请教关于2个32位变量软件实现64位变量的算法 IAR STM8
请教关于2个32位变量软件实现64位变量的算法static uint32_t bmp280_compensate_pressure_int64(struct bmp280 *bmp280, int32_t adc_P)
{
int64_t var1, var2, pressure;
var1 = ((int64_t)bmp280->t_fine) - 128000;
var2 = var1 * var1 * (int64_t)dig_P6;
var2 = var2 + ((var1*(int64_t)dig_P5)<<17);
var2 = var2 + (((int64_t)dig_P4)<<35);
var1 = ((var1 * var1 * (int64_t)dig_P3)>>8) + ((var1 * (int64_t)dig_P2)<<12);
var1 = (((((int64_t)1)<<47)+var1))*((int64_t)dig_P1)>>33;
if (var1 == 0)
{
return 0; // avoid exception caused by division by zero
}
pressure = 1048576-adc_P;
pressure = (((pressure<<31)-var2)*3125)/var1;
var1 = (((int64_t)dig_P9) * (pressure>>13) * (pressure>>13)) >> 25;
var2 = (((int64_t)dig_P8) * pressure) >> 19;
pressure = ((pressure + var1 + var2) >> 8) + (((int64_t)dig_P7)<<4);
return (uint32_t)pressure;
}
以上程序在iarstm32上运行正常，但是在iar stm8上不支持64位的变量
真的非常复杂，建议你直接参考现成的例子。实现除法你就要崩溃了
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