diff options
| -rw-r--r-- | bsp/stm32/libraries/HAL_Drivers/drv_common.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/bsp/stm32/libraries/HAL_Drivers/drv_common.c b/bsp/stm32/libraries/HAL_Drivers/drv_common.c index e267b94b24..350c3fab40 100644 --- a/bsp/stm32/libraries/HAL_Drivers/drv_common.c +++ b/bsp/stm32/libraries/HAL_Drivers/drv_common.c @@ -87,6 +87,41 @@ void _Error_Handler(char *s, int num) } /** + * 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; + } + } + } +} + +/** * This function will initial STM32 board. */ RT_WEAK void rt_hw_board_init() |