🚀 Understanding SysTick Timer, ISRs, and Clock Cycles in Embedded Systems!
After diving deep into how the SysTick timer and interrupts work in embedded systems, I finally had a breakthrough in understanding how they operate independently of the main program!
Here’s a summary of what I learned:
🔧 SysTick is hardware-based and keeps running as long as the system clock is active. Whether your program is in a busy state (like a while(1) loop) or not, SysTick keeps counting clock cycles (e.g., every 16,000 clock cycles for a 1 ms interval on a 16 MHz clock).
⏳ ISR (Interrupt Service Routine), like the SysTick_Handler, is triggered by SysTick when it reaches 0 and needs to be reloaded. It runs independently, whether the main loop is busy or not. This makes the system efficient, allowing the ISR to manage tasks like incrementing a tick counter.
💡 What’s amazing is that, during a function like BSP_delay(), we’re just waiting for the tick counter (which is updated by the ISR) to reach the delay value we’ve entered. The tick counter keeps incrementing as the ISR is called multiple times per second, allowing us to accurately manage delays.
In short: The SysTick timer and ISR are hardware-driven and operate in the background, regardless of what the main program is doing. Understanding this concept is key to managing time-sensitive tasks in embedded systems! 🚀
#EmbeddedSystems #SysTick #ISR #ClockCycles #Microcontrollers #RealTimeSystems #EmbeddedProgramming #Timers #Interrupts #Engineering
