I have some experience with Arduino, but not (yet) with other AVRs or Raspberry/Orange.
I want to make a project with some slave devices (mostly Arduino Unos, one Arduino Mega). These all need to communicate with a controller.
This controller has about the following requirements: - It need to respond every 5 ms to some messages from the devices, within the next 5 ms. - It needs about 128 KB RAM space, but more would be more comfortable (although 1 GB is enough). - I need quite some 'programming' space (like FLASH) - The program that needs to run on it will be reasonable complex, so using a nice programming language would be convenient (Python/Java/C++) - SD or other nonvolatile storage is mandatory - nRF24LR01+ 2.4 GHz RF Transceiver - Like upto 8 LEDs for status showing - WIFI would be nice - Using an adapter (12V/2A?) would be good, no intention to run it on batteries
I think I can do it with a Teensy or Due, but those are reasonable expensive. Another option is an STM32 kind of AVR.
However, I an noticed Orange Pi Zero, which are very cheap. But I wonder if I get myself in trouble? I know Linux commands, never installed it on a computer though. Someone made a remark in another related question to go for a stronger AVR, but afaik an Orange should be suited very well for this (seeing the limited electronics involved).