What can replace a Yun?

Wireless & IoT
1

Hi,

I run an rPi as a “real” webserver, and have a few Yuns communicating with the rPi via Ethernet or WiFi.

The Yuns are my “slim” webservers, the “Yun-side” takes commands from the rPi, via Ethernet or WiFi, and the “Arduino-side” controls stuff. In my case that’s a bunch of other Arduinos via a nRF24L01+ network.

Basically I need a piece of hardware

  • that can run a basic webserver

  • can drive a nRF24L01 module or other modules

I could go the luxury way and connect an Arduino Uno via I2C or so to the most basic rPi and call this a Yun 2.0.

I could also strip my solution down, cut out the middle-man in the form of the nRF24L01 - network, maybe with an ESPx or a Photon.

What I want to avoid is to invest time into another platform that won’t be around in a year or two. I also need a real microcontroller as the end point, making an LED blink just doesn’t cut it for my purposes.

My concern about the ESP (besides stability) is that it can’t replace an Arduino UNO

  • because there aren’t drivers for most components

  • only a few pins

My concerns about the Photon (and here I ask for input from the experts):

  • The Photon seems to only be able to “call home” into the cloud, not communicate with a device with an IP address defined by me, via a standard protocol like http?

  • Does the Photon have drivers for sensors like RHT03?

Last but not least security… I know the cloud is safe and never down, but I don’t want to expose to the internet any piece of hardware that controls anything of value to me. Can the Photon be told NOT to call home?

Thanks for your input!

jafrei

2

I have an RPi Zero. That $5 board + a $7 WiFi USB dongle + a USB power source is a great little node for doing most things. No ADC though.

I also have a Photon board. I don’t care for Lua, and the C/C++ environment is OK but difficult as compared to my like of Python on the RPi for rapid development.

I fiddled with the Espruino Pico board - has 8266 piggback board. This is all about javascript. Works OK but needs more I/O.

And the microPython port for the 8266. Too little I/O so fare. Small memory is big constraint.

So the RPi Zero (more to ship in Feb) is my top choice.

For sensors, I use XBee Series 1 because their stock firmware can do GPIO/DIO in/out, PWM/analog out, ADC in, reporting on GPIO bit state changes or x samples per second, etc. I have one Xbee on the RPi 2 or RPi Zero (same GPIO pinout) and several XBee adjacent to sensors. This way, all code is on the central RPi - no code on the remotes. RPi uses WiFi and SMB to access my LAN and NAS file server. VNC remote desktop so RPi runs headless.

3

good point - I’ll look into the rPi Zero.