/* Enables or disables the Internal High Speed oscillator (HSI).  */
void RCC_HSICmd(FunctionalState state)
/* Enables or disables the Internal High Speed oscillator (HSI).  */
void RCC_HSICmd(FunctionalState state)
{
    MODIFY_REG(RCC->CR, RCC_CR_HSION, (state << RCC_CR_HSION_Pos));
}