xii
M68040 USER’S MANUAL
MOTOROLA
TABLE OF CONTENTS (Continued)
Paragraph
Number
Page
Number
Title
8.4.6.5
8.4.6.6
8.4.6.7
Write-Back Address and Write-Back Data.....................................
Push Data......................................................................................
Access Error Stack Frame Return From Exception.......................
8-26
8-27
8-27
Section 9
Floating-Point Unit (MC68040 Only)
Floating-Point Unit Pipeline...................................................................
Floating-Point User Programming Model..............................................
Floating-Point Data Registers (FP7–FP0).........................................
Floating-Point Control Register (FPCR) ............................................
Exception Enable Byte...................................................................
Mode Control Byte .........................................................................
Floating-Point Status Register (FPSR)..............................................
Floating-Point Condition Code Byte...............................................
Quotient Byte .................................................................................
Exception Status Byte....................................................................
Accrued Exception (AEXC) Byte. ..................................................
Floating-Point Instruction Address Register (FPIAR) ........................
Floating-Point Data Formats and Data Types.......................................
Computational Accuracy.......................................................................
Intermediate Result ...........................................................................
Rounding the Result..........................................................................
Postprocessing Operation.....................................................................
Underflow, Round, Overflow .............................................................
Conditional Testing............................................................................
Floating-Point Exceptions .....................................................................
Unimplemented Floating-Point Instructions.......................................
Unsupported Floating-Point Data Types ...........................................
Floating-Point Arithmetic Exceptions ....................................................
Branch/Set on Unordered (BSUN) ....................................................
Maskable Exception Conditions.....................................................
Nonmaskable Exception Conditions ..............................................
Signaling Not-a-Number (SNAN).......................................................
Maskable Exception Conditions.....................................................
Nonmaskable Exception Conditions ..............................................
Operand Error ...................................................................................
Maskable Exception Conditions.....................................................
Nonmaskable Exception Conditions ..............................................
Overflow ............................................................................................
Maskable Exception Conditions.....................................................
Nonmaskable Exception Conditions ..............................................
9.1
9.2
9.2.1
9.2.2
9.2.2.1
9.2.2.2
9.2.3
9.2.3.1
9.2.3.2
9.2.3.3
9.2.3.4
9.2.4
9.3
9.4
9.4.1
9.4.2
9.5
9.5.1
9.5.2
9.6
9.6.1
9.6.2
9.7
9.7.1
9.7.1.1
9.7.1.2
9.7.2
9.7.2.1
9.7.2.2
9.7.3
9.7.3.1
9.7.3.2
9.7.4
9.7.4.1
9.7.4.2
9-1
9-2
9-2
9-3
9-3
9-3
9-4
9-4
9-5
9-5
9-5
9-6
9-7
9-11
9-12
9-13
9-15
9-16
9-16
9-20
9-20
9-22
9-24
9-25
9-26
9-27
9-27
9-27
9-27
9-28
9-29
9-30
9-31
9-31
9-31