RTC的使用
1、GD32内部集成RTC模块，在使用备用电源的情况下，配置备份域功能，可以做到待机数据不丢失功能，以及RTC待机唤醒功能。但我手头开发版并没有引出VBAT管脚，所以这里只演示RTC的基本功能，设置时间，显示时间等。
代码来自于官方RTC的demo
2、Common目录下新建rtc目录，将官方demo中的rtc.c rtc.h copy到相应目录。
rtc.c
/*!
\file rtc.c
\brief RTC check and config,time_show and time_adjust function
\version 2014-12-26, V1.0.0, firmware for GD32F10x
\version 2017-06-20, V2.0.0, firmware for GD32F10x
\version 2018-07-31, V2.1.0, firmware for GD32F10x
\version 2020-09-30, V2.2.0, firmware for GD32F10x
*/
/*
Copyright (c) 2020, GigaDevice Semiconductor Inc.
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
3. Neither the name of the copyright holder nor the names of its contributors
may be used to endorse or promote products derived from this software without
specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
OF SUCH DAMAGE.
*/
#include "rtc.h"
/* enter the second interruption,set the second interrupt flag to 1 */
__IO uint32_t timedisplay;
/*!
\brief configure the nested vectored interrupt controller
\param[in] none
\param[out] none
\retval none
*/
void nvic_configuration(void)
{
nvic_priority_group_set(NVIC_PRIGROUP_PRE1_SUB3);
nvic_irq_enable(RTC_IRQn,1,0);
}
/*!
\brief configure the RTC
\param[in] none
\param[out] none
\retval none
*/
void rtc_configuration(void)
{
/* enable PMU and BKPI clocks */
rcu_periph_clock_enable(RCU_BKPI);
rcu_periph_clock_enable(RCU_PMU);
/* allow access to BKP domain */
pmu_backup_write_enable();
/* reset backup domain */
bkp_deinit();
/* enable LXTAL */
rcu_osci_on(RCU_LXTAL);
/* wait till LXTAL is ready */
rcu_osci_stab_wait(RCU_LXTAL);
/* select RCU_LXTAL as RTC clock source */
rcu_rtc_clock_config(RCU_RTCSRC_LXTAL);
/* enable RTC Clock */
rcu_periph_clock_enable(RCU_RTC);
/* wait for RTC registers synchronization */
rtc_register_sync_wait();
/* wait until last write operation on RTC registers has finished */
rtc_lwoff_wait();
/* enable the RTC second interrupt*/
rtc_interrupt_enable(RTC_INT_SECOND);
/* wait until last write operation on RTC registers has finished */
rtc_lwoff_wait();
/* set RTC prescaler: set RTC period to 1s */
rtc_prescaler_set(32767);
/* wait until last write operation on RTC registers has finished */
rtc_lwoff_wait();
}
/*!
\brief return the time entered by user, using Hyperterminal
\param[in] none
\param[out] none
\retval current time of RTC counter value
*/
uint32_t time_regulate(void)
{
uint32_t tmp_hh = 0xFF, tmp_mm = 0xFF, tmp_ss = 0xFF;
printf("\r\n==============Time Settings=====================================");
printf("\r\n Please Set Hours");
while (tmp_hh == 0xFF){
tmp_hh = usart_scanf(23);
}
printf(": %d", tmp_hh);
printf("\r\n Please Set Minutes");
while (tmp_mm == 0xFF){
tmp_mm = usart_scanf(59);
}
printf(": %d", tmp_mm);
printf("\r\n Please Set Seconds");
while (tmp_ss == 0xFF){
tmp_ss = usart_scanf(59);
}
printf(": %d", tmp_ss);
/* return the value store in RTC counter register */
return((tmp_hh*3600 + tmp_mm*60 + tmp_ss));
}
/*!
\brief adjust time
\param[in] none
\param[out] none
\retval none
*/
void time_adjust(void)
{
/* wait until last write operation on RTC registers has finished */
rtc_lwoff_wait();
/* change the current time */
rtc_counter_set(time_regulate());
/* wait until last write operation on RTC registers has finished */
rtc_lwoff_wait();
}
/*!
\brief display the current time
\param[in] timeVar: RTC counter value
\param[out] none
\retval none
*/
void time_display(uint32_t timevar)
{
uint32_t thh = 0, tmm = 0, tss = 0;
/* compute hours */
thh = timevar / 3600;
/* compute minutes */
tmm = (timevar % 3600) / 60;
/* compute seconds */
tss = (timevar % 3600) % 60;
printf(" Time: %0.2d:%0.2d:%0.2d\r\n", thh, tmm, tss);
}
/*!
\brief show the current time (HH:MM:SS) on the Hyperterminal
\param[in] none
\param[out] none
\retval none
*/
void time_show(void)
{
printf("\n\r");
/* infinite loop */
while (1){
/* if 1s has paased */
if (timedisplay == 1){
/* display current time */
time_display(rtc_counter_get());
timedisplay = 0;
}
}
}
/*!
\brief get numeric values from the hyperterminal
\param[in] value: input value from the hyperterminal
\param[out] none
\retval input value in BCD mode
*/
uint8_t usart_scanf(uint32_t value)
{
uint32_t index = 0;
uint32_t tmp[2] = {0, 0};
while (index < 2){
/* loop until RBNE = 1 */
while (usart_flag_get(USART0, USART_FLAG_RBNE) == RESET);
tmp[index++] = (usart_data_receive(USART0));
if ((tmp[index - 1] < 0x30) || (tmp[index - 1] > 0x39)){
printf("\n\rPlease enter valid number between 0 and 9\n");
index--;
}
}
/* calculate the Corresponding value */
index = (tmp[1] - 0x30) + ((tmp[0] - 0x30) * 10);
/* check */
if (index > value){
printf("\n\rPlease enter valid number between 0 and %d\n", value);
return 0xFF;
}
return index;
}
// golbal function
void rtc_config(void)
{
nvic_configuration();//中断配置
rtc_configuration();//RTC配置
rcu_periph_clock_enable(RCU_PMU);//电源管理使能
pmu_backup_write_enable();//backup写使能
/* wait for RTC registers synchronization */
rtc_register_sync_wait();
/* enable the RTC second */
rtc_interrupt_enable(RTC_INT_SECOND);
/* wait until last write operation on RTC registers has finished */
rtc_lwoff_wait();
}
rtc.h
/*!
\file rtc.h
\brief headfile of RTC check and config,time_show and time_adjust function
\version 2014-12-26, V1.0.0, firmware for GD32F10x
\version 2017-06-20, V2.0.0, firmware for GD32F10x
\version 2018-07-31, V2.1.0, firmware for GD32F10x
*/
/*
Copyright (c) 2018, GigaDevice Semiconductor Inc.
All rights reserved.
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
3. Neither the name of the copyright holder nor the names of its contributors
may be used to endorse or promote products derived from this software without
specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
OF SUCH DAMAGE.
*/
#ifndef __RTC_H
#define __RTC_H
#include "gd32f30x.h"
#include <stdio.h>
void nvic_configuration(void);
void rtc_configuration(void);
uint32_t time_regulate(void);
void time_adjust(void);
void time_display(uint32_t timevar);
void time_show(void);
uint8_t usart_scanf(uint32_t value);
void rtc_config(void);
#endif /* __RTC_H */
3、gd32f30x_it.c中添加回调函数
#ifdef ENABLE_RTC_TEST
extern uint32_t timedisplay;
void RTC_IRQHandler(void)
{
if (rtc_flag_get(RTC_FLAG_SECOND) != RESET){
/* clear the RTC second interrupt flag*/
rtc_flag_clear(RTC_FLAG_SECOND);
/* enable time update */
timedisplay = 1;
/* wait until last write operation on RTC registers has finished */
rtc_lwoff_wait();
/* reset RTC counter when time is 23:59:59 */
if (rtc_counter_get() == 0x00015180){
rtc_counter_set(0x0);
/* wait until last write operation on RTC registers has finished */
rtc_lwoff_wait();
}
}
}
#endif
4、main.c调用：
5、开机后，首先设置时间，然后每秒打印一次时间。
6、另外，Makefile中增加了对rtc功能的编译选项，如果ENABLE_RTC_TEST = no的话，将不编译rtc相关代码。
7、代码路径：https://gitee.com/xiaoguo-tec_0/gd32-iap-code.git