I'm looking for a relatively low-cost (<$50 would be ideal) development board with real support for an RTOS. It doesn't matter if the RTOS is manufacturer-supported or a separate project, but I'd like something that is solidly supported (i.e. actually works for multiple people). I've spent some time fixing broken RTOS ports and I'd rather not have to mess with that.
My other requirement is that the development board has to have support for a Linux development environment.
We're looking for something that is specs-wise roughly comparable to the Atmega 2560. (And, in fact, an Arduino Mega 2560 running BeRTOS is certainly one option.)
To give a little more background to the question, last year we built a quadcopter from scratch (i.e. all the hardware, all the code, etc. Nothing borrowed from Arducopter or anything like that). A small budget ($400) had us stuck with an Arduino Pro (an Atmega 328-based board). By the time we had the thing flying, we were bumping up against the memory limit (due to code size) and doing everything we could to optimize so that our PID loops would run fast enough.
The new goal is to redo the control system based on a less limiting micro and an RTOS.
So, to summarize, the question is, what development boards fit these criteria:
- Approx <$50
- RTOS support
- Compatible with a Linux development environment