Digital Photo Keychain User Manual

INSTRUCTION DESCRIPTIONS

A - 146 INSTRUCTION SET DETAILS MOTOROLA

Assembler Syntax: LSR D (parallel move)

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 ;shift A1 one bit to the right, set up N4

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.

LSR Logical Shift Right LSR

47 24

C (parallel move)

Operation:

Before Execution After Execution

A A

$37:444445:828180

SR SR

$0300

$0301

$37:222222:828180