Posted on July 02, 2014 at 14:34
hello dear forum
I drive an H bridge with STM32F103
I want that until I enable the H bridge the PWM outputs to be low
( I runbelow reset_motor() function until motor enabled )
however the Upper mosfets are driven with logic 1 until I enable the motor
here is my code
please which lines to be changed how ?
thank you
void
PWMinit2(
void
){
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6|GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_Init(GPIOC, &GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_2MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
/* Time Base configuration */
TIM_TimeBaseStructure.TIM_Prescaler = 99;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseStructure.TIM_Period = 7200;
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;
TIM_TimeBaseInit(TIM8, &TIM_TimeBaseStructure);
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 = 6000;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;
TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Reset;
TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCNIdleState_Reset;
TIM_OC1Init(TIM8, &TIM_OCInitStructure);
TIM_OC2Init(TIM8, &TIM_OCInitStructure);
reset_motor();
/* 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_OFF;
TIM_BDTRInitStructure.TIM_DeadTime = 120;
TIM_BDTRInitStructure.TIM_Break = TIM_Break_Disable;
TIM_BDTRInitStructure.TIM_BreakPolarity = TIM_BreakPolarity_Low;
TIM_BDTRInitStructure.TIM_AutomaticOutput = TIM_AutomaticOutput_Disable;
TIM_BDTRConfig(TIM8, &TIM_BDTRInitStructure);
TIM_CCPreloadControl(TIM8, DISABLE);
TIM_ARRPreloadConfig(TIM8, ENABLE);
TIM_ITConfig(TIM8, TIM_IT_Update , ENABLE);
/* TIM1 counter enable */
TIM_Cmd(TIM8, ENABLE);
/* Main Output Enable */
TIM_CtrlPWMOutputs(TIM8, ENABLE);
reset_motor();
}
void
reset_motor(
void
){
TIM_CCxCmd(TIM8, TIM_Channel_1, TIM_CCx_Disable);
TIM_CCxNCmd(TIM8, TIM_Channel_1, TIM_CCxN_Disable);
TIM_CCxCmd(TIM8, TIM_Channel_2, TIM_CCx_Disable);
TIM_CCxNCmd(TIM8, TIM_Channel_2, TIM_CCxN_Disable);
}
