A basic 900mhz network (client/server)

Hardware: Adafruit Feather 32u4 Radio (RFM69HCW), Raspberry Pi 3 Model B

I've been building a wireless/wired sensor setup which I thought I should document as a pretty handy basic design for almost any basic wireless project.

Essentially this is taking some of the Adafruit Feather 32u4 900mhz (915/868mhz actually) boards and associated radios to connect to various sensors, buttons, etc. and bring all of that back home to a server that eventually processes everything.  I could have done a very similar design with one of the Moteino boards.

Battery voltage check function on Arduino Feather 32u4

Hardware: Adafruit Feather 32u4 Radio (RFM69HCW)

The folks over at Adafruit have done a nice job with some aspects of documentation on these boards.  This is one of those items that they've documented well, but I find just annoying that they don't drop it in as a simple "best practice" kind of thing.

So here it is!

This is a function you can drop into your code anywhere and get results on the battery voltage on any of the Feather 32u4 devices.

Connecting two Pis (or other boxes) directly via TCP/IP without a webserver

Hardware:  Two Raspberry Pi 3 Model B's

Software: 2017-01-11 Raspbian Jessie Lite (minimal) / Python

Sometimes you just need something simple.  

In fact, sometimes the layers of possibilities included with webservers and other high-level communications methods are not exactly a benefit.  In particular, when you're dealing with very basic inter-system communications that are more about keep-alive and simple status messages, larger libraries/methods sometimes come with more burdens than benefits.  This is where socket connections can be applied.