PM0214 datasheet(152/245 Pages) STMICROELECTRONICS

152 / 245 page

The STM32 Cortex-M4 instruction set

PM0214

152/245

DocID022708 Rev 4

3.10.5

VCVT between floating-point and fixed-point

Converts a value in a register from floating-point to and from fixed-point.

Syntax

VCVT{cond}.Td.F32 Sd, Sd, #fbits

VCVT{cond}.F32.Td Sd, Sd, #fbits

where:

•

‘cond’ is an optional condition code, see Conditional execution on page 64.

•

‘Td’ is the data type for the fixed-point number. It must be one of:

S16

signed 16-bit value.

U16

unsigned 16-bit value.

S32

signed 32-bit value.

U32

unsigned 32-bit value.

•

‘Sd’ is the destination register and the operand register.

•

‘fbits’ is the number of fraction bits in the fixed-point number:

If Td is S16 or U16, fbits must be in the range 0-16.

I f Td is S32 or U32, fbits must be in the range 1-32.

Operation

These instructions:

Either

Converts a value in a register from floating-point to fixed-point.

Converts a value in a register from fixed-point to floating-point.

Places the result in a second register.

The floating-point values are single-precision.

The fixed-point value can be 16-bit or 32-bit. Conversions from fixed-point values take their

operand from the low-order bits of the source register and ignore any remaining bits.

Signed conversions to fixed-point values sign-extend the result value to the destination

Unsigned conversions to fixed-point values zero-extend the result value to the destination

The floating-point to fixed-point operation uses the Round towards Zero rounding mode.

The fixed-point to floating-point operation uses the Round to Nearest rounding mode.

Restrictions

There are no restrictions.

Condition flags

These instructions do not change the flags.

PM0214 датащи(PDF) 152 Page - STMicroelectronics

PM0214 датащи(HTML) 152 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