tags: [entity]
type: entity
topic: stm32-lower
note: 19
created: 2026-07-16
updated: 2026-07-16
Note 19: BKP/RTC (lower/stm32/21~26)
Projects
| # |
Directory |
Topic |
Library |
| 21 |
21_bkp_test_register |
BKP backup registers |
Register |
| 22 |
22_bkp_test_hal |
BKP backup registers |
HAL |
| 23 |
23_rtc_alarm_standby_register |
RTC alarm + standby wake |
Register |
| 24 |
24_rtc_alarm_standby_hal |
RTC alarm + standby wake |
HAL |
| 25 |
25_rtc_calendar_register |
RTC calendar |
Register |
| 26 |
26_rtc_calendar_hal |
RTC calendar |
HAL |
Code Accuracy Audit
Path Audit
| Claimed Path |
Actual Path |
Status |
stm32/21_bkp_test_register/Hardware/BKP/bkp.c |
21_bkp_test_register/Hardware/BKP/bkp.c |
✅ Correct |
stm32/25_rtc_calendar_register/Hardware/RTC/rtc.c |
25_rtc_calendar_register/Hardware/RTC/rtc.c |
✅ Correct |
stm32/25_rtc_calendar_register/Hardware/RTC/rtc.h |
25_rtc_calendar_register/Hardware/RTC/rtc.h |
✅ Correct |
stm32/25_rtc_calendar_register/User/main.c |
25_rtc_calendar_register/User/main.c |
✅ Correct |
stm32/23_rtc_alarm_standby_register/User/main.c |
23_rtc_alarm_standby_register/User/main.c |
✅ Correct |
BKP Code (bkp.c)
| Claimed by Note |
Actual Code |
Match? |
| `RCC->APB1ENR |
= RCC_APB1ENR_PWREN` |
Present |
| `PWR->CR |
= PWR_CR_DBP` |
Present |
| `RCC->APB1ENR |
= RCC_APB1ENR_BKPEN` |
Present |
bkp.h has #include "stm32f10x.h", BKP_Init(void) |
Present |
✅ Match |
RTC Init (25_rtc_calendar_register/Hardware/RTC/rtc.c)
| Claimed by Note |
Actual Code (lines) |
Match? |
| `RCC->APB1ENR |
= RCC_APB1ENR_PWREN` |
Line 15 |
| `PWR->CR |
= PWR_CR_DBP` |
Line 18 |
| `RCC->BDCR |
= RCC_BDCR_RTCEN` |
Line 28 |
| `RCC->BDCR |
= RCC_BDCR_LSEON` |
Line 31 |
while (!(RCC->BDCR & RCC_BDCR_LSERDY)) |
Lines 32-34 |
✅ Match |
| `RCC->BDCR &= ~RCC_BDCR_RTCSEL; RCC->BDCR |
= RCC_BDCR_RTCSEL_0` |
Lines 37-38 |
Wait RTC_CRL_RTOFF |
Lines 42-44 |
✅ Match |
| `RTC->CRL |
= RTC_CRL_CNF` |
Line 47 |
RTC->PRLH = 0; RTC->PRLL = 0x7fff |
Lines 50-51 |
✅ Match |
RTC->CRL &= ~RTC_CRL_CNF |
Line 54 |
✅ Match |
RTC_SetAlarm
| Claimed by Note |
Actual Code |
Match? |
RTC->CRL &= ~RTC_CRL_ALRF |
Line 66 |
✅ Match |
| Wait RTOFF |
Line 69 |
✅ Match |
| `RTC->CRL |
= RTC_CRL_CNF` |
Line 74 |
RTC->CNTH = 0; RTC->CNTL = 0 |
Lines 78-79 |
✅ Match |
s -= 1; RTC->ALRH = (s >> 16) & 0xffff; RTC->ALRL = (s >> 0) & 0xffff |
Lines 82-84 |
✅ Match |
RTC->CRL &= ~RTC_CRL_CNF |
Line 87 |
✅ Match |
RTC_SetTimestamp
| Claimed by Note |
Actual Code |
Match? |
| Wait RTOFF, CNF=1, set CNTH/CNTL, CNF=0, wait RTOFF |
Lines 99-116 |
✅ Match |
RTC_GetDateTime
| Claimed by Note |
Actual Code |
Match? |
while (!(RTC->CRL & RTC_CRL_RSF)) |
Line 123 |
✅ Match |
| `uint32_t second = RTC->CNTH << 16 |
RTC->CNTL` |
Line 127 |
struct tm* ptm = localtime(&second) |
Line 130 |
✅ Match |
dateTime->year = ptm->tm_year + 1900 etc. |
Lines 133-138 |
✅ Match |
DateTime struct (rtc.h)
| Claimed by Note |
Actual Code |
Match? |
typedef struct { uint16_t year; uint8_t month; ... } DateTime; |
Present |
✅ Match |
Function prototypes: RTC_Init, RTC_SetAlarm, RTC_SetTimestamp, RTC_GetDateTime |
Present |
✅ Match |
RTC Alarm + Standby (23_rtc_alarm_standby_register)
Note claims loop: RTC_SetAlarm(5); enter_standby_mode(); with PA0 wakeup → matches actual code.
HAL RTC Calendar
Note's HAL code (RTC_TimeTypeDef, RTC_DateTypeDef, HAL_RTC_SetTime, HAL_RTC_GetTime) matches project 26.
BKP Store Date (HAL)
Note's read_stored_date / write_stored_date functions using HAL_RTCEx_BKUPRead/Write — these exist in project 22's code.
Summary
Overall Accuracy: Excellent (99%+)
Issues Found: None significant. RTC register operations, HAL API usage, BKP operations all match actual source files exactly. This is the most technically accurate section.
