Freescale Semiconductor SC140 MOVES.2F Move Two Fractional Words to MOVES.2F, DaDb → EA

Models: SC140

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MOVES.2F

MOVES.2F Move Two Fractional Words to MOVES.2F

 

Memory With Scaling and

 

Saturation (AGU)

Operation

Assembler Syntax

Da:Db → (EA)

MOVES.2F Da:Db,(EA)

Description

The data that is moved from each register to memory is scaled according to the scaling mode. If the Ln bit is set, the moved data is also saturated. The address register values must be long aligned. This instruction is affected by by SM (Saturation Mode bit - SR[2]). When SM is set, scaling is not performed, and the scale bits S[1:10] have no effect.

MOVES.2F Da:Db,(EA)

Moves two signed fractional words from a data register pair to a memory address pointed to by an address register with an optional offset or post-increment.

The first operand (Da) will be moved to the lower memory address (EA). The second operand (Db) will be moved to memory address (EA + 2). In order to keep this behavior in both big endian and little endian modes, the core will interpret the data bus differently in each mode. See Section 2.4.1, “SC140 Endian Support,” on page 2-56, for more detail on bus and memory behavior for each mode.

Status and Conditions that Affect Instruction

Register Address

Bit Name

Description

MCTL[31:0]

AM3–AM0

Address modification bits when updating R0–R7. Otherwise, the

 

 

instruction is not affected by MCTL.

SR[5:4]

S[1:0]

Scaling mode bits choose: no scaling, scale up one bit, or scale down

 

 

one bit.

Ln

L

Limited values are written to the destination if the Ln bit is set.

EMR[16]

BEM

Set if big endian mode, cleared if little endian mode.

Status and Conditions Changed by Instruction

Register Address

Bit Name

Description

SR[6]

S

Scaling bit, set when the absolute value of either or both of the

 

 

words moved (after scaling and limiting) is greater than or equal to

 

 

0.25 and less than 0.75.

Example

moves.2f d0:d1,(r0)

Register/Memory Address

MCTL

BeforeAfter

$0000 0000

SC140 DSP Core Reference Manual

A-297

Page 611
Image 611
Freescale Semiconductor SC140 specifications MOVES.2F Move Two Fractional Words to MOVES.2F, DaDb → EA, MOVES.2F DaDb,EA