Step 1: System Timer and Execution Cycles
System Timer SysTick
The SysTick system timer is a 24-bit core timer integrated into Arm® Cortex®-M microcontrollers and is used to generate periodic timing events. It operates as a down-counter, driven by either the processor clock or a prescaled reference clock. When the counter reaches zero, the SysTick timer generates an interrupt, indicating a periodic timeout condition. This interrupt is commonly employed for delay generation, system time-base creation, and scheduler tick implementation. SysTick provides a simple, reliable, and efficient timing mechanism for embedded system applications.
Execution Cycles for Microcontrollers
Execution cycles indicate the number of CPU clock cycles required to complete a specific instruction or operation.
The total cycle count is determined by factors such as instruction complexity, memory access latency, and the architecture of the microcontroller core.
Arithmetic operations, including assignment, multiplication, and division, consume varying numbers of clock cycles depending on their computational requirements.
Measuring execution cycles allows for accurate performance evaluation of embedded applications.
Analyzing cycle counts supports software optimization, leading to improved execution speed and more efficient resource utilization.