NodeMCU version unknown

Question

I'm new with NodeMCU firmware use. I have a Amica ESP-12E (v2?) dev kit connected to a DHT22 which I program using the Arduino IDE. All is setup and working fine. My problem came when I wanted to update NodeMCU firmware. Since I don't really know what came pre installed from China, I downloaded ESPlorer to try to determine NodeMCU version. I get the following "error" when I reset the dev board:

Communication with MCU..Got answer! Communication with MCU established. AutoDetect firmware...
Can't autodetect firmware, because proper answer not received (may be unknown firmware). Please, reset module or continue.
{{a long string of weird characters that I can't copy and paste appear here}}

At this point I'm totally clueless about what version of firmware I have. Is there a way to obtain NodeMCU firmware version by software via Arduino IDE code, ESPlorer GUI or something similar?

On the other hand, is there a really easy way to compile/download latest NodeMCU firmware BIN file? Even one with all the modules active will be fine for me now, I'm just trying to understand and test things.

Answer 1

You seem to be confusing two very different platforms. I leave out some details as not to confuse you any further.

• Arduino: you use Arduino programming in the Arduino IDE then build and install a binary to your device whenever the application changes. No NodeMCU firmware needed!
• NodeMCU: you flash the NodeMCU firmware once (e.g. using esptool.py) and then upload Lua code (e.g. using ESPlorer) whenever the application changes. This is more lightweight than the Arduino platform.

On the other hand, is there a really easy way to compile/download latest NodeMCU firmware BIN file?

Yes, have a look at the NodeMCU documentation at http://nodemcu.readthedocs.io/en/latest/en/build/. The easiest is to use the cloud builder at https://nodemcu-build.com/. I currently suggest to build from the dev branch because flashing is easier with it.

Answer 2

As pointed out you have several options for firmware and you'll need to make a choice as to which suits you going forward. If you are going to stick with the Nodemcu LUA firmware you can determine the version by typing:

    print(node.info())

at the command line prompt.

There are alternatives to using ESPlorer e.g. Putty or Coolterm that will give you the raw output from the device with no interpretation. So if you have the correct serial port settings and the device plugged into the USB port it will show the banner when you reset giving an indication of the origin and version of the installed firmware.

Answer 3

In ESPlorer, there is an option under settings which if unchecked will stop looking checking for the version of the code. For whatever reason, ESPlorer is not designed to read nodemcu version.

The error message throws you off, could lead you to think, there is an error.

At best, the above error can be ignored. It has no impact at all. In background, init.lua is up and running.