Differences

This shows you the differences between two versions of the page.

--- stm32:peripherals:systick [2016/03/04 13:39] – feur
+++ stm32:peripherals:systick [2022/12/27 17:53] (current) – [VAL] ruan
@@ Line 1: / Line 1: @@
 ====== System Tick Timer ======
+The STM32F429ZI offers a 24 bit system tick timer. It is a simple down counter. \\
+The system tick timer counts down from the reload value to zero and generates an interrupt. \\
 \\ {{systick_complete.svg}} \\ \\
@@ Line 5: / Line 8: @@
 ===== Registers =====
-==== CTRL ====
+==== CTRL - Control and status register ====
-Control and status register
 \\ {{systick_reg_ctrl.svg}} \\ \\
@@ Line 16: / Line 17: @@
 |TICKINT|0|Systick interrupt disabled (reset state)|
 |:::|1|Systick interrupt enabled|
-|CLKSRC|0|Systick clock ==> f<sub>HCLK</sub> / 8 (reset state)|
+|CLKSRC|0|Systick clock => f<sub>HCLK</sub> / 8 (reset state)|
-|:::|1|Systick clock ==> f<sub>HCLK</sub>|
+|:::|1|Systick clock => f<sub>HCLK</sub>|
-==== LOAD ====
+==== LOAD - Reload value register ====
-Reload value register
 \\ {{systick_reg_load.svg}} \\ \\
@@ Line 27: / Line 26: @@
 * Reload value of SysTick timer.
-==== VAL ====
+==== VAL - Current value register ====
-Current value register
 \\ {{systick_reg_val.svg}} \\ \\
 * Current value of SysTick timer.
+===== Programming Example =====
+<code c>
+#include "reg_stm32f4xx.h"
+STK->CTRL = (0x3 << 1u);             /* Set clock and interrupt. */
+STK->LOAD = 84000u;                  /* Set reload value: 84 MHz / 84000 -> 1 ms. */
+STK->CTRL |= (0x1 << 0u);            /* Enable timer. */
+void SysTick_Handler(void)
+{
+    /* Handler for SysTick interrupt. */
+}
+</code>
+\\