RealView® Developer Suite AXD and armsd Debuggers Guide 4.7.7. Floating point

4.7.7. Floating point

Most floating point formats allow you to display or enter very small and very large numerical values without having to use long strings of zeros.

You can enter very precise values by using sufficient significant digits, but the precision that can be stored depends on the number of bits allocated. Generally, if you enter too many significant digits the value is rounded to the nearest value that can be stored.

Four kinds of floating point format are supported:

Floating point

The first character can be a minus sign (-) or a plus sign (+). Remaining characters are decimal digits (0-9) and one decimal point that can be placed at any position among the digits.

A precision of up to about 6 significant figures can be stored. A value stored in this format occupies 32 bits.

Scientific (single precision)

A dialog helps you enter or edit data in this format. You are prompted for the sign and value of the mantissa and the exponent.

A value displayed in this format always has its decimal point after the first significant figure.

This format offers a precision of up to about 6 significant figures. The exponent value must be in the range -38 to +38. This format occupies 32 bits of storage.

Scientific (double precision)

A dialog helps you enter or edit data in this format. You are prompted for the sign and value of the mantissa and the exponent.

A value displayed in this format always has its decimal point after the first significant figure.

This format offers a precision of up to about 15 significant figures. The exponent value must be in the range -308 to +308. This format occupies 64 bits of storage.

Raw floating point

This format enables you to view values in the 80-bit format used in a Floating Point Accelerator (FPA) coprocessor.

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