Alsys/HP-RT versus VADSworks/VxWorks

Alsys/HP-RT versus VADSworks/VxWorks

[Paul Lusher]

Greetings...my software engineering group develops real-time, embedded
control systems for the US Navy (shipboard gun fire control systems, 
sensor control systems, etc.).  Most of our 1980's work was in military
computers using CMS2 (Navy high-order language).  Over the last 4-5 yrs.
we've been transitioning to Ada (some C) and other computers (mostly 
VME based processors and the HP-based TAC-3).  For our VME C & Ada work,
we've used VxWorks as the underlying operating system (VxWorks for C,
VADSworks for Ada).  We've found VxWorks to be a very usable OS for our
work (and fairly good basis for Ada runtime) and we've invested a lot
of time in learning to use VxWorks.  On the other hand, VADSworks is
KILLER expensive compared to other options.

Now to my information quest....we're looking at an updated "large" gun 
system (1800 function points) and need to layout a VME architecture
and chose processing cards, Ada compiler, and operating systems!  The 
two main contenders (for various reasons) are:

 1) VADSworks with VxWorks as the underlying operating system;
                probably running on a MVME167 (68040) or one of the
                upcoming, upgraded Motorola Single Board Computers ?

 2) Alsys Ada with HP-RT as the underlying operating system;
                - running on one of the HP boards; likely HP 743i ?

What I really need to know, is how do the two underlying operating 
systems compare for real-time work?  How does HP-RT handle Ada tasks?
How do they compare with on-board debug as far as suspending/resuming 
Ada tasks, looking at variables & memory?  What support does the 
Alsys/HP-RT combo provide for SCSI interfaces, socket communications,
backplane communications, etc.?

Of course, any information on the other parts of this problem (Ada
compiler, VME processors) would be more than appreciated.  Any other
suggested operating systems/Ada compilers?

Thanks for your time; Paul

--------------
Paul W. Lusher                            plusher@relay.nswc.navy.mil
It goes without saying....I don't speak for the Navy, nor the US Govt.