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Mpysu, Multiply signed 16 lsb, Unsigned 16 lsb mpysu – Texas Instruments TMS320C67X/C67X+ DSP User Manual

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MPYSU

Multiply Signed 16 LSB x Unsigned 16 LSB

3-172

Instruction Set

SPRU733

Multiply Signed 16 LSB

y

Unsigned 16 LSB

MPYSU

Syntax

MPYSU (.unit) src1, src2, dst

.unit = .M1 or .M2

Compatibility

C62x, C64x, C67x, and C67x+ CPU

Opcode

31

29

28

27

23

22

18

17

13

12

11

7

6

5

4

3

2

1

0

creg

z

dst

src2

src1

x

op

0 0 0 0 0 s p

3

1

5

5

5

1

5

1

1

Opcode map field used...

For operand type...

Unit

Opfield

src1
src2
dst

slsb16
xulsb16
sint

.M1, .M2

11011

src1
src2
dst

scst5
xulsb16
sint

.M1, .M2

11110

Description

The signed operand src1 is multiplied by the unsigned operand src2. The result
is placed in dst. The S is needed in the mnemonic to specify a signed operand
when both signed and unsigned operands are used.

Execution

if (cond)

lsb16(src1) × lsb16(src2)

dst

else nop

Pipeline
Stage

E1

E2

Read

src1, src2

Written

dst

Unit in use

.M

Instruction Type

Multiply (16 × 16)

Delay Slots

1

Pipeline