
MOTOROLA
M68000 8-/16-/32-BIT MICROPROCESSORS USER’S MANUAL
9-5
Table 9-6. Standard Instruction Execution Times
Instruction
ADD/ADDA
Size
op<ea>, An***
8
(1/0)+
6
(1/0)+
—
—
6
(1/0)+
6
(1/0)+
—
—
—
—
—
—
—
—
8
(1/0)+
6
(1/0)+
op<ea>, Dn
4
(1/0)+
6
(1/0)+
4
(1/0)+
6
(1/0)+
4
(1/0)+
6
(1/0)+
122
(1/0)+
108
(1/0)+
4
(1/0)**
6
(1/0)**
42
(1/0)+*
40
(1/0)*
4
(1/0)+
6
(1/0)+
4
(1/0)+
6
(1/0)+
op Dn, <M>
8
(1/1)+
12
(1/2)+
8
(1/1)+
12
(1/2)+
—
—
—
—
8
(1/1)+
12
(1/2)+
—
—
8
(1/1)+
12
(1/2)+
8
(1/1)+
12
(1/2)+
Byte, Word
Long
Byte, Word
Long
Byte, Word
Long
—
—
Byte, Word
Long
—
—
Byte, Word
Long
Byte, Word
Long
AND
CMP/CMPA
DIVS
DIVU
EOR
MULS/MULU
OR
SUB/SUBA
+ Add effective address calculation time.
* Indicates maximum value.
** Only available address mode is data register direct.
*** Word or long word only.
Table 9-7 Standard Instruction Loop Mode Execution Times
Loop Continued
Valid Count cc False
Loop Terminated
Valid Count cc True
Expired Count
Instruction
ADD
Size
Byte,
Word
Long
Byte,
Word
Long
Byte,
Word
Long
Byte,
Word
Long
Byte,
Word
Long
Byte,
Word
Long
op<ea>,
An*
18
(1/0)
op<ea>,
Dn
16
(1/0)
op Dn,
<ea>
16
(1/1)
op<ea>,
An*
24
(3/0)
op<ea>,
Dn
22
(3/0)
op Dn,
<ea>
22
(3/1)
op<ea>,
An*
22
(3/0)
op<ea>,
Dn
20
(3/0)
op Dn,
<ea>
20
(3/1)
22
(2/0)
—
22
(2/0)
16
(1/0)
24
(2/2)
16
(1/1)
28
(4/0)
—
28
(4/0)
22
(3/0)
30
(4/2)
22
(3/1)
26
(4/0)
—
26
(4/0)
20
(3/0)
28
(4/2)
20
(3/1)
AND
—
22
(2/0)
12
(1/0)
24
(2/2)
—
—
28
(4/0)
18
(3/0)
30
(4/2)
—
—
26
(4/0)
16
(4/0)
28
(4/2)
—
CMP
12
(1/0)
18
(3/0)
16
(3/0)
18
(2/0)
—
18
(2/0)
—
—
24
(4/0)
—
24
(4/0)
—
—
20
(4/0)
—
20
(4/0)
—
—
EOR
16
(1/0)
22
(3/1)
20
(3/1)
—
—
—
24
(2/2)
16
(1/0)
—
—
—
30
(4/2)
22
(3/1)
—
—
—
28
(4/2)
20
(3/1)
OR
16
(1/0)
22
(3/0)
20
(3/0)
—
22
(2/0)
16
(1/0)
24
(2/2)
16
(1/1)
—
28
(4/0)
22
(3/0)
30
(4/2)
22
(3/1)
—
26
(4/0)
20
(3/0)
28
(4/2)
20
(3/1)
SUB
18
(1/0)
24
(3/0)
22
(3/0)
22
(2/0)
20
(2/0)
24
(2/2)
28
(4/0)
26
(4/0)
30
(4/2)
26
(4/0)
24
(4/0)
28
(4/2)
*Word or long word only.
<ea> may be (An), (An)+, or –(An) only. Add two clock periods to the table value if <ea> is –(An).