MC68LC040RC25A Datasheet, PDF (268/442 Pages) Freescale Semiconductor, Inc – M68040 Users Manual

Freescale Semiconductor, Inc.
31 30
23 22
0
DENORMALIZED SINGLE PRECISION S $0
FRACTION
95 94
80 79
64 63 62
40 39
0
FORMAT IN STATE FRAME
$0
$0
0
$0
S EXP
MANTISSA
(a) Single Precision
63 62
52 51
0
DENORMALIZED DOUBLE PRECISION
S $0
MANTISSA
FORMAT IN STATE FRAME
95 94
80 79
64 63 62
$0
$0
0
S EXP
MANTISSA
11 10
0
$0
(b) Double Precision
Figure 9-9. Format of Denormalized Operand in State Frame
9.7 FLOATING-POINT ARITHMETIC EXCEPTIONS
The following eight user floating-point arithmetic exceptions are listed in order of priority.
The MC68040 generates the first seven exceptions in hardware and the eighth only in
software.
• Branch/Set on Unordered (BSUN)
• Signaling Not-A-Number (SNAN)
• Operand Error (OPERR)
• Overflow (OVFL)
• Underflow (UNFL)
• Divide by Zero (DZ)
• Inexact 2 (INEX2)
• Inexact 1 (INEX1)
INEX1 exception is the condition that exists when a packed decimal operand cannot be
converted exactly to the extended-precision format in the current rounding mode. Since
9-24
M68040 USER’S MANUAL
For More Information On This Product,
Go to: www.freescale.com
MOTOROLA