38 lines
1.1 KiB
C
38 lines
1.1 KiB
C
#include "systick.h"
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#include "ch32v003fun.h"
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#include "debug.h"
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// ms counter
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volatile uint32_t systick_millis = 0;
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void init_systick(void) {
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SysTick->CTLR = 0;
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SysTick->CMP = SYSTICK_ONE_MILLISECOND - 1;
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SysTick->CNT = 0;
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systick_millis = 0;
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// Enable the SysTick IRQ
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NVIC_SetPriority(SysTicK_IRQn, 0xf0);
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NVIC_EnableIRQ(SysTicK_IRQn);
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/* Enable SysTick counter, IRQ, HCLK/1 */
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SysTick->CTLR = SYSTICK_CTLR_STE | SYSTICK_CTLR_STIE | SYSTICK_CTLR_STCLK;
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}
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/*
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* SysTick ISR - must be lightweight to prevent the CPU from bogging down.
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* Increments Compare Register and systick_millis when triggered (every 1ms)
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* NOTE: the `__attribute__((interrupt))` attribute is very important
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*/
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void SysTick_Handler(void) __attribute__((interrupt));
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void SysTick_Handler(void) {
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// Increment the Compare Register for the next trigger
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// If more than this number of ticks elapse before the trigger is reset,
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// you may miss your next interrupt trigger
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// (Make sure the IQR is lightweight and CMP value is reasonable)
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SysTick->CMP += SYSTICK_ONE_MILLISECOND;
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// clear irq
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SysTick->SR = 0;
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systick_millis++;
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} |