PM0214 datasheet(126/245 Pages) STMICROELECTRONICS

126 / 245 page

The STM32 Cortex-M4 instruction set

PM0214

126/245

DocID022708 Rev 4

3.7.2

SSAT16 and USAT16

Signed Saturate and Unsigned Saturate to any bit position for two halfwords.

Syntax

op{cond} Rd, #n, Rm

where:

•

op’ is one of:

SSAT16 Saturates a signed halfword value to a signed range.

USAT16 Saturates a signed halfword value to an unsigned range.

•

‘cond’ is an optional condition code (see Conditional execution on page 64)

•

‘Rd’ is the destination register.

•

‘n’ specifies the bit position to saturate to:

n ranges from 1 to 16 for SSAT.

n ranges from 0 to 15 for USAT.

•

‘Rm’ is the register containing the value to saturate.

Operation

The SSAT16 instruction:

Saturates two signed 16-bit halfword values of the register with the value to saturate

from selected by the bit position in n.

Writes the results as two signed 16-bit halfwords to the destination register.

The USAT16 instruction:

Saturates two unsigned 16-bit halfword values of the register with the value to saturate

from selected by the bit position in n.

Writes the results as two unsigned halfwords in the destination register.

Restrictions

Do not use SP and do not use PC.

Condition flags

These instructions do not affect the condition code flags.

If saturation occurs, these instructions set the Q flag to 1.

Examples

SSAT16

R7, #9, R2

; Saturates the top and bottom highwords of R2

; as 9-bit values, writes to corresponding halfword

; of R7

USAT16NE

R0, #13, R5

; Conditionally saturates the top and bottom

; halfwords of R5 as 13-bit values, writes to

; corresponding halfword of R0.

PM0214 датащи(PDF) 126 Page - STMicroelectronics

PM0214 датащи(HTML) 126 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

датащи скачать

ссылки URL