STM32F051 Timer1 PWM Output

Hallo

Ich habe aus dem ST Lib den Code für Timer1 genommen, um an 4 Outputs 
(CH1, CH1N, CH2, CH2N) ein PWM Signal für eine H-Brücke zu erzeugen.
Aber irgendwie läuft der Timer nicht. Timer14 läuft, das heisst der 
Prozessor funktioniert. Was ist daran falsch, ich finde den Fehler 
einfach nicht:

  TimerPeriod = (SystemCoreClock / 17570) - 1;

  /* Compute CCR1 value to generate a duty cycle at 50% for channel 1 */
  Channel1Pulse = (uint16_t) (((uint32_t) 50 * (TimerPeriod - 1)) / 
100);

  /* Compute CCR2 value to generate a duty cycle at 25%  for channel 2 
*/
  Channel2Pulse = (uint16_t) (((uint32_t) 25 * (TimerPeriod - 1)) / 
100);

  /* Time Base configuration */
  TIM_TimeBaseStructure.TIM_Prescaler = 1;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseStructure.TIM_Period = TimerPeriod;
  TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;;
  TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;

  TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);

  /* Channel 1, 2 Configuration in PWM mode */
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Enable;
  TIM_OCInitStructure.TIM_Pulse = Channel1Pulse;
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;
  TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_Low;
  TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;
  TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;

  TIM_OC1Init(TIM1, &TIM_OCInitStructure);

  TIM_OCInitStructure.TIM_Pulse = Channel2Pulse;
  TIM_OC2Init(TIM1, &TIM_OCInitStructure);

  /* Automatic Output enable, Break, dead time and lock configuration*/

  TIM_BDTRInitStructure.TIM_OSSRState = TIM_OSSRState_Enable;
  TIM_BDTRInitStructure.TIM_OSSIState = TIM_OSSIState_Enable;
  TIM_BDTRInitStructure.TIM_LOCKLevel = TIM_LOCKLevel_1;
  TIM_BDTRInitStructure.TIM_DeadTime = 11;
  TIM_BDTRInitStructure.TIM_Break = TIM_Break_Disable;
  //TIM_BDTRInitStructure.TIM_BreakPolarity = TIM_BreakPolarity_High;
  TIM_BDTRInitStructure.TIM_AutomaticOutput = 
TIM_AutomaticOutput_Enable;

  TIM_BDTRConfig(TIM1, &TIM_BDTRInitStructure);

  /* TIM1 counter enable */
  TIM_Cmd(TIM1, ENABLE);

  /* Main Output Enable */
  TIM_CtrlPWMOutputs(TIM1, ENABLE);