#include "main.h"
#include "bsp_pin.h"

void bsp_pin_init(GPIO_TypeDef *port, uint16_t pin, uint8_t mode)
{
    GPIO_InitTypeDef GPIO_InitStruct = {0};
    GPIO_InitStruct.Pin = pin;
    GPIO_InitStruct.Mode = (mode == 0) ? GPIO_MODE_OUTPUT_PP : GPIO_MODE_INPUT;
	
	if (mode == 1) GPIO_InitStruct.Pull = GPIO_PULLUP;
    else if (mode == 2) GPIO_InitStruct.Pull = GPIO_PULLDOWN;
	else GPIO_InitStruct.Pull = GPIO_NOPULL;
		
	if (mode == 0) GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
    HAL_GPIO_Init(port, &GPIO_InitStruct);
}

void delay_us(int nus)
{		
	uint32_t ticks;
	uint32_t told,tnow,tcnt=0;
	uint32_t reload=SysTick->LOAD;				//LOAD的值	    	 
	ticks=nus*72; 						//需要的节拍数 
	told=SysTick->VAL;        				//刚进入时的计数器值
	while(1)
	{
		tnow=SysTick->VAL;	
		if(tnow!=told)
		{	    
			if(tnow<told)tcnt+=told-tnow;	//这里注意一下SYSTICK是一个递减的计数器就可以了.
			else tcnt+=reload-tnow+told;	    
			told=tnow;
			if(tcnt>=ticks)break;			//时间超过/等于要延迟的时间,则退出.
		}  
	};
}