Motorola MVME712AM Installation guide Download

Transcript
Floating Point Support
Packed Decimal Real
This format would appear in memory as:
4-bit sign field
(4 binary digits)
16-bit exponent field
(4 hex digits)
68-bit mantissa field
(17 hex digits)
4
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:
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 "E".
An optional Exponent sign (+, -).
From 1 to 3 decimal digits.
For more information about the MC68040 floating point unit, refer to the
M68040 Microprocessor User’s Manual.
MVME162IG/D2
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