Keil Logo

float Errors

The C16x/ST10/XC16x does not contain an interrupt vector to trap floating-point errors. Therefore, your software must appropriately respond to these error conditions.

In addition to the normal floating-point values, a float 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.

Name Value Meaning
NaN 0xFFFFFFF Not a number
+INF 0x7F80000 Positive infinity (positive overflow)
-INF 0xFF80000 Negative infinity (negative overflow)


  • The C166 library function _chkfloat_ allows you to quickly check the floating-point status of float numbers.
  Arm logo
Important information

This site uses cookies to store information on your computer. By continuing to use our site, you consent to our cookies.

Change Settings

Privacy Policy Update

Arm’s Privacy Policy has been updated. By continuing to use our site, you consent to Arm’s Privacy Policy. Please review our Privacy Policy to learn more about our collection, use and transfers
of your data.