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69 shlapl shift left with accumulate – Texas Instruments MSP50C6xx User Manual

Page 251

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Individual Instruction Descriptions

4-165

Assembly Language Instructions

4.14.69

SHLAPL

Shift Left with Accumulate

Syntax

[label]

name

dest, src

[, mod]

Clock, clk

Word, w

With RPT, clk

Class

SHLAPL

An, {adrs}

Table 4–46

Table 4–46

1b

SHLAPL

An[~], An[~] [, next A]

1

1

n

R

+3

3

Execution

[premodify AP if mod specified]
PH, PL

src << SV

dest

dest + PL

PC

PC + 1

Flags Affected

OF, SF, ZF, CF are set accordingly
src is {adrs}:

TAG bit is set accordingly

Opcode

Instructions

16

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

SHLAPL An, {adrs}

0

1

1

1

1

0

0

An

adrs

x

dma16 (for direct) or offset16 (long relative) [see section 4.13]

SHLAPL An[~], An[~] [, next A]

1

1

1

0

0

next A

An

1

1

1

0

1

0

A~

~A

Description

Premodify the accumulator pointer if specified. Shift accumulator word or data memory
word pointed by {adrs} to left n

SV

bits (as specified by the SV register) into a 32-bit

result. This result is zero-filled on the right and either 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 product high (PH) register. The lower 16 bits of
the result [product low (PL) register] is added to the destination accumulator (or its
offset). This instruction propagates the shifted bits to the next accumulator.

Syntax

Description

SHLAPL An, {adrs}

Shift data memory word left, add PL to An

SHLAPL An[~], An[~] [, next A]

Shift An[~] left, add PL to An[~]

See Also

SHLAPLS, SHLTPL , SHLTPLS, SHLSPL, SHLSPLS

Example 4.14.69.1

SHLAPL A0, *R4++R5

Shift the word pointed by the byte address stored in R4 by n

SV

bits to the left, add the shifted value (PL)

with accumulator A0, store the result in accumulator A0. Add R5 to R4 and store result in R4. PH holds
the upper 16 bits of the shift.

Example 4.14.69.2

SHLAPL A2, *R1++

Shift the word pointed by the byte address stored in R1 by n

SV

bits to the left, add the shifted value (PL)

with the accumulator (A2), and store the result in accumulator A2. Increment R1 (by 2) . PH holds the
upper 16 bits of the shift.

Example 4.14.69.3

SHLAPL A1, A1, ++A

Preincrement accumulator pointer AP1. Shift the accumulator A1 by n

SV

bits to the left, add the shifted

value (PL) to the accumulator and store the result in accumulator (A1). After execution PH contains the
upper 16 bits of the 32-bit shift.