/* Enables or disables the TIM Capture Compare Channel xN.  */
void TIM_CCxNCmd(TIM_TypeDef *TIMx, uint16_t TIM_Channel, uint16_t TIM_CCxN)
/* Enables or disables the TIM Capture Compare Channel xN.  */
void TIM_CCxNCmd(TIM_TypeDef *TIMx, uint16_t TIM_Channel, uint16_t TIM_CCxN)
{
    assert_param(IS_TIM_18_PERIPH(TIMx));
    assert_param(IS_TIM_COMPLEMENTARY_CHANNEL(TIM_Channel));
    assert_param(IS_TIM_CCXN(TIM_CCxN));
    TIMx->CCER &= (uint16_t)(~((uint16_t)(CCER_CCNE_Set << TIM_Channel))); 
    TIMx->CCER |=  (uint16_t)(TIM_CCxN << TIM_Channel);
}