Mpyu//sub integer unsigned mpyu//sub, Multiply and subtract – Motorola DSP96002 User Manual

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MOTOROLA

Operation:

S1.L * S2.L

→

D1.M:D1.L

(parallel data bus move)

D2.L - S3.L

→

D2.L

MPYU//SUB Integer Unsigned MPYU//SUB

Multiply and Subtract

Description:

Multiply the two unsigned operands S1 and S2 and store the product in the specified destination register

D1. The two source operands S1and S2 are 32-bit integers and are taken from the low portion of S1 and

S2. The result is a 64-bit unsigned integer stored in the middle and low portions of D1.

Simultaneously, subtract the low portion of the specified source operand S3 from the low portion of the des-

tination operand D2 and store the result in the low portion of the destination operand D2.

This instruction is enabled only in Integer Mode.

Input Operand(s) Precision: 32-bit integer.

Subtraction Output Operand Precision: 32-bit integer.

Multiplication Output Operand Precision: 64-bit integer.

CCR Condition Codes:

- Set if borrow is generated from the MSB of the subtraction result. Cleared

otherwise.

- Set if the subtraction result overflows. Cleared otherwise.

- Set if result of the subtraction is zero. Cleared otherwise.

- Set if result of the subtraction is negative. Cleared otherwise.

- Not affected.

ER Status Bits: Not affected

IER Flags: Not affected

Assembler Syntax:

MPYU S1,S2,D1 SUB S3,D2

(move syntax - see the MOVE instruction de-

scription.)

MPYU S2,S1,D1 SUB S3,D2

(move syntax - see the MOVE instruction de-

scription.)