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Fsub.x floating-point subtract fsub.x – Motorola DSP96002 User Manual

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DSP96002 USER’S MANUAL

MOTOROLA

FSUB.X

Floating-Point Subtract

FSUB.X

Operation:

D - S

ROUND(SEP)

D

(parallel data bus move)

Assembler Syntax:

FSUB.X S,D
(move syntax - see the MOVE instruction description.)

Description:

Subtract the two specified operands, round to single extended precision and store the result in the desti-

nation operand D. For the special case of |S| = |D|, the result can be +0 or -0; the sign of the resulting zero

will be the sign of the input operand in D.

Input Operand(s) Precision: SEP Floating-Point.

Output Operand Precision: SEP Floating-Point.

CCR Condition Codes:

C

- Not affected.

V

- Not affected.

Z

- Set if result is zero. Cleared otherwise.

N

- Set if result is negative. Cleared otherwise.

I

- Set if result is infinity. Cleared otherwise.

LR

- Not affected.

R

- Not affected.

A

- Not affected.

ER Status Bits:

INX

-Set if result is inexact. Cleared otherwise.

DZ

-Always cleared.

UNF

-Set if result underflows. Cleared otherwise.

OVF

-Set if result overflows. Cleared otherwise.

OPERR-Set if operands are like-signed infinities. Cleared otherwise.

SNAN -Set if operand is a signaling NaN. Cleared otherwise.

NAN

-Set if result is a NaN. Cleared otherwise.

UNCC -Always cleared.

IER Flags: Flags changed according to standard definition.