Требуется программист в Зеленограде
- обработка данных с датчиков; ColdFire; 40 тыс. e-mail:jobsmp@pochta.ru |
//Division by constants//////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/** \brief unsigned 8-bit division by 5 (using shifts)
äåëåíèå áåççíàêîâîãî 8-áèòíîãî ÷èñëà íà 5 (åñëè íåò àïïàðàòíîãî óìíîæåíèÿ) \ingroup group_math */
u8 div_by5_u8_soft(u8 data_in)
{u16 u16_01, result;
result = u16_01 = data_in;
u16_01 <<= 1;
result += u16_01;
u16_01 <<= 1; u16_01 <<= 1; u16_01 <<= 1;
result += u16_01;
u16_01 <<= 1;
result += u16_01;
result += 51;
return(result >> 8);
}/** \brief unsigned 8-bit division by 5 (using multiply)
äåëåíèå áåççíàêîâîãî 8-áèòíîãî ÷èñëà íà 5 (åñëè åñòü àïïàðàòíîå óìíîæåíèå) \ingroup group_math */
u8 div_by5_u8_hmul(u8 data_in)
{return((((u16)data_in * 0x33) + 0x33) >> 8);
}/** \brief unsigned 16-bit division by 5 (using shifts)
äåëåíèå áåççíàêîâîãî 16-áèòíîãî ÷èñëà íà 5 (åñëè íåò àïïàðàòíîãî óìíîæåíèÿ) \ingroup group_math */
u16 div_by5_u16_soft(u16 data_in)
{u32 u32_01, result;
result = u32_01 = data_in;
u32_01 <<= 1; result += u32_01;
u32_01 <<= 3; result += u32_01;
u32_01 <<= 1; result += u32_01;
u32_01 <<= 3; result += u32_01;
u32_01 <<= 1; result += u32_01;
u32_01 <<= 3; result += u32_01;
u32_01 <<= 1; result += u32_01;
result += 0x3333;
return(result >> 16);
}/** \brief unsigned 16-bit division by 5 (using multiply) \ingroup group_math */
u16 div_by5_u16_hmul(u16 data_in)
{return((((u32)data_in * 0x3333) + 0x3333) >> 16);
}