docs(sntp_example): Add Thread network setup instruction for sntp example

Closes #15605

Author: wqx6

examples/protocols/.build-test-rules.yml

@@ -234,9 +234,12 @@ examples/protocols/smtp_client:
 examples/protocols/sntp:
   <<: *default_rules
   enable:
-    - if: IDF_TARGET == "esp32"
+    - if: IDF_TARGET in ["esp32", "esp32h2"]
       temporary: true
       reason: the other targets are not tested yet
+  disable_test:
+    - if: IDF_TARGET != "esp32"
+      reason: only test on esp32
 
 examples/protocols/sockets:
   <<: *default_rules

examples/protocols/README.md

@@ -4,22 +4,26 @@ Implementation of internet communication protocols and services.
 
 See the [README.md](../README.md) file in the upper level [examples](../) directory for more information about examples.
 
-## Establishing Wi-Fi or Ethernet Connection
+## Establishing Wi-Fi or Ethernet or Thread Connection
 
 ### About the `example_connect()` Function
 
-Protocols examples use a simple helper function, `example_connect()`, to establish Wi-Fi and/or Ethernet connection. This function is implemented in [examples/common_components/protocol_examples_common/include/protocol_examples_common.h](../common_components/protocol_examples_common/include/protocol_examples_common.h), and has a very simple behavior: block until connection is established and IP address is obtained, then return. This function is used to reduce the amount of boilerplate and to keep the example code focused on the protocol or library being demonstrated.
+Protocols examples use a simple helper function, `example_connect()`, to establish Wi-Fi, Ethernet, or/and Thread connection. This function is implemented in [examples/common_components/protocol_examples_common/include/protocol_examples_common.h](../common_components/protocol_examples_common/include/protocol_examples_common.h), and has a very simple behavior: block until connection is established and IP address is obtained, then return. This function is used to reduce the amount of boilerplate and to keep the example code focused on the protocol or library being demonstrated.
 
 The simple `example_connect()` function does not handle timeouts, does not gracefully handle various error conditions, and is only suited for use in examples. When developing real applications, this helper function needs to be replaced with full Wi-Fi / Ethernet connection handling code. Such code can be found in [examples/wifi/getting_started/](../wifi/getting_started) and [examples/ethernet/basic/](../ethernet/basic) examples.
 
 ### Configuring the Example
 
-To configure the example to use Wi-Fi, Ethernet or both connections, open the project configuration menu (`idf.py menuconfig`) and navigate to "Example Connection Configuration" menu. Select either "Wi-Fi" or "Ethernet" or both in the "Connect using" choice.
+To configure the example to use Wi-Fi, Ethernet, Thread or all connections, open the project configuration menu (`idf.py menuconfig`) and navigate to "Example Connection Configuration" menu. Select either "Wi-Fi" or "Ethernet" or "Thread" or all in the "Connect using" choice.
 
 When connecting using Wi-Fi, enter SSID and password of your Wi-Fi access point into the corresponding fields. If connecting to an open Wi-Fi network, keep the password field empty.
 
 When connecting using Ethernet, set up PHY type and configuration in the provided fields. If using Ethernet for the first time, it is recommended to start with the [Ethernet example readme](../ethernet/basic/README.md), which contains instructions for connecting and configuring the PHY. Once Ethernet example obtains IP address successfully, proceed to the protocols example and set the same configuration options.
 
+When connecting using Thread, enter the Thread network parameters in `Component config-->OpenThread-->Thread Core Features-->Thread Operational Dataset`. For instructions on starting or joining a Thread network, refer to the [ot_cli example](../openthread/ot_cli/README.md). If the example requires to access an IPv4 network, a [Thread Border Router](https://openthread.io/guides/border-router) with NAT64 (Network Address Translation IPv6-IPv4) support is needed. You can follow [this guide](https://docs.espressif.com/projects/esp-thread-br/en/latest/codelab/nat64.html) to set up the ESP Thread Border Router for testing.
+
 ### Disabling IPv6
 
-By default, `example_connect()` function waits until Wi-Fi or Ethernet connection is established, and IPv4 address and IPv6 link-local address are obtained. In network environments where IPv6 link-local address cannot be obtained, disable "Obtain IPv6 link-local address" option found in "Example Connection Configuration" menu.
+For examples using Wi-Fi or Ethernet connection, `example_connect()` function waits until Wi-Fi or Ethernet connection is established, and IPv4 address and IPv6 link-local address are obtained. In network environments where IPv6 link-local address cannot be obtained, disable "Obtain IPv6 link-local address" option found in "Example Connection Configuration" menu.
+
+For examples using Thread connection, `example_connect()` waits until Thread device is attached to Thread network, and IPv6 addresses are obtained. Note that IPv6 cannot be disabled for Thread devices as Thread is IPv6-only network.

examples/protocols/sntp/README.md

@@ -1,5 +1,5 @@
-| Supported Targets | ESP32 |
-| ----------------- | ----- |
+| Supported Targets | ESP32 | ESP32-H2 |
+| ----------------- | ----- | -------- |
 
 # Example: using LwIP SNTP module and time functions
 
@@ -9,7 +9,7 @@ This example demonstrates the use of LwIP SNTP module to obtain time from Intern
 
 Open the project configuration menu (`idf.py menuconfig`):
 
-* Configure Wi-Fi or Ethernet under "Example Connection Configuration" menu. See "Establishing Wi-Fi or Ethernet Connection" section in [examples/protocols/README.md](../README.md) for more details.
+* Configure Wi-Fi or Ethernet or Thread under "Example Connection Configuration" menu. See "Establishing Wi-Fi or Ethernet or Thread Connection" section in [examples/protocols/README.md](../README.md) for more details.
 
 * Select one method to synchronize time out of the three available in `CONFIG_SNTP_TIME_SYNC_METHOD` (default `update time immediately when received`).
 
@@ -27,7 +27,7 @@ or to prefer local servers and reduce traffic to the outer world.
 See following menuconfig options:
  * `Component config-->LWIP-->SNTP-->Maximum number of NTP servers`
  * `Component config-->LWIP-->SNTP-->Request NTP servers from DHCP`
- * `Component config-->LWIP-->SNTP-->Maximum number of NTP servers aquired via DHCP`
+ * `Component config-->LWIP-->SNTP-->Maximum number of NTP servers acquired via DHCP`
  * `Component config-->LWIP-->Enable LWIP Debug-->Enable SNTP debug messages`
 
 Please note, that `dhcp_set_ntp_servers()` does not only set NTP servers provided by DHCP, but also resets all other NTP server configured before. If you want to keep both manually configured and DHCP obtained NTP servers, please use the API in this order: