Load Word From Memory With a 5-Bit Unsigned Constant Offset or Register Offset
LDW
3-137
Instruction Set
SPRU733
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.
Execution
if (cond)
mem
→
dst
else nop
Pipeline
Stage
E1
E2
E3
E4
E5
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
Pipeline