LuaNode

This project is an improved Lua SDK, based on ESP-IDF/ESP8266_RTOS_SDK, for Esp32 (compatible with Esp8266, W800, etc).

ESPRESSIF CHIP FAMILY:

This project is developed by DOIT WiFi team.

DOIT is a high-tech company, focus on IoT. Visit homepage: doit.am

PLATFORM SUPPORTED (NEW):

LuaNode can be running on the following chip/module

• ESP32-WROOM (ESP32C6 including)
• ESP8266
• STM32L4 (Coming soon)

NEW UPDATE FOR ESP32(ESP32C6):

New version of LuaNode32 is developed based on esp-idf and compatible with Esplorer. User can program with Lua, send and save Lua code to hardware via Esplorer.

LuaNode for ESP32C6 is now available! Check this document

How To Build LuaNode32

To build LuaNode firmware for ESP32 series chip, see this Doc

For more details, view LuaNode wiki page

LUA PROGRAMMING:

Examples

---

Programming with Lua is easy, some samples are as follow:

-- create file on file system
file.open("myfile.lua", "w+");
file.write("hello world");
file.close();

-- read file from file system
file.open("myfile.lua", "r");
-- read 1024 bytes from myfile.lua and save them
-- to content
content=file.read(1024);
print(content);
file.close();

-- remove file
file.remove("myfile.lua");

-- restart device
node.restart();

There are some lua sample code within the folder named lua_samples. You can learn how to code with Lua and run the same code on any hardware supported by LuaNode.

You can add your own Lua modules to LuaNode at will, visit the LuaNode wiki page for more details.

Lua Editor

LuaNode is compatible with Esplorer now, you can edit and download Lua Code to hardware via Esplorer conveniently. If you config SPIFFS for your project, you can save your Lua scripts to the file system via ESPlorer.

Get Esplorer Here

HOW TO BUILD For ESP32/ESP8266:

For details, see LuaNode wiki page Here.

HOW TO FLASH THE FIRMWARE:

See LuaNode wiki page Here.

APPS:

• task: This is a sample to show how to create an os task. Build the example by executing the gen_misc.sh.

How to create a task:

void task1(void *pvParameters) {
    // do something
}

void user_init(void) {
    xTaskCreate(task1, (signed char *)"tsk1", 256, &mainqueue, 2, NULL);
}

Note: There is a task to receive uart input. You'd better alloc more than 512k memory for this task, since the lua command handler will be called in this task, more memory is required for lua handler.

• luaapp: A lua app.

• wifikiller: An wifi sample. Set baud rate to 115200pbs, using UART0. It will disconnect WiFi connection.

• wifilister: List all APs, along with clents connected to them, near your device. The list info then sent to Android device via OTG, and display on Android.

APPLICATIONS:

Amazon Alexa for ESP32

This is an awesome application that using Amazon Echo Dot to turn on/off the blue LED on DOIT ESP32 dev-board via voice control service. You can find the source code, named alexa_esp32, within the examples directory. The alexa_esp32 sample can control only one pin, if you want to control more pins or to use more resource on ESP32 to do more things, you can learn the alexa_multi_esp32 sample. The sample will let Alexa to do more things with ESP32.

When you build the alexa_esp32 within the examples folder and flash the firmware to ESP32 board, then you can ask Echo Dot to discover device by telling her "Alexa, discover device". She will answer you "Discovery starting...". After about 20 seconds, if She does find device, she will answer you "I found 1 device...". Plus, you can search device via Alexa App or via this page: alexa.amazon.com. When Echo Dot find ESP32, you will see the found device named "esp" on alexa.amazon.com, show as the following figure:

When Alexa find ESP32 device successfully, you can ask Echo Dot "Alexa, turn on ESP" to turn on the blue LED on ESP32 borad. Ask "Alexa, turn off ESP" to turn off the LED. The following link is a video to show the ESP32 voice control via Amazon Echo Dot: https://youtu.be/Eg1dApUHIBc

ESP32-Camera

This simple application is to use ESP32 to controll a Camera. You can find the source code from the following diretory: LuaNode_Esp32/LuaNode32/examples/camera

There is another ESP32 camera demo create by igrr, find it from the link: https://github.com/igrr/esp32-cam-demo. We also utilize OV7725 for our camera test, but the hardware is a little different from igrr's project. My camera is extended with a RAM, which is AL422B, with 390KB RAM. So the camera can cache 2 frames, if the resolution is set to 320x240 pixel. The following figure is my camera, called "Yehuo", a Chinese name.

The following figures is my ESP32-Camera.

I learn igrr's project, and do the same test as igrr's. For instance, I use the camera to scan the board, and then you can see the output from the uart terminal.

ESP32 Drives Nokia5110 LCD

This is an application to show how to drive Nokia5110 LCD. It is easy for ESP32 to drive the LCD. You don't even need to use SPI to drive the LCD. The LCD is very cheap, and easy to buy from taobao or eBay.

Pin connections:

---

Interface	Nokia5110 Pin	DOIT ESP32 dev-board Pin
RESET	RST	D4
LCD Enable	CE	D2
DC	DC	D5
Data Input	Din	D18
Clock	Clk	D19
Back Light	BL	D21
Power Supply 3.3V	Vcc	3V3
Ground	Gnd	GND

For more details, view the lcd_nokia5110_driver sample within the examples folder.

ESP32 BLE LED controller

This is a sample to show how to create BLE client and BLE server, and create connection between them. To test this sample, you have to prepare two ESP32 dev-board. Then build the sources within the LuaNode_ESP32/examples/ble_led_controller, and flash the client and server firmware to the two ESP32 dev-boards, respectively. you will see the blue LED on the server board is turned on/off each 2 seconds. You can see the test from the following video: https://youtu.be/UnzXCB5EYGU

In this sample, when the client connect to server, it will send BLE notify to the server each 2 seconds. When the server recieves the notification, the server will turn on/off the blue LED on board according to the notification value. If the value is 0x1, the server will turn on the LED, otherwise, the LED will be turned off.

ESP32 communicate with nRF51822 via BLE

This is a example to show how to create BLE connection between ESP32 and nRF51 device (nRF51822 inside). In this sample, ESP32 write "on"/"off" string to the characteristic 6e400002-b5a3-f393-e0a9-e50e24dcca9e, which provided by nRF51 device. When the nRF51 device receives the content sent by ESP32, the nRF51 will turn on/off the LED on board according to the received string. The ESP32 will write "on"/"off" to the characteristic each 2 seconds, so you will see that the LED on nRF51 device blink each 2 seconds.

The folloing video is a test for this example: https://youtu.be/hXuCXh5lEew

The nRF51 device is a nRF51822 dev-board, you can buy it from Taobao China. You can download the sources and build firmware for the nRF51 device from the following link: https://github.com/Nicholas3388/nRF51822_ESP32_communicate

BLE debug tool (LuaNode_BLE_Client)

This is an App (including iOS & Android) for ESP32 as well as other BLE device. The app named LuaNode_BLE_Client. You can use this app to connect to ESP32 and then control the LED on DOIT ESP32 dev board. Plus, you can scan BLE devices around your phone and then view the services, characteristics, and descriptors provided by the devices. Download LuaNode_BLE_Client sources from the following repository: https://github.com/Nicholas3388/LuaNode_BLE_Client

To control the LED on ESP32 board, you have to build the example esp32_ble_gatt_server_led_control_for_phone, and then download the firmware. Run the LuaNode_BLE_Client and then toggle the LED switch on app to turn on/off the LED on board. The following video is a test for ESP32: https://www.youtube.com/watch?v=LhvA33yf7P8

Wifilister

Another interesting application is the Wifilister app. The app scans all APs along with the clients connected to them around device, and scan results are sent to Android device via OTG, then you can see the result displayed on Android device.

To test this app, you have to install the LuanodeUsbHost Android app to your Android phone (device). LuanodeUsbHost is an Android USB Host app for ESP8266/ESP32. The Android device receive messages, sent from ESP8266, via OTG. Then the messages display on this app.

Download the LuanodeUsbHost source Here.

Compile Wifilister provided in Luanode, flash it to ESP8266/ESP32, and then connect your ESP8266/ESP32 with Android phone. You can see the scanning results.

FAQ:

See wiki page Here

WHO ARE THE PEOPLE BEHIND THIS PROJECT

Wei Wang: He got his master's degree from Guilin University of Electronic Technology in 2012. He has more than 4 years work experience on Embedded System.

DOIT(www.doit.am): DOIT is a high-tech company, who focus on IoT technology and open source hardware. He supports this project and provides hardware for this project. Its successful products include WifiMCU, Doit Video Car, and Wifi sniffer, etc.

CONTACT ME:

If you have any question, you can contact me via Email/QQ list below, Thanks:)

• Email: lihonggang@doit.am
• Wechat: andy433928

LOG:

2016.4.7 Modified lbaselib.c

2016.4.19 Modified code structure

2016.5.11 Replace libc

2017.1.19 Update to the latest esp-idf

2018.1.5 Update for the latest esp-idf

2023.12.3 Compatible with latest ESP-IDF(5.x) for ESP32

2023.12.9 Update LuaNode for ESP8266, work with the latest ESP8266_RTOS_SDK, ESP-IDF style.