mirror of
https://github.com/espressif/esp-idf.git
synced 2025-10-30 12:50:41 +00:00
cc1526c570
- Disable Kconfig option for Wifi if not supported by the SoC - Enable building mqtt examples when target is set to esp32h2
97 lines
3.6 KiB
Markdown
97 lines
3.6 KiB
Markdown
| Supported Targets | ESP32 | ESP32-C2 | ESP32-C3 | ESP32-C6 | ESP32-H2 | ESP32-S2 | ESP32-S3 |
|
|
| ----------------- | ----- | -------- | -------- | -------- | -------- | -------- | -------- |
|
|
|
|
|
|
# CoAP server example
|
|
|
|
(See the README.md file in the upper level 'examples' directory for more information about examples.)
|
|
This CoAP server example is very simplified adaptation of one of the
|
|
[libcoap](https://github.com/obgm/libcoap) examples.
|
|
|
|
CoAP server example will startup a daemon task, receive requests / data from CoAP client and transmit
|
|
data to CoAP client.
|
|
|
|
If the incoming request requests the use of DTLS (connecting to port 5684), then the CoAP server will
|
|
try to establish a DTLS session using the previously defined Pre-Shared Key (PSK) - which
|
|
must be the same as the one that the CoAP client is using, or Public Key Infrastructure (PKI) where
|
|
the PKI information must match as requested.
|
|
|
|
The Constrained Application Protocol (CoAP) is a specialized web transfer protocol for use with
|
|
constrained nodes and constrained networks in the Internet of Things.
|
|
The protocol is designed for machine-to-machine (M2M) applications such as smart energy and
|
|
building automation.
|
|
|
|
Please refer to [RFC7252](https://www.rfc-editor.org/rfc/pdfrfc/rfc7252.txt.pdf) for more details.
|
|
|
|
## How to use example
|
|
|
|
### Configure the project
|
|
|
|
```
|
|
idf.py menuconfig
|
|
```
|
|
|
|
Example Connection Configuration --->
|
|
* Set WiFi SSID
|
|
* Set WiFi Password
|
|
Component config --->
|
|
CoAP Configuration --->
|
|
* Set encryption method definition, PSK (default) or PKI
|
|
* Enable CoAP debugging if required
|
|
* Disable CoAP using TCP if this is not required (TCP needed for TLS)
|
|
* Disable CoAP client functionality to reduce code size unless this server is a proxy
|
|
Example CoAP Server Configuration --->
|
|
* If PSK, Set CoAP Preshared Key to use for connections to the server
|
|
|
|
### Build and Flash
|
|
|
|
Build the project and flash it to the board, then run monitor tool to view serial output:
|
|
|
|
```
|
|
idf.py build
|
|
idf.py -p PORT flash monitor
|
|
```
|
|
|
|
(To exit the serial monitor, type ``Ctrl-]``.)
|
|
|
|
See the Getting Started Guide for full steps to configure and use ESP-IDF to build projects.
|
|
|
|
## Example Output
|
|
current CoAP server would startup a daemon task,
|
|
and the log is such as the following:
|
|
|
|
```
|
|
...
|
|
I (332) wifi: mode : sta (30:ae:a4:04:1b:7c)
|
|
I (1672) wifi: n:11 0, o:1 0, ap:255 255, sta:11 0, prof:1
|
|
I (1672) wifi: state: init -> auth (b0)
|
|
I (1682) wifi: state: auth -> assoc (0)
|
|
I (1692) wifi: state: assoc -> run (10)
|
|
I (1692) wifi: connected with huawei_cw, channel 11
|
|
I (1692) wifi: pm start, type: 1
|
|
|
|
I (2622) event: sta ip: 192.168.3.84, mask: 255.255.255.0, gw: 192.168.3.1
|
|
I (2622) CoAP_server: Connected to AP
|
|
...
|
|
```
|
|
|
|
If a CoAP client queries the `/Espressif` resource, CoAP server will return `"Hello World!"`
|
|
until a CoAP client does a PUT with different data.
|
|
|
|
## libcoap Documentation
|
|
This can be found at [libcoap Documentation](https://libcoap.net/documentation.html).
|
|
The current API is 4.3.0.
|
|
|
|
## libcoap Specific Issues
|
|
These can be raised at [libcoap Issues](https://github.com/obgm/libcoap/issues).
|
|
|
|
## Troubleshooting
|
|
* Please make sure CoAP client fetchs or puts data under path: `/Espressif` or
|
|
fetches `/.well-known/core`
|
|
|
|
* CoAP logging can be enabled by running 'idf.py menuconfig -> Component config -> CoAP Configuration -> Enable CoAP debugging'
|
|
and setting appropriate log level. If Mbed TLS logging is required, this needs to be configured separately under mbedTLS
|
|
Component Configuration and the CoAP logging level set to mbedTLS.
|
|
|
|
* CoAP library does not support IPv6 only configuration, so it is necessary to enable `LWIP_IPv4`
|