Texas Instruments TMS320C2XX User Manual

Page 295

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RET

Return From Subroutine

7-142

Syntax

RET

Operands

None

Opcode

0

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

0

0

0

0

0

0

0

0

1

1

1

1

0

1

1

1

Execution

(TOS)

PC

Pop stack one level.

Status Bits

None

Description

The contents of the top stack register are copied into the program counter. The
remaining stack values are then copied up one level. RET concludes subrou-
tines and interrupt service routines to return program control to the calling or
interrupted program sequence.

Words

1

Cycles for a Single RET Instruction

ROM

DARAM

SARAM

External

4

4

4

4+3p

Note:

When this instruction reaches the execute phase of the pipeline, two additional instruc-
tion words have entered the pipeline. When the PC discontinuity is taken, these two
instruction words are discarded.

Example

RET

Before Instruction

After Instruction

PC

96h

PC

37h

Stack

37h

Stack

45h

45h

75h

75h

21h

21h

3Fh

3Fh

45h

45h

6Eh

6Eh

6Eh

6Eh

6Eh

Cycles

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