Load Word From Memory With a 5-Bit Unsigned Constant Offset or Register Offset LDW

Execution

Pipeline

Increments and decrements default to 1 and offsets default to 0 when no bracketed register or constant is specified. Loads that do no modification to the baseR can use the syntax *R. Square brackets, [ ], indicate that the ucst5 offset is left-shifted by 2. Parentheses, ( ), can be used to set a nonscaled, constant offset. For example, LDW (.unit) *+baseR (12) dst represents an offset of 12 bytes; whereas, LDW (.unit) *+baseR [12] dst represents an offset of 12 words, or 48 bytes. You must type either brackets or parentheses around the specified offset, if you use the optional offset parameter.

Word addresses must be aligned on word (two LSBs are 0) boundaries.

if (cond)

mem dst

 

 

 

 

else nop

 

 

 

 

 

 

 

 

 

 

 

Pipeline

E1

E2

E3

E4

E5

Stage

 

 

 

 

 

 

Read

baseR

 

 

 

 

 

offsetR

 

 

 

 

Written

baseR

 

 

 

dst

Unit in use

.D

 

 

 

 

 

 

 

 

 

 

Instruction Type

Load

Delay Slots

4 for loaded value

 

0 for address modification from pre/post increment/decrement

 

For more information on delay slots for a load, see Chapter 4.

See Also

LDB, LDDW, LDH

SPRU733

Instruction Set

3-137

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Image 197
Texas Instruments TMS320C67X/C67X+ DSP manual Ldb, Lddw, Ldh, Pipeline Stage Read