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66 shl shift left – Texas Instruments MSP50C6xx User Manual

Page 248

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Individual Instruction Descriptions

4-162

4.14.66

SHL

Shift Left

Syntax

[label]

name

dest [, mod]

Clock, clk

Word, w

With RPT, clk

Class

SHL

An[~] [, next A]

1

1

n

R

+3

3

Execution

[premodify AP if mod specified]
PH, PL

src << SV

PC

PC + 1

Flags Affected

OF, SF, ZF, CF are set accordingly

Opcode

Instructions

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

SHL An[~] [, next A]

1

1

1

0

0

next A

An

1

1

1

1

1

0

A~

0

Description

Premodify the accumulator pointer if specified. Shift accumulator word left n

SV

bits (as specified by the SV register) into a 32-bit result. This result is zero-filled
or sign-extended on the left (based on the setting of the extended sign mode
(XM) bit in the status register). The upper 16 bits are latched into the PH
register. Accumulator content is not changed. The lower 16-bit value, PL, is
discarded. The SHL instruction can be used with a RPT instruction, but without
much advantage since the instruction does not write back into the
accumulator. Use SHLAC for this purpose.

See Also

SHLS

Example 4.14.66.1

SHL A0, ++A

Preincrement accumulator pointer AP0. Shift accumulator word A0 to the left by SV bits. Accumulator
content is not changed. PH contains the upper 16 bits of the shifted result.