This document provides an overview of a training on timers and PWM for bare metal embedded systems. The goals are to learn clock control, generate 1Hz signals using delays and timers, and create PWM signals at predefined duty cycles. It explains clock control diagrams and settings, and provides code examples to generate a 1Hz signal using delays, use Timer4 to toggle a pin in an interrupt handler, and set up PWM on Timer4 Channel 3. Finally, it lists an individual task to control 4 LEDs with PWM using different channels and buttons to fade the LEDs in/out.

1. GlobalLogic
Embedded Starter
Kit
Timers and PWM
Training 03
Bare Metal
Trainings

2. Contents
▪ Assignments and Goals
▪ Theory
▪ Practice
▪ Individual task
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3. Assignments and Goals
• Learn about clock control
• Create firmware that generate 1Hz signal
• Create firmware that works with Timers to
generate signals
• Create firmware that generate PWM signal
with predefined duty cycle
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4. Clock control diagram
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5. Clock control settings
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6. Clock control settings
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7. Create FW that generates 1Hz signal
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/* Infinite loop */
/* USER CODE BEGIN WHILE */
while (1)
{
HAL_Delay(500);
HAL_GPIO_TogglePin(GPIOD, GPIO_PIN_13);
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */

8. Create FW that generates 1Hz signal
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9. Timers
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10. Timer4 diagram
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11. Create FW that work with Timer4
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12. Create FW that work with Timer4
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13. Create FW that work with Timer4
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In main()
{
HAL_TIM_Base_Start_IT(&htim4);
while (1) {}
}
void TIM4_IRQHandler(void)
{ /* USER CODE BEGIN TIM4_IRQn 0 */
HAL_GPIO_TogglePin(GPIOD, GPIO_PIN_15);
/* USER CODE END TIM4_IRQn 0 */
HAL_TIM_IRQHandler(&htim4);
/* USER CODE BEGIN TIM4_IRQn 1 */
/* USER CODE END TIM4_IRQn 1 */
}

14. Create FW that work with Timer4
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15. Create FW that work with PWM
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16. Create FW that work with PWM
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In main()
{
HAL_TIM_PWM_Start(&htim4, TIM_CHANNEL_3);
TIM4->CCR3=100;
while (1)
{}
}

17. Create FW that work with PWM
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18. Individual task
• Enable 4 PWMs to control LEDs
(PD15, PD14, PD13, PD12)
• Blink LED without interrupts and main loop
(by timer HW)
• Fade In/Out LEDs with help of buttons
(or automatically by algorithm)
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