user manual

INSTRUCTION DESCRIPTIONS
A - 70 INSTRUCTION SET DETAILS MOTOROLA
Operation: Assembler Syntax:
0 ➞D (parallel move) CLR D (parallel move)
Description: Clear the destination accumulator. This is a 56-bit clear instruction.
Example:
:
CLR A #$7F,N ;clear A, set up N0 addr. reg.
:
Explanation of Example: Prior to execution, the 56-bit A accumulator contains the
value $12:345678:9ABCDE. The execution of the CLR A instruction clears the 56-bit A
accumulator to zero.
Condition Codes:
S — Computed according to the definition in A.5 CONDITION CODE COMPUTATION
L — Set if data limiting has occurred during parallel move
E — Always cleared
U — Always set
N — Always cleared
Z— Always set
V — Always cleared
CLR Clear Accumulator CLR
Before Execution After Execution
A
A
$12:345678:9ABCDE $00:000000:000000
MR CCR
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
LF DM T
**
S1 S0 I1 I0 SLEUNZVC