Freescale Semiconductor SC140 specifications Skipls label

Models: SC140

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SKIPLS

SKIPLS

Skip Loop If LC Less Than or

SKIPLS

 

Equal to Zero (AGU)

 

Operation

Assembler Syntax

 

If LCn ≤ 0,

then PC + displacement → PC SKIPLS label

 

0 → LFn

Description

SKIPLS label

Branches to an address that is the current PC plus the displacement and disables the active loop if its loop counter (LCn) is less than or equal to zero. The displacement is calculated by the assembler and linker. SKIPLS is typically placed before a loop to bypass it if the loop count at run time does not indicate any iterations. Some programming rules apply to the use of this instruction. If no loops are enabled, this instruction is undefined.

Status and Conditions that Affect Instruction

Register Address

Bit Name

Description

SR[30:27]

LF[3:0]

Determines which loop is active.

Status and Conditions Changed by Instruction

Register Address

Bit Name

Description

SR[30:27]

LF[3:0]

Clear the active loop flag if the active loop counter is less than or equal

 

 

to one.

Example

skipls _label

Register/Memory Address

SR

_label (displacement)

PC

Before

$10E0 0000

$0010

$0000 000E

After

$00E0 0000

$0000 001E

A-386

SC140 DSP Core Reference Manual

Page 700
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Freescale Semiconductor SC140 specifications If LCn ≤ Then PC + displacement → PC Skipls label → LFn