DSP Core Instruction Set

A.1.2 Addressing Mode Notation

Table A-5 and Table A-6 define the fields in the address offset or post increment tables, which are found in the instruction field section of an instruction definition. EA stands for effective address. A different field in the opcode (RRR) determines what register is used for Rn.

EA

 

MMM

 

Effective Address Notation

 

 

 

 

000

(Rn+N0)

010

(Rn)

100

(Rn)+N0

110

(Rn)+N2

 

 

 

 

 

 

 

 

 

 

 

 

 

001

(Rn)–

011

(Rn)+

101

(Rn)+N1

111

(Rn)+N3

 

 

 

 

 

 

 

 

Table A-5. Addressing Mode Notation for the EA Operand

 

 

 

 

 

 

 

 

 

 

Addressing Mode Definition

Notation in the Instruction Field

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Indexed by offset in N0

 

(Rn + N0)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Post decrement

 

(Rn)–

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

No update

 

(Rn)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Post increment

 

(Rn)+

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Post update by offset in N0

 

(Rn) + N0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Post update by offset in N1

 

(Rn) + N1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Post update by offset in N2

 

(Rn) + N2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Post update by offset in N3

 

(Rn) + N3

 

 

 

 

 

 

 

 

 

 

 

 

 

Note:

Rn is taken from the Rn (RRR) table found in the instruction definition.

 

 

 

 

ea

 

MM

 

Effective Address Notation

 

 

00 (Rn)+

01 (Rn)–

10 (Rn+N0)

11 (Rn)

Table A-6. Addressing Mode Notation for the ea Operand

Addressing Mode Definition

Notation in Instruction Field

 

 

 

 

Indexed by offset in N0

(Rn + N0)

 

 

Post decrement

(Rn)–

 

 

No update

(Rn)

 

 

Post increment

(Rn)+

 

 

Note: Rn is taken from the Rn (RRR) table found in the instruction definition.

SC140 DSP Core Reference Manual

A-5

Page 319
Image 319
Freescale Semiconductor SC140 specifications Addressing Mode Notation, Effective Address Notation