Division by Zero questions?

[Daryl Clevenger]

As far as I know, some systems have special values for various conditions
that can result from floating point operations.  Those sytems that do not
have these values dump core, but on those that do, they set the value and
continue onward.  On your Zilog model, I suspect that "INF" is infinity and
is the value set when a floating point division by zero is attempted.  I
do not know what "NAN" means.  Also, I'm not sure what happens if you use
an "INF" value in a computation.  Also, I suspect that there are values to
indicate overflow and underflow.  I believe that much of this is specified
in the IEEE floating point standard, but not all hardware uses this
standard.