m41t62_rtc.h

00001 /*
00002  * mbed library program
00003  *  Control M41T62 RTC Module
00004  *  STMicroelectronics
00005  *
00006  * Copyright (c) 2014,'15,'17,'20 Kenji Arai / JH1PJL
00007  *  http://www7b.biglobe.ne.jp/~kenjia/
00008  *  https://os.mbed.com/users/kenjiArai/
00009  *      Created: June       21st, 2014
00010  *      Revised: August      7th, 2020
00011  */
00012 
00013 /*
00014  *---------------- REFERENCE ---------------------------------------------------
00015  *  http://www.st-japan.co.jp/web/jp/
00016  *                  catalog/sense_power/FM151/CL1410/SC403/PF82507
00017  *  http://strawberry-linux.com/catalog/items?code=12062
00018  */
00019 
00020 #ifndef M41T62_H
00021 #define M41T62_H
00022 
00023 #include "mbed.h"
00024 
00025 // RTC STmicro M41T62
00026 // Address b7=1,b6=1,b5=0,b4=1,b3=0,b2=0,b1=0, b0=R/W
00027 #define M41T62ADDR  (0x68 << 1) // No other choice
00028 
00029 // Register definition
00030 #define M41T62_REG_SSEC         0x0
00031 #define M41T62_REG_SEC          0x1
00032 #define M41T62_REG_MIN          0x2
00033 #define M41T62_REG_HOUR         0x3
00034 #define M41T62_REG_WDAY         0x4
00035 #define M41T62_REG_DAY          0x5
00036 #define M41T62_REG_MON          0x6
00037 #define M41T62_REG_YEAR         0x7
00038 #define M41T62_REG_CALIB        0x8
00039 #define M41T62_REG_WDT          0x9
00040 #define M41T62_REG_ALARM_MON    0xa
00041 #define M41T62_REG_ALARM_DAY    0xb
00042 #define M41T62_REG_ALARM_HOUR   0xc
00043 #define M41T62_REG_ALARM_MIN    0xd
00044 #define M41T62_REG_ALARM_SEC    0xe
00045 #define M41T62_REG_FLAGS        0xf
00046 
00047 // Buffer size
00048 #define RTC_BUF_SIZ            (M41T62_REG_FLAGS + 5)
00049 
00050 typedef enum {
00051     RTC_SQW_NONE = 0,
00052     RTC_SQW_32KHZ,
00053     RTC_SQW_8KHZ,
00054     RTC_SQW_4KHZ,
00055     RTC_SQW_2KHZ,
00056     RTC_SQW_1KHZ,
00057     RTC_SQW_512HZ,
00058     RTC_SQW_256HZ,
00059     RTC_SQW_128HZ,
00060     RTC_SQW_64HZ,
00061     RTC_SQW_32HZ,
00062     RTC_SQW_16HZ,
00063     RTC_SQW_8HZ,
00064     RTC_SQW_4HZ,
00065     RTC_SQW_2HZ,
00066     RTC_SQW_1HZ
00067 } sq_wave_t;
00068 
00069 /** Interface for RTC (I2C Interface)  STMicroelectronics M41T62
00070  *
00071  *  Standalone type RTC via I2C interface
00072  *
00073  * @code
00074  * #include "mbed.h"
00075  * #include "m41t62_rtc.h"
00076  *
00077  * // I2C Communication
00078  *  M41T62      m41t62(dp5,dp27);   // STmicro RTC(M41T62) SDA, SCL
00079  * // If you connected I2C line not only this device but also other devices,
00080  * //     you need to declare following method.
00081  *  I2C         i2c(dp5,dp27);      // SDA, SCL
00082  *  M41T62      m41t62(i2c);        // STmicro RTC(M41T62)
00083  *
00084  * int main() {
00085  * tm t;
00086  * time_t seconds;
00087  * char buf[40];
00088  *
00089  *   m41t62.set_sq_wave(RTC_SQW_NONE); // Stop output for more low current
00090  *   while(1){
00091  *      m41t62.read_rtc_std(&t);       // read RTC data
00092  *      seconds = mktime(&t);
00093  *      strftime(buf, 40, "%I:%M:%S %p (%Y/%m/%d)", localtime(&seconds));
00094  *      printf("Date: %s\r\n", buf);
00095  *   }
00096  * }
00097  * @endcode
00098  */
00099 
00100 class M41T62
00101 {
00102 public:
00103 
00104     typedef struct {    // BCD format
00105         uint8_t rtc_seconds;
00106         uint8_t rtc_minutes;
00107         uint8_t rtc_hours;
00108         uint8_t rtc_weekday;
00109         uint8_t rtc_date;
00110         uint8_t rtc_month;
00111         uint8_t rtc_year_raw;
00112         uint16_t rtc_year;
00113     } rtc_time;
00114 
00115     /** Configure data pin (with other devices on I2C line)
00116       * @param data SDA and SCL pins
00117       */
00118     M41T62(PinName p_sda, PinName p_scl);
00119 
00120     /** Configure data pin (with other devices on I2C line)
00121       * @param I2C previous definition
00122       */
00123     M41T62(I2C& p_i2c);
00124 
00125     /** Read RTC data with Standard C "struct tm" format
00126       * @param tm (data save area)
00127       * @return none but all data in tm
00128       */
00129     void read_rtc_std(tm *);
00130     void get_time_rtc(tm *);
00131 
00132     /** Write data to RTC data with Standard C "struct tm" format
00133       * @param tm (save writing data)
00134       * @return none but all data in tm
00135       */
00136     void write_rtc_std(tm *);
00137     void set_time_rtc(tm *);
00138 
00139     /** Set Alarm / IRQ time
00140       * @param next time (unit: minutes) from now on minimum = 2 minuteｓ!!
00141       * @return none
00142       */
00143     void set_next_IRQ(uint16_t time);
00144 
00145     /** Clear Alarm / IRQ pin interrupt
00146       * @param none
00147       * @return none
00148       */
00149     void clear_IRQ(void);
00150 
00151     /** Read RTC data with own format
00152       * @param tm (data save area)
00153       * @return none but all data in tm
00154       */
00155     void read_rtc_direct(rtc_time *);
00156 
00157     /** Read RTC data with own format
00158       * @param tm (save writing data)
00159       * @return none but all data in tm
00160       */
00161     void write_rtc_direct(rtc_time *);
00162 
00163     /** Set I2C clock frequency
00164       * @param freq.
00165       * @return none
00166       */
00167     void frequency(int);
00168 
00169     /** Control Square wave output port
00170       * @param output_mode 
00171       * @return none
00172       */
00173     void set_sq_wave(sq_wave_t);
00174 
00175 protected:
00176     I2C *_i2c_p;
00177     I2C &_i2c;
00178 
00179     uint8_t bin2bcd(uint8_t);
00180     uint8_t bcd2bin(uint8_t);
00181     void set_alarm_reg (uint16_t time);
00182 
00183 private:
00184     uint8_t M41T62_addr;
00185     uint8_t rtc_buf[RTC_BUF_SIZ];   // buffer for RTC
00186 
00187 };
00188 
00189 #endif      // M41T62_H