Having achieved some basic success in getting an ESP8266-01 to connect to IBM IoT and NodeRED I decided (as hinted at at the end of my last blog post) to look at linking it with one of my Arduino Nano's so I could have access to a lot more GPIO's. Oct 7, 2015 - Using any serial comm program you can communicate with the board. This firmware with the modules you need is the online NodeMCU custom builds. The following example uses MQTT to send a signal to the thethings.
![Esp8266 lua examples Esp8266 lua examples](/uploads/1/2/5/6/125616954/905969911.png)
Report the temperature with ESP8266 to MQTT. Soldering iron + wire, Serial USB cable. ' Temperature' statetopic: ' sensor/temperature' qos: 0 unitof. README.md NodeMCU 2.2.0 A Lua based firmware for ESP8266 WiFi SOC NodeMCU is an based firmware for the. The firmware is based on the and uses a file system based on. The code repository consists of 98.1% C-code that glues the thin Lua veneer to the SDK. The NodeMCU firmware is a companion project to the popular, ready-made open source development boards with ESP8266-12E chips.
Summary. Easy to program wireless node and/or access point. Based on Lua 5.1.4 (without debug, os modules). Asynchronous event-driven programming model. more than 65 built-in modules. Firmware available with or without floating point support (integer-only uses less memory). Up-to-date documentation at Programming Model The NodeMCU programming model is similar to that of, only in Lua.
![Software Serial Esp8266 Lua Mqtt Software Serial Esp8266 Lua Mqtt](/uploads/1/2/5/6/125616954/649894387.jpg)
It is asynchronous and event-driven. Liga 37.Germany 38.Germany 39.Germany 40.
35.Germany 36.Germany 3. Prva MF Liga 33. 1 31.France Ligue. Many functions, therefore, have parameters for callback functions. To give you an idea what a NodeMCU program looks like study the short snippets below.
For more extensive examples have a look at the folder in the repository on GitHub. We used a Raspberry Pi to set up an MQTT broker — the central hub of a home data network. Now it’s time to add some sensor and display nodes and get this thing running. So pull out your ESP-8266 module of choice, and let’s get going. For hardware, we’re using a because they’re really cute, and absolutely dirt cheap, but basically any ESP module will do. For instance, you can do the same on the simplest ESP-01 module if you’ve got your own USB-serial adapter and are.
If you insist on a deluxe development board that, we know some people. NodeMCU: Getting the Firmware We’re using the NodeMCU firmware because it’s quick and easy to get running. But you’re not stuck with NodeMCU if you want to go it alone: MQTT has broad support. TuanPM ported over an MQTT library to the and of course there’s, a port for an Arduino-plus-ESP combo. He also ported the MQTT module to NodeMCU that we’ll be using today.
Thanks, TuanPM! Anyway, back to our story. If you haven’t tried out NodeMCU on at least one ESP8266 module, you should give it a try. Here’s the painless way.
Head over to and build yourself a custom firmware with only the modules compiled in that you need. Here, I’ve included dht, file, gpio, mqtt, node, tmr, uart, wifi, and ws2812. (I’ve also included this image as a download in the.) To upload the NodeMCU firmware to the ESP8266, I use, which should work on any platform that Python runs on. Follow the instructions on the esptool GitHub, or just esptool.py -port /dev/ttyUSB0 -baud 57600 writeflash 0x00000 firmware.bin if you’ve done this sort of thing before. (Windows, use COMx for your serial port. Mac people use /dev/cu.usbserial-whatever.) If you have an ESP module without USB-flashing support hardware, you might have to pull GPIO0 to ground on restart — you might have a “flash” button that does this.
Again, the instructions at the esptool GitHub should get you squared away. NodeMCU: Getting Around If you’ve never used NodeMCU before, don’t fret.
It’s a little bit confusing at first because many functions run asynchronously. We’ll handle that when we’re looking at the code. Other than that, Lua is not a difficult language to learn, and you could do worse than to have open in another browser tab. The cool feature of NodeMCU is that it’s run through an interactive serial terminal, so plug up a USB-serial converter if your ESP module doesn’t already have one onboard, connect at 9600 baud, and you’ll be greeted by a friendly prompt. To get the module registered on your local WiFi network, try: wifi.setmode(wifi.STATION) wifi.sta.config('ESSID','password') Wait around ten seconds and you should be set.
Type print(wifi.sta.getip) to confirm that all’s well. We’ll upload a script to automate this before we’re done, but it’s good to see how simple and interactive things can be right from the start. MQTT in NodeMCU So let’s get a little experience with MQTT on the NodeMCU platform. Best keygen software generator. The is pretty good, so open that up to follow along. The centers around the mqtt.Client object and its methods, connect, publish, subscribe, and close. When you create the client, you can also register some callback functions that you’d like to be triggered by certain events, namely connect, offline, and message for when the client connects, goes offline, or receives a message.
If you’ve got your broker set up from last time, let’s send it some messages and monitor them on the broker. Open up a window on the Pi and type mosquittosub -h localhost -v -t home/#.
The node’s MQTT client needs an ID, keepalive time in seconds, username and password, and a clean-session flag. Connecting to the server can be as simple as specifying its IP address, and publishing takes the usual topic, message, QoS, and retain flags. Here’s a minimal demo: m = mqtt.Client('myNodeName', 120, ', ') - blank user and password m:connect('192.168.1.49') - my local broker's IP m:publish('home/test', 'hi from node', 0, 0) - no QoS, not retained Bam!