Posted on February 23, 2014 at 19:14Hello,
I use TIM1 to generate a clock-signal at the gpio-output-pin TIM1_CH1. This signal will be generated until a rising edge is detected at TIM_ETR (gpio-input). So the output-signal will be immediately pulled down to low as you can see in screenshot (after a detected TIM_ETR). So far, so good.
This really short pulse with an immediately low after the rising edge is to fast (you can see it in the attatched screenshot). So I try to expand/stretch the last pulse with a dead-time insertion. But this is not working at me.
I hope somebody can hint me.
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
TIM_BDTRInitTypeDef TIM_BDTRInitStructure;
/* TIM DISABLE counter */
TIM_Cmd(TIM1, DISABLE);
/* System Clocks Configuration */
/* TIM1 clock enable */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1, ENABLE);
/* Time base configuration */
TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
TIM_TimeBaseStructure.TIM_Period = 72;
TIM_TimeBaseStructure.TIM_Prescaler = 0;
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);
/* Output Compare Toggle Mode configuration: Channel1 */
TIM_OCStructInit(&TIM_OCInitStructure);
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_Toggle;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
TIM_OC1Init(TIM1, &TIM_OCInitStructure);
/* enable the choose to stop the timer on rising/falling edge at external
* pin PA12 (=CAM_READ) */
TIM_ClearOC1Ref (TIM1, TIM_OCClear_Enable);
TIM_ETRConfig (TIM1, TIM_ExtTRGPSC_OFF, TIM_ExtTRGPolarity_NonInverted, 0);
/* down HERE !!! seems to be my problem ??? */
/* ==================> */
/* Automatic Output enable, Break, dead time and lock configuration*/
TIM_BDTRStructInit(&TIM_BDTRInitStructure);
TIM_BDTRInitStructure.TIM_OSSRState = TIM_OSSRState_Disable;//TIM_OSSRState_Enable;
TIM_BDTRInitStructure.TIM_OSSIState = TIM_OSSIState_Enable;
TIM_BDTRInitStructure.TIM_LOCKLevel = TIM_LOCKLevel_OFF;
TIM_BDTRInitStructure.TIM_DeadTime = 72;
TIM_BDTRInitStructure.TIM_Break = TIM_Break_Disable;
TIM_BDTRInitStructure.TIM_BreakPolarity = TIM_BreakPolarity_Low;
TIM_BDTRInitStructure.TIM_AutomaticOutput = TIM_AutomaticOutput_Enable;
TIM_BDTRConfig(TIM1, &TIM_BDTRInitStructure);
TIM_OC1PreloadConfig(TIM1, TIM_OCPreload_Disable);
TIM_CtrlPWMOutputs(TIM1, ENABLE);
}
