Square Root - Motorola DSP96002 User Manual

FSEEDR
Operation:
Approximation(1/SQRT(S))
Description:
Take the contents of the specified source operand S, determine an approximation to sqrt(1.0/S), and store
the result in the destination operand D. The 9 MSBs of the destination significand are determined by using
a lookup ROM. The remaining bits of the significand are zeroed. This instruction is useful for initializing
floating-point square root algorithms.
The table below describes the operation of the FSEEDR instruction:
Source Operand
SNaN or QNaN
less than zero
+/- zero
+ denormalized
+ normalized
+ infinity
Input Operand(s) Precision: SEP Floating-Point.
Output Operand Precision: SEP Floating-Point.
CCR Condition Codes:
C
V
Z
N
I
LR
–
R
A
A - 166

Square Root

Reciprocal Approximation
D
Result
QNaN
QNaN
+/- zero
normalized, then FSEEDR approximation
FSEEDR approximation
+ infinity
- Not affected.
- Not affected.
- Set if result is zero. Cleared otherwise.
- Set if result is negative. Cleared otherwise.
- Set if result is infinity. Cleared otherwise.
- Not affected.
- Not affected.
- Not affected.
DSP96002 USER'S MANUAL
Assembler Syntax:
FSEEDR S,D
FSEEDR
MOTOROLA