Lsr - Motorola DSP56000 Manual

LSR

Operation: 0
Assembler Syntax:
Description: Logically shift bits 47–24 of the destination operand D one bit to the right
and store the result in the destination accumulator. Prior to instruction execution, bit 24
of D is shifted into the carry bit C, and a zero is shifted into bit 47 of the destination accu-
mulator D. This instruction is a 24-bit operation. The remaining bits of the destination
operand D are not affected.
Example:
:
LSR A1 A1,N4
:
Before Execution
A
$37:444445:828180
SR
Explanation of Example: Prior to execution, the 56-bit A accumulator contains the
value $37:444445:828180. The execution of the LSR A instruction shifts the 24-bit value
in the A1 register one bit to the right and stores the result back in the A1 register.
A - 146
INSTRUCTION DESCRIPTIONS
Logical Shift Right
47 24
LSR D (parallel move)
;shift A1 one bit to the right, set up N4
$0300
INSTRUCTION SET DETAILS
C (parallel move)
After Execution
A
$37:222222:828180
SR
$0301
LSR
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