip_info->gw));
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%02x:%02x:%02x:%02x:%02x:%02x",
Network Interface.
event_id, void *event_data)
&event->ip_info;
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in␣
NULL);␣
event␣
(continues on next page)
Release v4.4