QNX History

I am looking for someone who can chat at the kernel level on older versions
of QNX, particularly the evolution of the microkernel and development of the
interrupt architecture over the entire products’ history. I am doing
research on multithreaded operating systems in the real time space, and am
having a hard time finding anyone who can or will discuss the earliest
versions of QNX and its evolution through the 80s and 90s.

Thanks in advance,