Packed Decimal Real; Scientiþc Notation - Motorola MVME167 Series Installation Manual

Packed Decimal Real

This format would appear in memory as:
4-bit sign Þeld
16-bit exponent Þeld
68-bit mantissa Þeld
A packed decimal number takes 12 bytes in memory.
Scientific Notation
This format provides a convenient way to enter and display a
floating point decimal number. Internally, the number is assembled
into a packed decimal number and then converted into a number of
the specified data type.
Entering data in this format requires the following fields:
For more information about the MC68040 floating point unit, refer
to the MC68040 Microprocessor User's Manual.
An optional sign bit (+ or -).
One decimal digit followed by a decimal point.
Up to 17 decimal digits (at least one must be entered).
An optional Exponent field that consists of:
An optional underscore.
The Exponent field identifier, letter ÒEÓ.
An optional Exponent sign (+, -).
From 1 to 3 decimal digits.
Floating Point Support
(4 binary digits)
(4 hex digits)
(17 hex digits)
5
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