IDEC FC4A-C10R2 User Manual page 237

Repeat Operation in the MUL Instruction
Since the MUL (multiplication) instruction uses two destination operands, the result is stored to destination operands as
described below. Source operands S1 and S2 and destination operand D1 can be designated to repeat individually or in
combination. When destination operand D1 is not designated to repeat, the final result is set to destination operand D1 and
D1+1. When repeat is designated, consecutive operands as many as the repeat cycles starting with the designated operand
are used.
Since the repeat operation works similarly on the word and integer data types, the following examples are described using
the word data type.
Repeat One Source Operand
When only S1 (source) is designated to repeat, the final result is set to destination operands D1 and D1+1.
MUL(W)
SOTU
I1
Repeat Destination Operand Only
When only D1 (destination) is designated to repeat, the same result is set to 6 operands starting with D1.
MUL(W)
SOTU
I1
Repeat Two Source Operands
When S1 and S2 (source) are designated to repeat, the final result is set to destination operands D1 and D1+1.
MUL(W)
SOTU
I1
Repeat Source and Destination Operands
When S1 (source) and D1 (destination) are designated to repeat, different results are set to 6 operands starting with D1.
MUL(W)
SOTU
I1
Repeat All Source and Destination Operands
When all operands are designated to repeat, different results are set to 6 operands starting with D1.
MUL(W)
SOTU
I1
S1 R S2 – D1 –
D10 D20 D30
S1 – S2 – D1 R
D10 D20 D30
S1 R S2 R D1 –
D10 D20 D30
S1 R S2 – D1 R
D10 D20 D30
S1 R S2 R D1 R
D10 D20 D30
« FC4A M
ICRO
11: B
S1 (Repeat = 3)
REP
D10
3
D11
D12
S1 (Repeat = 0)
REP
D10
3
D10
D10
S1 (Repeat = 3)
REP
D10
3
D11
D12
S1 (Repeat = 3)
REP
D10
3
D11
D12
S1 (Repeat = 3)
REP
D10
3
D11
D12
S U ' M »
MART SER S ANUAL
A
INARY RITHMETIC
S2 (Repeat = 0)
×
D20 (D30)
×
D20 (D30)
×
D20
S2 (Repeat = 0)
×
D20
×
D20
×
D20
S2 (Repeat = 3)
×
D20 (D30)
×
D21 (D30)
×
D22
S2 (Repeat = 0)
×
D20
×
D20
×
D20
S2 (Repeat = 3)
×
D20
×
D21
×
D22
I
NSTRUCTIONS
D1 (Repeat = 0)
(D31)
(D31)
D30 D31
D1 (Repeat = 3)
D30 D31
D32 D33
D34 D35
D1 (Repeat = 0)
(D31)
(D31)
D30 D31
D1 (Repeat = 3)
D30 D31
D32 D33
D34 D35
D1 (Repeat = 3)
D30 D31
D32 D33
D34 D35
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