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Fmpy//fadd.x floating-point fmpy//fadd.x, Multiply and add – Motorola DSP96002 User Manual

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DSP96002 USER’S MANUAL

MOTOROLA

FMPY//FADD.X

Floating-Point

FMPY//FADD.X

Multiply and Add

Description:

Multiply the two operands S1 and S2, round to single extended precision and store the result in the spec-

ified destination register D1. Simultaneously, add the two operands S3 and D2, round to single extended

precision and store the result in the destination operand D2.

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

Addition Output Operand Precision: SEP Floating-Point.

Multiplication Output Operand Precision: SEP Floating-Point.

CCR Condition Codes:

C

- Not affected.

V

- Not affected.

Z

- Set if result of the addition is zero. Cleared otherwise.

N

- Set if result of the addition is negative. Cleared otherwise.

I

- Set if result of the addition is infinity. Cleared otherwise.

LR

- Not affected.

R

- Not affected.

A

- Not affected.

ER Status Bits:

INX

-Set if the result of the addition or the multiplication is inexact. Cleared otherwise.

DZ

-Always cleared.

UNF

-Set if the result of the addition or the multiplication underflows. Cleared otherwise.

OVF

-Set if the result of the addition or the multiplication overflows. Cleared otherwise.

OPERR-Set if one of the multiply operands is infinity and the other is zero. Set if the addition

operands are opposite-signed infinities. Cleared otherwise.

SNAN -Set if anyone of the source operands is a signaling NaN. Cleared otherwise.

NAN

-Set if result of the addition is a NaN. Cleared otherwise.

UNCC -Always cleared.

Assembler Syntax:

FMPY S1,S2,D1 FADD.X S3,D2

(move syntax - see the MOVE instruction descrip-

tion.)

FMPY S2,S1,D1 FADD.X S3,D2

(move syntax - see the MOVE instruction descrip-

tion.)

Operation:

S1 * S2

ROUND(SEP)

D1

(parallel data bus move)

S3 + D2

ROUND(SEP)

D2