Files
Shmingo-HAL/SHAL/Src/STM32L4XX/Core/SHAL_CORE.cpp
2025-10-08 23:37:10 -07:00

43 lines
1017 B
C++

//
// Created by Luca on 9/15/2025.
//
#include "SHAL_CORE.h"
void SHAL_init(){
systick_init(); //Just this for now
}
void systick_init(){
SysTick->CTRL = 0; //Disable first
SysTick->LOAD = 0xFFFFFF; //Max 24-bit
SysTick->VAL = 0; //Clear
SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk | SysTick_CTRL_ENABLE_Msk;
}
void SHAL_delay_us(uint32_t us){
uint32_t ticks = us * (SystemCoreClock / 1000000U);
uint32_t start = SysTick->VAL;
//Calculate target value (may wrap around)
uint32_t target = (start >= ticks) ? (start - ticks) : (start + 0x01000000 - ticks);
target &= 0x00FFFFFF;
//Wait until we reach the target
if (start >= ticks) {
//No wraparound case
while (SysTick->VAL > target) {}
} else {
while (SysTick->VAL <= start) {} //Wait for wraparound
while (SysTick->VAL > target) {} //Wait for target
}
}
void SHAL_delay_ms(uint32_t ms){
while(ms-- > 0){
SHAL_delay_us(1000);
}
}