C251 User's Guide

Double Errors

The 251 does not contain an interrupt vector to trap floating-point errors; therefore, your software must respond appropriately to these error conditions.

In addition to the normal floating-point values, a double number may contain a binary error value. These values are defined as a part of the IEEE standard and are used whenever an error occurs during normal processing of floating-point operations. Your code should check for possible arithmetic errors at the end of each floating-point operation.

The C251 library function _chkdouble_ allows you to quickly check floating-point status on double type numbers.