PORT and TIM issue with Discovery Board STM32F407

[9artus]

Posted on May 10, 2014 at 16:47

I am working on a sine wave program as a part of an Amateur Radio project.  I have a working code producing what I want using TIM3-- PWM and PORTC.  I am unfortunately unable to neither change the TIM3 to any other TIM nor am I able to change my PORTC to PORTE.  The code follows closely the PWM example by STM and Andrew Markham's approach to the interrupt handle.  I can post code, although I am not sure of the proper messaging protocol for code in this forum.  Since the code is working fine using TIM3 and PORTC, I would have thought that either change would have been a simple task.  I have of course tried to change only one at a time.  Changes compile fine with no errors;  but no output is found on the appropriate pin using an oscilloscope, except the TIM3/PORTC arrangement. Thanks for any help.

Jack (W0FNQ)

 

[Tesla DeLorean]

Posted on May 10, 2014 at 17:24

You can paste source using the Format Code Block (Paintbrush [<>] icon). I want to see complete compilable code.

Timers have specific pin utilization, so you can't randomly associate them. The part data sheet should show what routing options are available.

[9artus]

Posted on May 10, 2014 at 19:15

Thanks for reply. I am hoping to use TIM4 and PORTE pin 2. Here is the code:

* Jack Generaux (W0FNQ)
*
* Some concepts and sine table from:
******************************************************************************
* @file USART/main.c 
* @author Andrew Markham
* @version V1.0.0
* @date 27-April-2012
* @brief Main program body
******************************************************************************
*/ 
/* Includes ------------------------------------------------------------------*/
#include ''stm32f4xx_conf.h''
#include <
stdio.h
>
#include ''Oscillator.h''
#include ''stm32f4xx.h''
void PWM_Config(int period)
{
/* TIM3 clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM3, ENABLE);
/* GPIOC and GPIOB clock enable */
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC , ENABLE);
/* GPIOC Configuration: TIM3 CH1 (PC6) */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 ;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP ;
GPIO_Init(GPIOC, &GPIO_InitStructure);
/* Connect TIM3 pins to AF2 */
GPIO_PinAFConfig(GPIOC, GPIO_PinSource6, GPIO_AF_TIM3);
/* No prescale, run at maximum frequency */
uint16_t PrescalerValue=0;
/* Time base configuration */
TIM_TimeBaseStructure.TIM_Period = period;
TIM_TimeBaseStructure.TIM_Prescaler = PrescalerValue;
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM3, &TIM_TimeBaseStructure);
/* PWM1 Mode configuration: Channel1 */
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_Pulse = 0;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Disable;
TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Reset;
TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCNIdleState_Reset;
TIM_OC1Init(TIM3, &TIM_OCInitStructure);
TIM_OC1PreloadConfig(TIM3, TIM_OCPreload_Enable);
TIM_ARRPreloadConfig(TIM3, ENABLE);
/* TIM3 enable counter */
TIM_Cmd(TIM3, ENABLE);
}
void PWM_SetDC(uint16_t dutycycle)
{
TIM3->CCR1 = dutycycle;
}
void INTTIM_Config(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
/* Enable the TIM2 gloabal Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
/* TIM2 clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
/* Time base configuration */
TIM_TimeBaseStructure.TIM_Period = 10 - 1; // 1 MHz down to 100 KHz
TIM_TimeBaseStructure.TIM_Prescaler = 84 - 1;
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
/* TIM IT enable */
TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
/* TIM2 enable counter */
TIM_Cmd(TIM2, ENABLE);
}
void TIM2_IRQHandler(void)
{
if (TIM_GetITStatus(TIM2, TIM_IT_Update) != RESET)
{
PWM_SetDC(pulse_width);
// Calculate a new pulse width
phase_accumulator+=R;
angle=(uint8_t)(phase_accumulator>>24);
pulse_width = sinetable[angle];
TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
}

[Tesla DeLorean]

Posted on May 10, 2014 at 20:53

PE2 has no timer associativity. Please refer to the

http://www.st.com/st-web-ui/static/active/en/resource/technical/document/datasheet/DM00037051.pdf

for your part.

PE5/PE6 are TIM9_CH1 and CH2 respectively

[9artus]

Posted on May 10, 2014 at 21:13

thanks for the reference pointer.  I will explore other possible combinations.