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Color Oled(SSD1331) connect to STMicroelectronics Nucleo-F466
Diff: mbed-os/targets/TARGET_NUVOTON/TARGET_M451/rtc_api.c
- Revision:
- 0:8fdf9a60065b
diff -r 000000000000 -r 8fdf9a60065b mbed-os/targets/TARGET_NUVOTON/TARGET_M451/rtc_api.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed-os/targets/TARGET_NUVOTON/TARGET_M451/rtc_api.c Wed Oct 10 00:33:53 2018 +0000 @@ -0,0 +1,213 @@ +/* mbed Microcontroller Library + * Copyright (c) 2015-2016 Nuvoton + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "rtc_api.h" + +#if DEVICE_RTC + +#include "mbed_wait_api.h" +#include "mbed_error.h" +#include "nu_modutil.h" +#include "nu_miscutil.h" +#include "mbed_mktime.h" + +/* Micro seconds per second */ +#define NU_US_PER_SEC 1000000 +/* Timer clock per second + * + * NOTE: This dependents on real hardware. + */ +#define NU_RTCCLK_PER_SEC ((CLK->CLKSEL3 & CLK_CLKSEL3_SC0SEL_Msk) ? __LIRC : __LXT) + +/* Strategy for implementation of RTC HAL + * + * H/W RTC just supports year range 2000~2099, which cannot fully cover POSIX time (starting since 2970) + * and date time of struct TM (starting since 1900). + * + * To conquer the difficulty, we don't use H/W RTC to keep real date time. Instead, we use it to keep + * elapsed time in seconds since one reference time point. The strategy would be: + * + * 1. Choose DATETIME_HWRTC_ORIGIN (00:00:00 UTC, Saturday, 1 January 2000) as reference time point of H/W RTC. + * 2. t_hwrtc_origin = DATETIME_HWRTC_ORIGIN in POSIX time + * 3. t_hwrtc_elapsed = t_hwrtc_origin + elapsed time since t_hwrtc_origin + * 4. t_write = POSIX time set by rtc_write(). + * 5. t_present = rtc_read() = t_write + (t_hwrtc_elapsed - t_hwrtc_origin) + * + * 1900 + * |---------------------------------------------------------------------------------| + * 1970 t_write t_present + * |---------|-------|-----------------|---------------------------------------------| + * + * 2000 + * |-----------------|---------------------------------------------------------------| + * t_hwrtc_origin t_hwrtc_elapsed + * + */ +/* Start year of struct TM*/ +#define NU_TM_YEAR0 1900 +/* Start year of POSIX time (set_time()/time()) */ +#define NU_POSIX_YEAR0 1970 +/* Start year of H/W RTC */ +#define NU_HWRTC_YEAR0 2000 + +/* RTC H/W origin time: 00:00:00 UTC, Saturday, 1 January 2000 */ +static const S_RTC_TIME_DATA_T DATETIME_HWRTC_ORIGIN = { + 2000, /* Year value, range between 2000 ~ 2099 */ + 1, /* Month value, range between 1 ~ 12 */ + 1, /* Day value, range between 1 ~ 31 */ + RTC_SATURDAY, /* Day of the week */ + 0, /* Hour value, range between 0 ~ 23 */ + 0, /* Minute value, range between 0 ~ 59 */ + 0, /* Second value, range between 0 ~ 59 */ + RTC_CLOCK_24, /* 12-Hour (RTC_CLOCK_12) / 24-Hour (RTC_CLOCK_24) */ + 0 /* RTC_AM / RTC_PM (used only for 12-Hour) */ +}; +/* t_hwrtc_origin initialized or not? */ +static bool t_hwrtc_origin_inited = 0; +/* POSIX time of DATETIME_HWRTC_ORIGIN (since 00:00:00 UTC, Thursday, 1 January 1970) */ +static time_t t_hwrtc_origin = 0; +/* POSIX time set by rtc_write() */ +static time_t t_write = 0; +/* Convert date time from H/W RTC to struct TM */ +static void rtc_convert_datetime_hwrtc_to_tm(struct tm *datetime_tm, const S_RTC_TIME_DATA_T *datetime_hwrtc); + +static const struct nu_modinit_s rtc_modinit = {RTC_0, RTC_MODULE, 0, 0, 0, RTC_IRQn, NULL}; + +void rtc_init(void) +{ + if (rtc_isenabled()) { + return; + } + + RTC_Open(NULL); + + /* POSIX time origin (00:00:00 UTC, Thursday, 1 January 1970) */ + rtc_write(0); +} + +void rtc_free(void) +{ + CLK_DisableModuleClock(rtc_modinit.clkidx); +} + +int rtc_isenabled(void) +{ + // NOTE: To access (RTC) registers, clock must be enabled first. + if (! (CLK->APBCLK0 & CLK_APBCLK0_RTCCKEN_Msk)) { + // Enable IP clock + CLK_EnableModuleClock(rtc_modinit.clkidx); + } + + // NOTE: Check RTC Init Active flag to support crossing reset cycle. + return !! (RTC->INIT & RTC_INIT_ACTIVE_Msk); +} + +time_t rtc_read(void) +{ + /* NOTE: After boot, RTC time registers are not synced immediately, about 1 sec latency. + * RTC time got (through RTC_GetDateAndTime()) in this sec would be last-synced and incorrect. + */ + if (! rtc_isenabled()) { + rtc_init(); + } + + /* Used for intermediary between date time of H/W RTC and POSIX time */ + struct tm datetime_tm; + + if (! t_hwrtc_origin_inited) { + t_hwrtc_origin_inited = 1; + + /* Convert date time from H/W RTC to struct TM */ + rtc_convert_datetime_hwrtc_to_tm(&datetime_tm, &DATETIME_HWRTC_ORIGIN); + /* Convert date time of struct TM to POSIX time */ + if (! _rtc_maketime(&datetime_tm, &t_hwrtc_origin, RTC_FULL_LEAP_YEAR_SUPPORT)) { + return 0; + } + + /* Load t_write from RTC spare register to cross reset cycle */ + RTC_WaitAccessEnable(); + RTC_EnableSpareAccess(); + RTC_WaitAccessEnable(); + t_write = RTC_READ_SPARE_REGISTER(0); + RTC_WaitAccessEnable(); + while (! (RTC->SPRCTL & RTC_SPRCTL_SPRRWRDY_Msk)); + } + + S_RTC_TIME_DATA_T hwrtc_datetime_2K_present; + RTC_WaitAccessEnable(); + RTC_GetDateAndTime(&hwrtc_datetime_2K_present); + /* Convert date time from H/W RTC to struct TM */ + rtc_convert_datetime_hwrtc_to_tm(&datetime_tm, &hwrtc_datetime_2K_present); + /* Convert date time of struct TM to POSIX time */ + time_t t_hwrtc_elapsed; + if (! _rtc_maketime(&datetime_tm, &t_hwrtc_elapsed, RTC_FULL_LEAP_YEAR_SUPPORT)) { + return 0; + } + + /* Present time in POSIX time */ + time_t t_present = t_write + (t_hwrtc_elapsed - t_hwrtc_origin); + return t_present; +} + +void rtc_write(time_t t) +{ + if (! rtc_isenabled()) { + rtc_init(); + } + + t_write = t; + + /* Store t_write to RTC spare register to cross reset cycle */ + RTC_WaitAccessEnable(); + RTC_EnableSpareAccess(); + RTC_WaitAccessEnable(); + RTC_WRITE_SPARE_REGISTER(0, t_write); + RTC_WaitAccessEnable(); + while (! (RTC->SPRCTL & RTC_SPRCTL_SPRRWRDY_Msk)); + + RTC_WaitAccessEnable(); + RTC_SetDateAndTime((S_RTC_TIME_DATA_T *) &DATETIME_HWRTC_ORIGIN); + /* NOTE: When engine is clocked by low power clock source (LXT/LIRC), we need to wait for 3 engine clocks. */ + wait_us((NU_US_PER_SEC / NU_RTCCLK_PER_SEC) * 3); +} + +/* + struct tm + tm_sec seconds after the minute 0-61 + tm_min minutes after the hour 0-59 + tm_hour hours since midnight 0-23 + tm_mday day of the month 1-31 + tm_mon months since January 0-11 + tm_year years since 1900 + tm_wday days since Sunday 0-6 + tm_yday days since January 1 0-365 + tm_isdst Daylight Saving Time flag +*/ +static void rtc_convert_datetime_hwrtc_to_tm(struct tm *datetime_tm, const S_RTC_TIME_DATA_T *datetime_hwrtc) +{ + datetime_tm->tm_year = datetime_hwrtc->u32Year - NU_TM_YEAR0; + datetime_tm->tm_mon = datetime_hwrtc->u32Month - 1; + datetime_tm->tm_mday = datetime_hwrtc->u32Day; + datetime_tm->tm_wday = datetime_hwrtc->u32DayOfWeek; + datetime_tm->tm_hour = datetime_hwrtc->u32Hour; + if (datetime_hwrtc->u32TimeScale == RTC_CLOCK_12 && datetime_hwrtc->u32AmPm == RTC_PM) { + datetime_tm->tm_hour += 12; + } + datetime_tm->tm_min = datetime_hwrtc->u32Minute; + datetime_tm->tm_sec = datetime_hwrtc->u32Second; +} + +#endif