I have a mega ramps 2560, an controller board card ramps 1.4 with drivers for the 3d printer applied to the ramps. I bought a small wifi module: ESP8266. In fact I have no idea how to apply it or run it. I was hoping I could put it in some slots and then just configure it, but I'll have to connect with the welder or maybe bridges ... can anyone help me?
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What are you trying to accomplish?
Have you found any information, instructions, tutorial, etc. about doing this? If so post a link to them, use the chain links icon on the toolbar to make the link clickable.
By default, the ESP8266 communicates over Serial (UART).
There are two main ways to use it: using AT commands (the Mega sends a command for every step the ESP has to take) or by programming the ESP directly (the ESP handles all network related stuff, and only sends relevant information/data to the Arduino).
The advantage of the second method is that you save a lot of resources on the Mega (in terms of RAM and CPU time), the ESP8266 has more RAM than the Mega, and runs at a much faster 160MHz. You can also use the 1-4MB of flash storage of the ESP, and communication is not restricted to Serial only, you can use I²C or SPI as well.
It all depends on your application, of course. What do you want to use it for?
There are countless guides on using AT commands online.
I recommend my Beginner's guide to the ESP8266 for information on the hardware, and how to program it.
Pieter