Hello forum, The processor is STM32F072 I got a download of a code snippet that I want to modify. It works great on PA8. I want the same PWM output on PA9 and PA10. I tried several things but none worked. Here is the code snippet /* (1) Enable the

[David Blight]

Posted on March 23, 2017 at 00:15

Hello forum,

The processor is STM32F072

I got a download of a code snippet that I want to modify.  It works great on PA8.  I want the same PWM output on PA9 and PA10.  I tried several things but none worked.  Looking for suggestions

Here is the code snippet

/* (1) Enable the peripheral clock of Timer x */

/* (2) Enable the peripheral clock of GPIOA */

/* (3) Select alternate function mode on GPIOA pin 8*/

/* (4) Select AF2 on PA8 in AFRH for TIM1_CH1 */

RCC->APB2ENR |= RCC_APB2ENR_TIM1EN; /* (1) */

RCC->AHBENR |= RCC_AHBENR_GPIOAEN; /* (2) */

GPIOA->MODER = (GPIOA->MODER & ~(GPIO_MODER_MODER8)) | (GPIO_MODER_MODER8_1);/* (3) */

GPIOA->AFR[1] |= 0x02; /* (4) */

/* (1) Set prescaler to xx, so APBCLK/48 i.e 48 MHz */

/* (2) Set ARR = 200, as timer clock is 1MHz the period is 50 us */

/* (3) Set CCRx = x, , the signal will be high during 0-199 steps */

/* (4) Select PWM mode 1 on OC1 (OC1M = 110),

enable preload register on OC1 (OC1PE = 1) */

/* (5) Select active high polarity on OC1 (CC1P = 0, reset value),

enable the output on OC1 (CC1E = 1)*/

/* (6) Enable output (MOE = 1)*/

/* (7) Enable counter (CEN = 1)

select edge aligned mode (CMS = 00, reset value)

select direction as upcounter (DIR = 0, reset value) */

/* (8) Force update generation (UG = 1) */

TIMx->PSC = 1; /* (1) */

TIMx->ARR = 200; /* (2) */

TIMx->CCR1 = 25; /* (3) */

TIMx->CCMR1 |= TIM_CCMR1_OC1M_2 | TIM_CCMR1_OC1M_1 | TIM_CCMR1_OC1PE; /* (4) */

TIMx->CCER |= TIM_CCER_CC1E; /* (5) */

TIMx->BDTR |= TIM_BDTR_MOE; /* (6) */

TIMx->CR1 |= TIM_CR1_CEN; /* (7) */

TIMx->EGR |= TIM_EGR_UG; /* (8) */

#pwm-timer-output

[waclawek.jan]

Posted on March 23, 2017 at 02:19

I tried several things but none worked.  

Namely?

JW

[NPate.1]

If you want to download STM32F072 processor, you may use https://hpsupports.co/hp-customer-support/ and from here, you are able to get the features and the future scopes for the processor And if you want to update the processor, you can use the link.

[henry.dick]

" It works great on PA8. I want the same PWM output on PA9 and PA10."

simple:

1) understand how the previous code works;

2) replicate that on your new target.

whether you can remap the output to PA9/PA10 will be chip-dependent. check the datasheet to be sure.