/diy/ - Do It Yourself

>what's your alternative then
For the arduino guy >>1911077, reading the datasheet and moving into avr-libc rather than shitty arduino sdk and ide. You can use timer interrupts, or implement your own, smarter delay function.
Do Note some atmega chips are supported in nuttx, if they want to play with it.
>>1911411
For you, evaluating other RTOSs (including the nuttx I suggested), and not being such a bore to settle with what the vendor gave you, which is typically a poorly put together freertos port only good enough to get you started. This might involve writing some platform code yourself, to support your hardware. You should not be scared of this.
Freertos is the most pain in the ass among those I tried, so I believe your effort would be rewarded.