Motorola DSP56000, 24-Bit Digital Signal Processor manual Xea, expr

INSTRUCTION DESCRIPTIONS

DO	Start Hardware Loop
Instruction Format:
DO	X:ea, expr
DO	Y:ea, expr

Opcode:

DO

	23	20	19	16	15	8	7	0
0 0 0 0			0 1 1 0		0 1 M M	M R R R	0 S 0 0	0 0 0 0

ABSOLUTE ADDRESS EXTENSION

Instruction Fields:

ea=6-bit Effective Address=MMMRRR, expr=16-bit Absolute Address in 24-bit extension word

Effective
Addressing Mode	M M M R R R						Memory SpaceS
(Rn)-Nn	0	0	0	r	r	r	X Memory	0
(Rn)+Nn	0	0	1	r	r	r	Y Memory	1
(Rn)-	0	1	0	r	r	r
(Rn)+	0	1	1	r	r	r
(Rn)	1	0	0	r	r	r
(Rn+Nn)	1	0	1	r	r	r
-(Rn)	1	1	1	r	r	r

where “rrr” refers to an address register R0-R7

Timing: 6+mv oscillator clock cycles

Memory: 2 program words

MOTOROLA INSTRUCTION SET DETAILS A - 93