user manual

INSTRUCTION DESCRIPTIONS
MOTOROLA INSTRUCTION SET DETAILS A - 203
Example:
:
MPYR X1,Y0,A X1,X:(R0)+ Y0,Y:(R4)+N4 ;X1
∗
Y0 ➞ A,save X1 and Y0
:
Explanation of Example: Prior to execution, the 24-bit X1 register contains the value
$123123, the 24-bit Y0 register contains the value $456456, the 16-bit R0 address regis-
ter contains the value $1000, the 16-bit R4 address register contains the value $0100,
the 16-bit N4 address offset register contains the value $0023, the 24-bit X memory loca-
tion X:$1000 contains the value $000000, and the 24-bit Y memory location Y:$0100
contains the value $000000. The execution of the parallel move portion of the instruction,
X1,X:(R0)+ Y0,Y:(R4)+N4, moves the 24-bit value in the X1 register into the 24-bit X
memory location X:$1000 using the 16-bit R0 address register, moves the 24-bit value in
the Y0 register into the 24-bit Y memory location Y:$0100 using the 16-bit R4 address
register, updates the 16-bit value in the R0 address register, and updates the 16-bit R4
address register using the 16-bit N4 address offset register. The contents of the N4
address offset register are not affected.
Condition Codes:
S — Computed according to the definition in A.5 CONDITION CODE COMPUTATION
L — Set if data limiting has occurred during parallel move.
X: Y: XY Memory Data Move X: Y:
Before Execution
After Execution
X1 X1
$123123 $123123
Y0 Y0
$456456 $456456
R0 R0
$1000
$1001
R4 R4
$0100
$0123
X:$1000 X:$1000
$000000
$123123
N4 N4
$0023 $0023
Y:$0100 Y:$0100
$000000
$456456
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 SLEU NZ VC