rt-thread/bsp/n32g452xx/Libraries/rt_drivers/drv_common.c

66 lines
1.3 KiB
C

/*
* Copyright (c) 2006-2021, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2021-08-20 breo.com first version
*/
#include "drv_common.h"
#include "board.h"
#ifdef RT_USING_SERIAL
#ifdef RT_USING_SERIAL_V2
#include "drv_usart_v2.h"
#else
#include "drv_usart.h"
#endif
#endif
#ifdef RT_USING_FINSH
#include <finsh.h>
static void reboot(uint8_t argc, char **argv)
{
rt_hw_cpu_reset();
}
MSH_CMD_EXPORT(reboot, Reboot System);
#endif /* RT_USING_FINSH */
/**
* This function will delay for some us.
*
* @param us the delay time of us
*/
void rt_hw_us_delay(rt_uint32_t us)
{
rt_uint32_t ticks;
rt_uint32_t told, tnow, tcnt = 0;
rt_uint32_t reload = SysTick->LOAD;
ticks = us * reload / (1000000 / RT_TICK_PER_SECOND);
told = SysTick->VAL;
while (1)
{
tnow = SysTick->VAL;
if (tnow != told)
{
if (tnow < told)
{
tcnt += told - tnow;
}
else
{
tcnt += reload - tnow + told;
}
told = tnow;
if (tcnt >= ticks)
{
break;
}
}
}
}