Mastering Input Capture in STM32H563 Microcontrollers

2025-05-09 embedded

Paris, Friday, 9 May 2025.
Learn how the STM32H563 microcontroller uses input capture to precisely measure signal frequency and pulse width. Understand core components, configuration techniques, and troubleshooting steps.

Core Components and Configuration

The STM32H563’s input capture system comprises three essential elements: the timer counter, capture/compare register (CCR), and input capture channel [1]. The system operates at a base clock frequency of 125 MHz, with the timer connected to APB1, enabling precise measurement of external signals [1]. Engineers can configure key parameters including edge selection, prescaler settings, and filtering options to optimize capture performance [1].

Advanced Implementation Techniques

For high-frequency applications, direct interrupt-based capture methods may prove insufficient due to CPU overhead. A more efficient approach involves utilizing DMA (Direct Memory Access) for automated data collection [2]. This method is particularly valuable when measuring multiple pulse intervals within specific time windows, preventing task starvation in resource-constrained systems [2]. The latest implementations demonstrate success with signals requiring timing resolution as precise as 60 nanoseconds per bit [4].

Practical Applications and Performance

In real-world applications, the input capture feature proves invaluable for precise timing measurements. The STM32H563 can achieve a timing resolution of 8 microseconds with appropriate prescaler configuration [1]. Modern biomedical applications showcase practical implementations, such as temperature control systems utilizing timer-based measurements for precise monitoring [7]. These applications demonstrate the versatility of input capture in mission-critical scenarios.

Optimization and Troubleshooting

Recent developments in timer configuration strategies show that optimal performance requires careful consideration of prescaler values and interrupt handling [6]. For applications requiring maximum precision, the timer can be configured with a prescaler of 124 and an auto-reload register value of 999, achieving a precise 1 ms period [1]. Engineers should note that system performance may be limited by interrupt latency, particularly in high-frequency applications [4].

sources

STM32 Input Capture