Texas Instruments TMS320C67X/C67X+ DSP manual MPY Multiply Signed 16 LSB x Signed 16 LSB

MPY Multiply Signed 16 LSB x Signed 16 LSB

Example 1 MPY .M1 A1,A2,A3

Before instruction

2 cycles after instruction

A1 0000 0123h

A2 01E0 FA81h

A3 xxxx xxxxh

†Signed 16-LSB integer

291†A1

−1407†A2 A3

0000 0123h
01E0 FA81h
FFF9 C0A3	−409437

Example 2	MPY .M1		13,A1,A2
		Before instruction
	A1			−13†	A1
		3497 FFF3h
	A2	xxxx xxxxh			A2

†Signed 16-LSB integer

2 cycles after instruction

3497 FFF3h
FFFF FF57h	−163

3-144 Instruction Set SPRU733