ESPlorer is a tool that uploads your LUA scripts to an ESP module that
has been flashed with LUA. At the
moment you can only use ESP8266 based boards but ESP32 is in progress
(or use a dev build for that). You can also use it for microPython, AT
commands and RN2483.
TIP: You will need java installed on your PC to run this program.
This page shows you how to install the program and connect it to an ESP
module. It then gives you a few
example scripts - including a simple web page server - to show you what you can do with lua.
Note: The advantage of Lua is that it is immediately loaded - you
don't compile for a minute and then wait for an upload for a minute. The
disadvantage is that it is a new language to learn. However this page
shows you some of its usage.
Download the zip file and unzip on your PC then double click on the
ESPlorer.bat file. You may have to wait a short time while some libraries
are downloaded and installed. Then you will see the main ESPlorer
Main Esplorer interface
There are two panels - the left one is for script editing and upload -
the right one is for serial communications with the ESP module.
The first thing you need to do is select the COM port in use by the EPS8266 (top right drop down box).
The baud rate will be:
9600 Baud for older nodeMCU installs
(typically what you get when a module has been bought online).
Note: With a newer flash version of nodeMCU you can take advantage of
new features such as a more Object Oriented methods e.g. timer usage.
After setting the baud rate just hit the 'Open' button to connect to the board. You should see the
Esplorer Startup Screen
Now hit the reset hit the reset button on the board or click the RTS
button (twice to hold it active, then inactive) as this is connected the
reset pin (on nodeMCU boards). You should see:
Esplorer Startup with nodeMCU firmware
If you are using a newer flashed nodeMCU you will see something like this:
Note: Don't worry about the gibberish characters
that preceed each reset - these are just status data at a
different baud rate (74880 Baud).
How to Upload a Simple Lua Program using ESPlorer
The following instructions show you how to add a file to the ESp8266
by enetering text into ESPlorer and uploading it to the file system
inside the ESP8266.
Enter the following text on two lines in the left panel of ESPlorer.
Click the save as button (or use File > Save as) and save as "init.lua"
In the lower part of the screen click "Save to ESP". Now click Run
and you should see the following in the Serial terminal window.
You can also see the same output when the reset button is pressed as the file init.lua is run at start up.
Improve ESPlorer upload reliability
I found that the communication was unreliable (probably too many tabs
open in the browser etc.) so if you find the same click the Settings
tab and uncheck the following check button - so that "Dumb Mode" is
unchecked as below. This slows down communication but checks the data
sent so that it is reliably transmitted.
In another session I did not need to do it so experiment with this.
Some Esplorer and Lua commands
Listing the files loaded with Esplorer
If you click the commands tab and then hit the button labelled 'List files' you'll get a list of files similar to the following.
> _dir=function() local k, ----------------------------
init.lua : 30 bytes
Total file(s) : 1
Total size : 30 bytes
Total : 3441461 bytes
Used : 7781 bytes
Remain: 3433680 bytes
Removing a file from the file system
Now remove the file using a lua command:
Enter the command into the bottom right box, then click 'Send'.
Now you will see it has been removed (Use commands tab, 'list Files' button) ----------------------------
No files found.
Total : 3441461 bytes
Used : 7279 bytes
Remain: 3434182 bytes
How to reset the NodeMCU
You can either reset the nodeMCU using the board reset button or hit
the RTS button in the right hand pane twice. or in the command tab click
I find the RTS button to be the most convenient.
The RTS wire is an RS232 control (meaning Request To Send) and
was originally used to signal to a device that the controller wanted to
send some data. Here it is repurposed as a ESP reset signal.
Bottom Left ESPlorer controls
The four bottom left ESPlorer controls let you:
1. Save to ESP
Upload the currently opened file i.e. the visible one in the text window
This also saves the file to the PC and to the ESP module and then runs it.
2. Send to ESP
Executes the currently opened file.
Upload a bunch of files (useful for large
projects). Select multiple files and they get uploaded one after
NEXT: Now you have installed the ESPlorer software its time to make the nodeMCU do some useful stuff. On this page you will find out how to
start using the Lua scripting language. It starts off with a simple LED
blink, progressing to complex code e.g. how to serve a page from the ESP8266 to your
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