This is the demonstration project for the small but powerful libesphttpd webserver for LinkNode D1. It is an example of how to make a module that can have the AP it connects to configured over a webbrowser. It also illustrates multiple flash layouts and some OTA update functionality.
1. About the webserver
- Supports multiple connections, for eg simultaneous html/css/js/images downloading
- Static files stored in flash, in an (optionally compressed) RO filesystem
- Pluggable using external cgi routines
- Simple template engine for mixed c and html things
- Usable as an embedded library – should be easy to drop into your existing projects
- Includes websocket support
2. Source code
The official esphttpd repo lives at http://git.spritesserver.nl/esphttpd.git/ and http://git.spritesserver.nl/libesphttpd.git/ .
If you’re a fan of Github, you can also peruse the official mirror at https://github.com/Spritetm/esphttpd andhttps://github.com/Spritetm/libesphttpd . If you want to discuss this code, there is a subforum at esp8266.com:http://www.esp8266.com/viewforum.php?f=34 .
3. About the example
When you flash the example into an ESP8266(EX) module, you get a small webserver with a few example pages. If you’ve already connected your module to your WLAN before, it’ll keep those settings. When you haven’t or the settings are wrong, keep GPIO0 for >5 seconds. The module will reboot into its STA+AP mode. Connect a computer to the newly formed access point and browse to http://192.168.4.1/wifi in order to connect the module to your WiFi network. The example also allows you to control a LED that’s connected to GPIO2.
4. Build everything
Required
For this, you need an environment that can compile ESP8266 firmware. Environments for this still are in flux at the moment, but I’m using esp-open-sdk: https://github.com/pfalcon/esp-open-sdk .
You probably also need an UNIX-like system; I’m working on Debian Linux myself.
To manage the paths to all this, you can source a small shell fragment into your current session. For example, I source a file with these contents:
export PATH=${PWD}/esp-open-sdk/xtensa-lx106-elf/bin:$PATH
export SDK_BASE=${PWD}/esp-open-sdk/sdk
export ESPTOOL=${PWD}/esptool/esptool.py
export ESPPORT=/dev/ttyUSB0
export ESPBAUD=460800
Actual setup of the SDK and toolchain is out of the scope of this document, so I hope this helps you enough to set up your own if you haven’t already.
If you have that, you can clone out the source code:
git clone http://git.spritesserver.nl/esphttpd.git/
This project makes use of heatshrink, which is a git submodule.
- To fetch the code:
cd esphttpd git submodule init git submodule update
Configure the flash mode as DIO:
vim Makefile
#0: QIO, 1: QOUT, 2: DIO, 3: DOUT ESP_FLASH_MODE=2
Now, build the code:
make USE_OPENSDK=yes
Note: You can also edit the Makefile to change this more permanently.
- Download the program:
make flash
Pages of webserver
You should have a working webserver now.
If LinkNode D1 have not access WiFi hotpot, it will generated a WiFi hotpot which is called ESP_XXXXXX.
Use your mobile phone or PC to connect this hotpot, then open your browser and enter 192.168.4.1, and you will get the following webpages.
- Main page of this webserver
- Update firmware via WiFi
- STA+AP mode, configure the WiFi.
- Turn on or off Build-in LED on LinkNodeD1
Leave a Reply
You must be logged in to post a comment.