Diff: ds3232m.h

Revision:

0:30a7faf58768

Child:

1:0975d4a9b513

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ds3232m.h	Mon Dec 08 20:15:16 2014 +0000
@@ -0,0 +1,248 @@
+#ifndef DS3232M_H
+#define DS3232M_H
+
+/*
+Maxim Integrated DS3232M, fully integrated Real Time Clock chip.  The
+chip contains an I2C interface, compatable time-base registers to 
+the DS1307 and M11T41, a super-accurate internal oscillator, 2 alarms
+and 236 bytes of user defined battery-backed RAM.
+*/
+
+/** Class ds3232m implements the real time clock
+ *
+ *
+ *
+ */
+ 
+class ds3232m {
+    
+public:
+    /** Structure which is used to exchange the time and date
+     */
+    typedef struct {
+        int sec;        /*!< seconds [0..59] */
+        int min;        /*!< minutes {0..59] */
+        int hour;       /*!< hours [0..23] */
+        int wday;       /*!< weekday [1..7, where 1 = sunday, 2 = monday, ... */
+        int date;       /*!< day of month [0..31] */
+        int mon;        /*!< month of year [1..12] */
+        int year;       /*!< year [2000..2255] */
+    } Time_rtc;
+
+protected:
+    I2C*    _i2c_;
+
+//    static const char *m_weekDays[];
+
+public:
+    /**
+     * Constructor with default i2c clock speed
+     * - Fixed at I2C address 0x80
+     * - I2C speed set to 400KHz
+     *
+     * @param sda - mbed I2C interface pin
+     * @param scl - mbed I2C interface pin
+     */
+    ds3232m(PinName sda, PinName scl);
+    /**
+     * Constructor with i2c clock setting option
+     * - Fixed at I2C address 0x80
+     * - I2C speed set by user
+     *
+     * @param sda - mbed I2C interface pin
+     * @param scl - mbed I2C interface pin
+     * @param set_I2C_frequency
+     */
+    ds3232m(PinName sda, PinName scl, int i2cFrequency);
+    /**
+     * Destructor
+     *
+     * @param --none--
+     */
+    ~ds3232m();
+    /**
+     * See if temperature conversion is busy or not
+     * 
+     * @param --none--
+     *
+     * @return busy_flag - Temperature Conversion is busy
+     *  - true = busy
+     *  - false = ready
+    */  
+    bool checkTempBusy();
+    /**
+     * Start a temperature conversion cycle
+     *  - Note: only 1 conversion per second allowed
+     * 
+     * @param --none--
+     *
+     * @return busy_flag Temperature Conversion is Busy
+     *  - true = started new conversion
+     *  - false = already busy from previous converstion start
+    */ 
+    bool startTempCycle();
+    /**
+     * Get the chip temperature from the DS3232M
+     * 
+     * @param --none--
+     *
+     * @return Temperature 0.25degC accuracy
+     * @return 255.0 if temperature conversion not complete (still busy)
+    */ 
+    float getTemperature();
+    /**
+     * Get seconds register from DS3232M
+     * 
+     * @param --none--
+     *
+     * @return BCD-to-decimal corrected seconds register
+    */ 
+    int getSeconds();
+    /**
+     * Clear out all 236 bytes of user RAM, from address 0x14 to 0xff
+     *  - 00h is put in all user RAM area
+     * 
+     * @param --none--
+     *
+     * @return --none--
+    */ 
+    void clearRAM();
+    /**
+     * Retrieve data from DS3232M's user RAM area
+     *  - addresses range 0x14 - 0xfd
+     *  - CRC is checked of entire RAM contents
+     * 
+     * @param buffer pointer
+     * @param offset into DS3232M's RAM (range 0x14 = 0xfd)
+     * @param length number of bytes to get
+     *
+     * @return 00 = no error
+     * @return 01 = length + offset is over the highest user RAM location
+     * @return 02 = offset < 0x14
+     * @return 04 = length = 0 
+     * @return 08 = crc error occured from LoadRTCRam()
+    */
+    int getUserRAM(char *buffer, int offset, int length);
+    /**
+     * Store data DS3232M's user RAM area
+     *  - addresses range 0x14 - 0xfd
+     *  - CRC is added to the last 2 locations using addCRC16()
+     * 
+     * @param buffer pointer
+     * @param offset into DS3232M's RAM (range 0x14 = 0xfd)
+     * @param length number of bytes to store
+     *
+     * @return 00 = no error
+     * @return 01 = length + offset is over the highest user RAM location
+     * @return 02 = offset < 0x14
+     * @return 04 = length = 0 
+    */
+    int putUserRAM(char *buffer, int offset, int length);
+    /**
+     * Calculate CRC16
+     * 
+     * @param input buffer pointer
+     * @param address offset into buffer
+     * @param length number of bytes to calculate
+     *
+     * @return CRC16 value
+    */
+    uint16_t calculateCRC16(char input[], int offset, int length);
+    /**
+     * Turn on/off the 32KHz output pin 
+     *  - with option to keep 32KHz output ON during battery backup
+     *  - This pin is push-pull, no pullup is required
+     * 
+     * @param ena
+     *  - true = enable during normal operation
+     *  - false = disable 32KHz output pin during normal operation
+     * @param batt
+     *  - true = enable 32KHz output pin during battery backup mode
+     *  - false = disable 32KHz output pin during battery backup mode
+     *  - Note: "ena" must be true or else batt is ignored
+     *
+     * @return --none--
+    */ 
+    void set32KhzOutput(bool ena, bool batt);
+    /**
+     * Turn on/off the 1Hz output pin
+     *  - with option to keep 1Hz output ON during battery backup
+     *  - This pin is open-drain
+     *  - Requires a pullup resistor to Vcc or the backup battery
+     * 
+     * @param ena  
+     *  - true = enable 1Hz output pin during normal operation
+     *  - false = disable 1Hz output pin during normal operation
+     * @param batt
+     *  - true = enable 1Hz output pin during battery backup mode
+     *  - false = disable 1Hz output pin during battery backup mode
+     *  - Note: "ena" must be true or else batt is ignored
+     *
+     * @return --none--
+    */
+    void set1hzOutput(bool ena, bool batt);
+    /**
+     * Turn on/off the main oscillator during battery backup mode
+     *  - The oscillator always runs when Vcc is valid
+     * 
+     * @param batt 
+     *  - true = enable the oscillator during battery backup mode
+     *  - false = disable the oscillator during battery backup mode
+     *
+     * @return --none--
+    */
+    void enableBattClock(bool batt);
+    /** 
+     * Read all of the current time registers from the DS3232M
+     *
+     * @param time_structure - will be filled with the time from DS3232M
+     *
+     * @returns --none--
+     */
+    void getTime(Time_rtc& time);
+    /** 
+     * Write all of the current time registers into the DS3232M
+     *
+     * @param time_structure - will be filled with the time into the DS3232M
+     *
+     * @returns --none--
+     */
+    void setTime(Time_rtc& time);
+    /** 
+     * Load the entire contents of the DS3232M into dedicated buffer RTCbuffer[]
+     *   - includes time registers, alarm registers and user RAM
+     *
+     * @param --none--
+     *
+     * @return CRC_Status - pass/fail of CRC readback of user RAM data
+     *  - true = CRC is ok
+     *  - false = CRC failed
+     */
+    bool LoadRTCRam();
+    /** 
+     * Dedicated buffer that mirrors the RTC's entire contents
+     *   - loaded by LoadRTCRam()
+     *
+     * @param --none--
+     *
+     * @return --none--
+     */
+    char RTCbuffer[256];
+
+private:
+    void getControlStatusRegs();
+    char RtcCtlReg;
+    char RtcStatReg;
+    void addCRC16();
+
+// BCD-Decimal Conversions, hacked from Henry Leinen's RTC-DS1307 library
+    static int BCDToDec(int dat) {
+        return ((dat & 0xF0) >> 4) * 10 + (dat & 0x0F);
+    }
+
+    static int DecToBCD(int dat) {
+        return (dat % 10) + ((dat / 10) << 4);
+    }
+};
+
+#endif // DS3232M_H