M41T62 is a serial real-time clock (RTC) made by STMicroelectronics.
Dependents: LPC1114_data_logger Check_external_RTC LPC1114_barometer_with_data_logging
Diff: m41t62_rtc.cpp
- Revision:
- 0:2919f8bd90f3
- Child:
- 1:9d7702a887d3
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/m41t62_rtc.cpp Sat Jun 21 04:37:56 2014 +0000 @@ -0,0 +1,118 @@ +/* + * mbed library program + * Control M41T62 RTC Module + * + * Copyright (c) 2014 Kenji Arai / JH1PJL + * http://www.page.sannet.ne.jp/kenjia/index.html + * http://mbed.org/users/kenjiArai/ + * Created: June 21st, 2014 + * Revised: June 21st, 2014 + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, + * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE + * AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +/* + *---------------- REFERENCE ---------------------------------------------------------------------- + * http://www.st-japan.co.jp/web/jp/catalog/sense_power/FM151/CL1410/SC403/PF82507 + */ + +#include "mbed.h" +#include "m41t62_rtc.h" + + +// Register definition +#define M41T62_REG_SSEC 0 +#define M41T62_REG_SEC 1 +#define M41T62_REG_MIN 2 +#define M41T62_REG_HOUR 3 +#define M41T62_REG_WDAY 4 +#define M41T62_REG_DAY 5 +#define M41T62_REG_MON 6 +#define M41T62_REG_YEAR 7 +#define M41T62_REG_ALARM_MON 0xa +#define M41T62_REG_ALARM_DAY 0xb +#define M41T62_REG_ALARM_HOUR 0xc +#define M41T62_REG_ALARM_MIN 0xd +#define M41T62_REG_ALARM_SEC 0xe +#define M41T62_REG_FLAGS 0xf + +M41T62::M41T62 (PinName p_sda, PinName p_scl) : i2c(p_sda, p_scl) { + M41T62_addr = M41T62ADDR; +} + +M41T62::M41T62 (I2C& p_i2c) : i2c(p_i2c) { + M41T62_addr = M41T62ADDR; +} + +void M41T62::read_rtc (rtc_time *tm) { +uint8_t eep_dt; + + eep_dt = M41T62_REG_SSEC; + i2c_write_n_bytes((int)M41T62_addr, (char *)eep_dt, 1); + i2c_read_n_bytes((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 = bcd2bin(rtc_buf[M41T62_REG_YEAR]) + 100 + 1900; +} + +void M41T62::write_rtc (rtc_time *tm) { +uint8_t eep_dt; + + eep_dt = M41T62_REG_SSEC; + i2c_write_n_bytes((int)M41T62_addr, (char *)eep_dt, 1); + i2c_read_n_bytes((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((uint8_t)(tm->rtc_year % 100)); + 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_n_bytes((int)M41T62_addr, (char *)rtc_buf, 9); +} + +void M41T62::set_sq_wave (uint8_t sqw_dt) { +uint8_t eep_dt[2]; + + eep_dt[0] = M41T62_REG_WDAY; + i2c_write_n_bytes((int)M41T62_addr, (char *)eep_dt, 1); + i2c_read_n_bytes((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_n_bytes((int)M41T62_addr, (char *)rtc_buf, 2); +} + +void M41T62::i2c_read_n_bytes (int addr, char *dt, int n) { + i2c.read(addr, dt, n); +} + +void M41T62::i2c_write_n_bytes (int addr, char *dt, int n) { + i2c.write(addr, dt, n); +} + +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)); +} +