
4.2 Instruction Set
246
Chapter 4: Instructions
Table 4.2.12 Unsigned Multiplication and Division Instructions (Word/Long-Word) (11 Instructions)
*1:
3 when dividing into zero, 7 when an overflow occurs, and 15 normally.
*2:
4 when dividing into zero, 8 when an overflow occurs, and 16 normally.
*3:
6 + (a) when dividing into zero, 9 + (a) when an overflow occurs, and 19 + (a) normally.
*4:
4 when dividing into zero, 7 when an overflow occurs, and 22 normally.
*5:
6 + (a) when dividing into zero, 8 + (a) when an overflow occurs, and 26 + (a) normally.
*6:
(b) when dividing into zero or when an overflow occurs, and 2 x (b) normally.
*7:
(c) when dividing into zero or when an overflow occurs, and 2 x (c) normally.
*8:
3 when byte (AH) is zero, and 7 when byte (AH) is not 0.
*9:
4 when byte (ear) is zero, and 8 when byte (ear) is not 0.
*10:
5 + (a) when byte (eam) is zero, and 9 + (a) when byte (eam) is not 0.
*11:
3 when word (AH) is zero, and 11 when word (AH) is not 0.
*12:
4 when word (ear) is zero, and 12 when word (ear) is not 0.
*13:
5 + (a) when word (eam) is zero, and 13 + (a) when word (eam) is not 0.
Note:
For an explanation of “(a)” to “(d)”, see Table 4.2.3 and Table 4.2.4.
Mnemonic
#
~
RG
B
Operation
LH
AH
I
S
T
N
Z
V
C
RMW
DIVU
A
DIVU
A,ear
DIVU
A,eam
DIVUW
A,ear
DIVUW
A,eam
MULU
A
MULU
A,ear
MULU
A,eam
MULUW A
MULUW A,ear
MULUW A,eam
1
2
2+
2
2+
1
2
2+
1
2
2+
*1
*2
*3
*4
*5
*8
*9
*10
*11
*12
*13
0
1
0
1
0
1
0
1
0
*6
0
*7
0
(b)
0
(c)
word (AH) / byte (AL)
Quotient
→ byte (AL) Remainder →
byte (AH)
word (A) / byte (ear)
Quotient
→ byte (A) Remainder →
byte (ear)
word (A) / byte (eam)
Quotient
→ byte (A) Remainder →
byte (ear)
long (A) / word (eam)
Quotient
→ word (A) Remainder →
word (ear)
long (A) / word (eam)
Quotient
→ word (A) Remainder →
word (eam)
byte (AH) * byte (AL)
→ word (A)
byte (A) * byte (ear)
→ word (A)
byte (A) * byte (eam)
→ word (A)
word (AH) * word (AL)
→ Long (A)
word (A) * word (ear)
→ Long (A)
word (A) * word (eam)
→ Long (A)
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*
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*
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