[ale] Linux vs XP Embedded

[John Trostel]

I'd have to agree with Bjorn.  If you need real hard deadlines, then use
a real RTOS (real-time OS).  QNX is a very good choice.  It is
self-hosted (no need to cross compile), and would be more familiar to a
linux programmer than VxWorks would be.  VxWorks is the MS of the RTOS
world, so you end up paying quite a bit for their development
environment.  On the other hand, everyone and their brother will have
drivers for VxWorks too.

I wrote the SW for quite an extensive DAQ system using pSOS.  pSOS was a
competitor of VxWorks before being swallowed up by them and digested. I
had looked at a variety of OS's before going with pSOS.  The decision to
go with pSOS was, in the end, pushed by the upper management types.  I
will forever try to avoid such a situation in the future.  pSOS was
probably the worst possible choice (except for a RT enhanced version of
Windows) that could have been made.  We decided that pSOS stood for
'Pretty Shi**y Operating System'.  That said, once completed, the system
(consisting of over 15 interacting CPU's and innumerable DAQ-type cards)
would run unattended, sucking up data and controlling the experiment,
for weeks on end.  Basically until something else failed.
-- 
John Trostel
jtrostel at mindspring.com
Atlanta, GA USA