diff options
Diffstat (limited to 'stm/rtc.c')
| -rw-r--r-- | stm/rtc.c | 30 |
1 files changed, 21 insertions, 9 deletions
@@ -8,8 +8,20 @@ #include "rtc.h" void rtc_init(void) { - uint32_t rtc_clksrc; - uint32_t timeout = 1000000; + /* Enable the PWR clock */ + RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR, ENABLE); + + /* Allow access to RTC */ + PWR_BackupAccessCmd(ENABLE); + + if (RTC_ReadBackupRegister(RTC_BKP_DR0) == 0x32F2) { + // RTC still alive, so don't re-init it + // wait for RTC APB register synchronisation + RTC_WaitForSynchro(); + return; + } + + uint32_t timeout = 10000000; /* Enable the PWR clock */ RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR, ENABLE); @@ -26,7 +38,10 @@ void rtc_init(void) { /* If LSE timed out, use LSI instead */ if (timeout == 0) { - /* Enable the LSI OSC */ + // Disable the LSE OSC + RCC_LSEConfig(RCC_LSE_OFF); + + // Enable the LSI OSC RCC_LSICmd(ENABLE); /* Wait till LSI is ready */ @@ -34,15 +49,12 @@ void rtc_init(void) { } /* Use LSI as the RTC Clock Source */ - rtc_clksrc = RCC_RTCCLKSource_LSI; + RCC_RTCCLKConfig(RCC_RTCCLKSource_LSI); } else { /* Use LSE as the RTC Clock Source */ - rtc_clksrc = RCC_RTCCLKSource_LSE; + RCC_RTCCLKConfig(RCC_RTCCLKSource_LSE); } - /* Select the RTC Clock Source */ - RCC_RTCCLKConfig(rtc_clksrc); - /* Note: LSI is around (32KHz), these dividers should work either way */ /* ck_spre(1Hz) = RTCCLK(LSE) /(uwAsynchPrediv + 1)*(uwSynchPrediv + 1)*/ uint32_t uwSynchPrediv = 0xFF; @@ -78,7 +90,7 @@ void rtc_init(void) { RTC_SetTime(RTC_Format_BCD, &RTC_TimeStructure); // Indicator for the RTC configuration - //RTC_WriteBackupRegister(RTC_BKP_DR0, 0x32F2); + RTC_WriteBackupRegister(RTC_BKP_DR0, 0x32F2); } /******************************************************************************/ |