SAT.F

SAT.F

Saturate Fractional Data Register

SAT.F

 

(DALU)

 

 

Operation

 

Assembler Syntax

If Da > $007FFFFFFF then $007FFF0000 → Dn

SAT.F Da,Dn

 

If Da < $FF80000000 then $FF80000000 → Dn

 

 

Else Da & $FFFFFF0000 → Dn

 

 

Description

SAT.F Da,Dn

If the values of the extension bits [39:32] and bit 31 of the source register are all zeros or all ones (no overflow), the source register is transferred to the destination register, and the LP is cleared. If the source register indicates an overflow, the saturated value (positive or negative depending on bit 39) is transferred to the HP of the destination register, sign-extended, and the LP is cleared. The saturated positive value is $007FFF0000; the saturated negative value is $FF80000000. This operation is independent of the SM bit in SR. It is intended for use after an instruction that is not affected by the saturation mode and before a MOVES instruction.

Status and Conditions that Affect Instruction

None.

Status and Conditions Changed by Instruction

Register Address

Bit Name

Description

Ln

L

Clears the Ln bit in the destination register.

EMR[2]

DOVF

Set if saturation occurs.

Example

sat.f d2,d3

Register/Memory Address

L2:D2

L3:D3

EMR

Before

$1:$00 846D 0000

After

$0:$00 7FFF 0000

$0000 0004

A-378

SC140 DSP Core Reference Manual

Page 692
Image 692
Freescale Semiconductor SC140 specifications Sat.F, Sat.f d2,d3, If Da $007FFFFFFF then $007FFF0000 → Dn, SAT.F Da,Dn