M41T62 is a serial real-time clock (RTC) made by STMicroelectronics.
Dependents: LPC1114_data_logger Check_external_RTC LPC1114_barometer_with_data_logging
m41t62_rtc.cpp
- Committer:
- kenjiArai
- Date:
- 2017-08-23
- Revision:
- 4:0c07690cb24f
- Parent:
- 3:41c351da2fdf
- Child:
- 5:959683e91979
File content as of revision 4:0c07690cb24f:
/* * mbed library program * Control M41T62 RTC Module * * Copyright (c) 2014,'15,'17 Kenji Arai / JH1PJL * http://www.page.sannet.ne.jp/kenjia/index.html * http://mbed.org/users/kenjiArai/ * Created: June 21st, 2014 * Revised: August 23rd, 2017 */ /* *---------------- REFERENCE ---------------------------------------------------------------------- * http://www.st-japan.co.jp/web/jp/catalog/sense_power/FM151/CL1410/SC403/PF82507 * http://strawberry-linux.com/catalog/items?code=12062 */ #include "mbed.h" #include "m41t62_rtc.h" M41T62::M41T62 (PinName p_sda, PinName p_scl) : _i2c_p(new I2C(p_sda, p_scl)), _i2c(*_i2c_p) { M41T62_addr = M41T62ADDR; _i2c.frequency(100000); } M41T62::M41T62 (I2C& p_i2c) : _i2c(p_i2c) { M41T62_addr = M41T62ADDR; _i2c.frequency(100000); } void M41T62::read_rtc_std (tm *t) { rtc_time time; read_rtc_direct(&time); t->tm_sec = time.rtc_seconds; t->tm_min = time.rtc_minutes; t->tm_hour = time.rtc_hours; t->tm_mday = time.rtc_date; if ( time.rtc_weekday == RTC_Wk_Sunday) { t->tm_wday = 0; // Sun is not 7 but 0 } else { t->tm_wday = time.rtc_weekday; } t->tm_mon = time.rtc_month - 1; t->tm_year = time.rtc_year_raw + 100; t->tm_isdst= 0; } void M41T62::write_rtc_std (tm *t) { rtc_time time; time.rtc_seconds = t->tm_sec; time.rtc_minutes = t->tm_min; time.rtc_hours = t->tm_hour; time.rtc_date = t->tm_mday; if ( t->tm_wday == 0) { time.rtc_weekday = RTC_Wk_Sunday; } else { time.rtc_weekday = t->tm_wday; } time.rtc_month = t->tm_mon + 1; time.rtc_year_raw = t->tm_year - 100; write_rtc_direct(&time); } void M41T62::read_rtc_direct (rtc_time *tm) { uint8_t eep_dt; eep_dt = M41T62_REG_SSEC; _i2c.write((int)M41T62_addr, (char *)eep_dt, 1); _i2c.read((int)M41T62_addr, (char *)rtc_buf, 8); tm->rtc_seconds = bcd2bin(rtc_buf[M41T62_REG_SEC] & 0x7f); tm->rtc_minutes = bcd2bin(rtc_buf[M41T62_REG_MIN] & 0x7f); tm->rtc_hours = bcd2bin(rtc_buf[M41T62_REG_HOUR] & 0x3f); tm->rtc_date = bcd2bin(rtc_buf[M41T62_REG_DAY] & 0x3f); tm->rtc_weekday = rtc_buf[M41T62_REG_WDAY] & 0x07; tm->rtc_month = bcd2bin(rtc_buf[M41T62_REG_MON] & 0x1f); tm->rtc_year_raw= bcd2bin(rtc_buf[M41T62_REG_YEAR]); tm->rtc_year = tm->rtc_year_raw + 100 + 1900; } void M41T62::write_rtc_direct (rtc_time *tm) { uint8_t eep_dt; eep_dt = M41T62_REG_SSEC; _i2c.write((int)M41T62_addr, (char *)eep_dt, 1); _i2c.read((int)M41T62_addr, (char *)rtc_buf, 8); rtc_buf[0] = M41T62_REG_SSEC; rtc_buf[M41T62_REG_SSEC + 1] = 0; rtc_buf[M41T62_REG_YEAR + 1] = bin2bcd(tm->rtc_year_raw); rtc_buf[M41T62_REG_MON + 1] = bin2bcd(tm->rtc_month) | (rtc_buf[M41T62_REG_MON] & ~0x1f); rtc_buf[M41T62_REG_DAY + 1] = bin2bcd(tm->rtc_date) | (rtc_buf[M41T62_REG_DAY] & ~0x3f); rtc_buf[M41T62_REG_WDAY + 1] = (tm->rtc_weekday & 0x07) | (rtc_buf[M41T62_REG_WDAY] & ~0x07); rtc_buf[M41T62_REG_HOUR + 1] = bin2bcd(tm->rtc_hours) | (rtc_buf[M41T62_REG_HOUR] & ~0x3f); rtc_buf[M41T62_REG_MIN + 1] = bin2bcd(tm->rtc_minutes) | (rtc_buf[M41T62_REG_MIN] & ~0x7f); rtc_buf[M41T62_REG_SEC + 1] = bin2bcd(tm->rtc_seconds) | (rtc_buf[M41T62_REG_SEC] & ~0x7f); _i2c.write((int)M41T62_addr, (char *)rtc_buf, 9); } void M41T62::frequency(int hz) { _i2c.frequency(hz); } void M41T62::set_sq_wave (uint8_t sqw_dt) { uint8_t eep_dt[2]; // set SQW frequency eep_dt[0] = M41T62_REG_WDAY; _i2c.write((int)M41T62_addr, (char *)eep_dt, 1); _i2c.read((int)M41T62_addr, (char *)eep_dt, 1); eep_dt[1] = (eep_dt[0] & 0x07) | (sqw_dt << 4); eep_dt[0] = M41T62_REG_WDAY; _i2c.write((int)M41T62_addr, (char *)rtc_buf, 2); // set or clear SQWE eep_dt[0] = M41T62_REG_ALARM_MON; _i2c.write((int)M41T62_addr, (char *)eep_dt, 1); _i2c.read((int)M41T62_addr, (char *)eep_dt, 1); eep_dt[1] = (eep_dt[0] & 0x07) | (sqw_dt << 4); eep_dt[0] = M41T62_REG_WDAY; _i2c.write((int)M41T62_addr, (char *)rtc_buf, 2); if (sqw_dt == RTC_SQW_NONE) { // Clear SQWE eep_dt[1] = eep_dt[0] & 0xbf; } else { // Set SQWE eep_dt[1] = eep_dt[0] | 0x40; } eep_dt[0] = M41T62_REG_ALARM_MON; _i2c.write((int)M41T62_addr, (char *)rtc_buf, 2); } uint8_t M41T62::bin2bcd (uint8_t dt) { uint8_t bcdhigh = 0; while (dt >= 10) { bcdhigh++; dt -= 10; } return ((uint8_t)(bcdhigh << 4) | dt); } uint8_t M41T62::bcd2bin (uint8_t dt) { uint8_t tmp = 0; tmp = ((uint8_t)(dt & (uint8_t)0xf0) >> (uint8_t)0x4) * 10; return (tmp + (dt & (uint8_t)0x0f)); }