Circuit Board Reference Manual

Floating-Point Exceptions

MCF548x Reference Manual, Rev. 3

Freescale Semiconductor 6-17

6.6 Floating-Point Exceptions

This section describes floating-point exceptions and how they are handled. Table 6-10 lists the vector

numbers related to floating-point exceptions. If the exception is taken pre-instruction, the PC contains the

address of the next floating-point instruction (nextFP). If the exception is taken post-instruction, the PC

contains the address of the faulting instruction (fault).

NGLE Not greater, less or equal NAN 011000 Yes

IEEE-Aware Tests

EQ Equal Z 000001 No

NE Not equal Z

001110 No

OGT Ordered greater than NAN | Z | N 000010 No

ULE Unordered or less or equal NAN | Z | N 001101 No

OGE Ordered greater than or equal Z | (NAN | N) 000011 No

ULT Unordered or less than NAN | (N & Z) 001100 No

OLT Ordered less than N & (NAN | Z) 000100 No

UGE Unordered or greater or equal NAN | (Z | N) 001011 No

OLE Ordered less than or equal Z | (N & NAN) 000101 No

UGT Unordered or greater than NAN | (N | Z) 001010 No

OGL Ordered greater or less than NAN | Z 000110 No

UEQ Unordered or equal NAN | Z 001001 No

OR Ordered NAN 000111 No

UN Unordered NAN 001000 No

Miscellaneous Tests

F False False 000000 No

T True True 001111 No

SF Signaling false False 010000 Yes

ST Signaling true True 011111 Yes

SEQ Signaling equal Z 010001 Yes

SNE Signaling not equal Z

011110 Yes

This column refers to the value in the instruction’s conditional predicate field that specifies this test.

Table 6-9. Floating-Point Conditional Tests (Continued)

Mnemonic Definition Equation Predicate

EXC[BSUN] Set