HowTo: ESP8266 - flashing .bin files with the "Esptool" under Windows

The actual flashing of firmware files like .bin files (also called "binarys") to the Wemos D1 Mini, the NodeMcu dev board or any other board based on the ESP8266 is done completely in the background in the Arduino IDE.

This is actually the "esptool" offered by Espressif - the manufacturer of the ESP8266. With the right parameters you can easily transfer finished .bin files to the ESP8266.

An easier and a slightly more challenging way is described in this article.

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Safety instructions

I know the following notes are always kind of annoying and seem unnecessary. Unfortunately, many people who knew "better" have lost eyes, fingers or other things due to carelessness or injured themselves. Data loss is almost negligible in comparison, but even these can be really annoying. Therefore, please take five minutes to read the safety instructions. Because even the coolest project is not worth injury or other trouble.
https://www.nerdiy.de/sicherheitshinweise/

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Requirements

Required tool:
-no-

Required material:
-no-

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The esptool

You can always find the current version of the mentioned "esptool" in the GitHub of the manufacturer under:

https://github.com/espressif/esptool

"Problem" with this is that this tool is a Python script/application and thus cannot be run directly/simply on Windows.

Conveniently, however, Python scripts can also be "packaged" into a compact .exe file. This also makes handling under Windows easier.
How to do this is described in the article Python - Translate Esptool.py to Esptool.exe described.
Alternatively, you can also access (somewhat older) prepared releases at

https://github.com/igrr/esptool-ck/releases

fall back.

For the further course of this article you don't have to organize the esptool yourself but you can simply use the esptool.exe file in the following Git.

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Transfer an existing .bin file with the esptool and the ESPEasy Flasher

If you only want to transfer a .bin file to the ESP8266 with the esptool, you normally have to call the esptool from the command line with the appropriate parameters.

This is often difficult especially for not so advanced users and apart from that simply impractical.

This has also been noticed by others and therefore they have worked on how to make the flash process of the ESP8266 as simple as possible.

One of these results can be found in the following Git repository at

https://github.com/BattloXX/ESPEasyFlasher

as always there is also a backup on the nerdiy git:

https://github.com/Nerdiyde/ESPEasyFlasher

In this Git repository there is a FlashESP8266.exe in addition to the mentioned esptool.exe. The latter works like a graphical user interface, which translates the mouse input into prameters and a command line call. What this means is explained in the next paragraph. The easy way starts right here 🙂

Now you just have to click on the "Flash" button and the selected binary will be transferred to your ESP.

One more important note: The list of available COM ports is only updated by restarting the application. So if you have connected your ESP when the program was already started, you have to close it again and open it again.

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Call Esptool via the command line

As mentioned before, you can also use the esptool directly to transfer an existing binary to your ESP.

To do this, use the command line to call the esptool with specified parameters as follows:

esptool.exe -vv -cd nodemcu -cb 921600 -cp COM32 -ca 0x00000 -cf C:ESPEasy.ino.bin

• The number "921600" corresponds to the baud rate with which your ESP is programmed. This can vary from model to model. Typical baudrates are "9600", "115200" or "921600". If one baudrate does not work you can try another one.
• The part "COM32" corresponds to the COM port under which your connected ESP is accessible.
• "0x00000" corresponds to the memory range from which the binary should be written into the ESP memory. Usually you should not change this value.
• Important is now the part "C:ESPEasy.ino.bin" Here must be the path to your binary. If you have copied your binary to your C: drive and named it "ESPEasy.ino.bin", this value can remain as it is.

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Further information:

https://github.com/arendst/Sonoff-Tasmota/wiki/Esptool

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Have fun with the project

I hope everything worked as described for you. If not or you have questions or suggestions please let me know in the comments. I will then add this to the article if necessary.
Ideas for new projects are always welcome. 🙂

PS Many of these projects - especially the hardware projects - cost a lot of time and money. Of course I do this because I enjoy it, but if you think it's cool that I share the information with you, I would be happy about a small donation to the coffee fund. 🙂