lilrags16:
polyglot:
I don't see any actual questions, so I don't know what help you're looking for. You seem to have decided on some hardware, therefore you need to acquire one of each (SD, Ethernet, etc) bit of hardware and write a simple Arduino program to talk to each device. Then integrate them all together with whatever control logic you want.Better yet, think like an engineer and be more formal in your design. Google up "requirements analysis" and "functional/physical allocation", draw out your functional flow diagram, etc. Then you will understand what you are doing and the only remaining questions should be device-specific things.
We can't do your design for you.
I am in an engeneing class. I have diagrams/charts. I'm just making sure I'm noting going to get screwed.
OK so what you have to do is to map out your various input/output requirements and the systems you wish to control. This is a perfect scenario for a state based machine. You are making it way harder and more complex if you bring a 2nd and different Mc into the mix - stick with what people are telling you and get a mega with ethernet.
You want to be careful about using the SD card to control the actions of the mega if you have ethernet access to it then have the Mega act as a basic web client and it can source any updated variables etc from an external web server
What are these "out of this world" relays that need to be controlled - i would be very surprised if there is not a relay shield or an external board that you can source to do the job.
- Map out what needs to be controlled - heater, roof etc
- Map out what needs to be measured - temp, humidity, time etc etc
- Map out what information you wish to make available to the outside world
Have a look at NearBus
A very simple way to have your system send and receive data from the internet and pump it out to google (drive, sheets etc) and respond to inputs from there.
Craig