David Smart / TimeInterface

A time interface class. This class replicates the normal time functions, but goes a couple of steps further. mbed library 82 and prior has a defective gmtime function. Also, this class enables access to setting the time, and adjusting the accuracy of the RTC.

Dependencies:   CalendarPage

Dependents:   CI-data-logger-server WattEye X10Svr SSDP_Server

TimeInterface.h@4:9cae2da8215e, 2015-01-19 (annotated)

Committer:
WiredHome
Date:
Mon Jan 19 13:36:15 2015 +0000
Revision:
4:9cae2da8215e
Parent:
3:49f36b489b64
Child:
6:c79cfe750416
include <ctime>

Who changed what in which revision?

UserRevisionLine numberNew contents of line
WiredHome 0:61112ca9193b 1
WiredHome 0:61112ca9193b 2 #ifndef TIMEINTERFACE_H
WiredHome 0:61112ca9193b 3 #define TIMEINTERFACE_H
WiredHome 0:61112ca9193b 4 #include "mbed.h"
WiredHome 4:9cae2da8215e 5 #include <ctime>
WiredHome 0:61112ca9193b 6
WiredHome 2:65e0a25c7551 7 #include "NTPClient.h" // ver 4 Donatien Garnier
WiredHome 2:65e0a25c7551 8
WiredHome 0:61112ca9193b 9 // Special Registers and their usage:
WiredHome 0:61112ca9193b 10 // GPREG0: 32 bits
WiredHome 0:61112ca9193b 11 // low word: time zone offset (-720 to +720)
WiredHome 0:61112ca9193b 12 // high word: 2's complement of low word for integrity checking
WiredHome 0:61112ca9193b 13 // GPREG1: 32 bits
WiredHome 0:61112ca9193b 14 // time_t value when the clock was last set
WiredHome 0:61112ca9193b 15
WiredHome 0:61112ca9193b 16
WiredHome 0:61112ca9193b 17 extern "C" {
WiredHome 0:61112ca9193b 18 #include "time.h"
WiredHome 0:61112ca9193b 19 }
WiredHome 0:61112ca9193b 20
WiredHome 0:61112ca9193b 21 struct tm_ex
WiredHome 0:61112ca9193b 22 {
WiredHome 0:61112ca9193b 23 int tm_sec; ///<! seconds, 0 to 59.
WiredHome 0:61112ca9193b 24 int tm_min; ///<! minutes, 0 to 59.
WiredHome 0:61112ca9193b 25 int tm_hour; ///<! hours, 0 to 23.
WiredHome 0:61112ca9193b 26 int tm_mday; ///<! monthday 1 to 31.
WiredHome 0:61112ca9193b 27 int tm_mon; ///<! month 0 to 11.
WiredHome 0:61112ca9193b 28 int tm_year; ///<! years since 1900.
WiredHome 0:61112ca9193b 29 int tm_wday; ///<! days since sunday 0 to 6.
WiredHome 0:61112ca9193b 30 int tm_yday; ///<! days since 1 Jan 0 to 365.
WiredHome 0:61112ca9193b 31 int tm_isdst; ///<! is daylight savings time.
WiredHome 0:61112ca9193b 32 int tm_tzo_min; ///<! localtime zone offset in minutes
WiredHome 0:61112ca9193b 33 };
WiredHome 0:61112ca9193b 34
WiredHome 0:61112ca9193b 35 /// TimeInterface class is much like the normal c-style time.h
WiredHome 0:61112ca9193b 36 /// interface, but is extended with time-zone support, and
WiredHome 0:61112ca9193b 37 /// clock-adjustment support (which permits tuning the clock)
WiredHome 0:61112ca9193b 38 /// for more accuracy.
WiredHome 0:61112ca9193b 39 ///
WiredHome 0:61112ca9193b 40 /// Within this class are the normal time.h methods, simply
WiredHome 0:61112ca9193b 41 /// exposed here for one consistent interface.
WiredHome 0:61112ca9193b 42 ///
WiredHome 0:61112ca9193b 43 /// @note This class uses the special battery backed registers
WiredHome 0:61112ca9193b 44 /// GPREG0 and GPREG1 for TimeInterface data.
WiredHome 0:61112ca9193b 45 ///
WiredHome 0:61112ca9193b 46 /// @note In mbed library ver 84, the gmtime method is defective,
WiredHome 0:61112ca9193b 47 /// and calls to this function return junk data. The
WiredHome 0:61112ca9193b 48 /// gmtime method in this library actually uses localtime,
WiredHome 0:61112ca9193b 49 /// but manages the time-zone offset as it does so.
WiredHome 0:61112ca9193b 50 ///
WiredHome 0:61112ca9193b 51 class TimeInterface
WiredHome 0:61112ca9193b 52 {
WiredHome 0:61112ca9193b 53 public:
WiredHome 0:61112ca9193b 54 TimeInterface();
WiredHome 0:61112ca9193b 55
WiredHome 0:61112ca9193b 56 ~TimeInterface();
WiredHome 0:61112ca9193b 57
WiredHome 0:61112ca9193b 58 /// Gets the system elapsed time in CLOCKS_PER_SEC tics.
WiredHome 0:61112ca9193b 59 ///
WiredHome 0:61112ca9193b 60 /// Divide the returned value by CLOCKS_PER_SEC to get time in seconds.
WiredHome 0:61112ca9193b 61 ///
WiredHome 0:61112ca9193b 62 /// @code
WiredHome 0:61112ca9193b 63 /// clock_t tstart, tend;
WiredHome 0:61112ca9193b 64 /// tstart = clock();
WiredHome 0:61112ca9193b 65 /// // do something long
WiredHome 0:61112ca9193b 66 /// tend = clock();
WiredHome 0:61112ca9193b 67 /// printf("Elapsed time is %5.3f\r\n", (float)(tend - tstart)/CLOCKS_PER_SEC);
WiredHome 0:61112ca9193b 68 /// @endcode
WiredHome 0:61112ca9193b 69 ///
WiredHome 0:61112ca9193b 70 /// @returns elapsed tics.
WiredHome 0:61112ca9193b 71 ///
WiredHome 0:61112ca9193b 72 clock_t clock(void);
WiredHome 0:61112ca9193b 73
WiredHome 0:61112ca9193b 74 /// Gets the current time as a time value, optionally writing it
WiredHome 0:61112ca9193b 75 /// to a provided buffer.
WiredHome 0:61112ca9193b 76 ///
WiredHome 0:61112ca9193b 77 /// This reads the real time clock and returns the current time.
WiredHome 0:61112ca9193b 78 ///
WiredHome 0:61112ca9193b 79 /// @code
WiredHome 0:61112ca9193b 80 /// time_t t_ref1, t_ref2, t_ref3;
WiredHome 0:61112ca9193b 81 /// t_ref1 = time(NULL); t_ref2 = t.time(); t.time(&t_ref3);
WiredHome 0:61112ca9193b 82 /// @endcode
WiredHome 0:61112ca9193b 83 ///
WiredHome 1:2ee90f546f54 84 /// @param[inout] timer is an optional pointer to a time_t value that will be written.
WiredHome 0:61112ca9193b 85 /// This pointer is ignored when NULL.
WiredHome 0:61112ca9193b 86 /// @returns time value.
WiredHome 0:61112ca9193b 87 ///
WiredHome 0:61112ca9193b 88 time_t time(time_t * timer = NULL);
WiredHome 0:61112ca9193b 89
WiredHome 1:2ee90f546f54 90 /// Gets the current local time as a time value, optionally writing it
WiredHome 1:2ee90f546f54 91 /// to a provided buffer.
WiredHome 1:2ee90f546f54 92 ///
WiredHome 1:2ee90f546f54 93 /// This reads the real time clock and returns the current time, adjusted
WiredHome 1:2ee90f546f54 94 /// for the local timezone.
WiredHome 1:2ee90f546f54 95 ///
WiredHome 1:2ee90f546f54 96 /// @code
WiredHome 1:2ee90f546f54 97 /// time_t t_ref2, t_ref3;
WiredHome 1:2ee90f546f54 98 /// t_ref2 = t.time(); t.timelocal(&t_ref3);
WiredHome 1:2ee90f546f54 99 /// @endcode
WiredHome 1:2ee90f546f54 100 ///
WiredHome 1:2ee90f546f54 101 /// @param[inout] timer is an optional pointer to a time_t value that will be written.
WiredHome 1:2ee90f546f54 102 /// This pointer is ignored when NULL.
WiredHome 1:2ee90f546f54 103 /// @returns the time value adjusted for the local time zone.
WiredHome 1:2ee90f546f54 104 ///
WiredHome 1:2ee90f546f54 105 time_t timelocal(time_t * timer = NULL);
WiredHome 1:2ee90f546f54 106
WiredHome 0:61112ca9193b 107 /// Convert a time value structure into an ASCII printable time Www Mmm dd hh:mm:ss yyyy
WiredHome 0:61112ca9193b 108 ///
WiredHome 0:61112ca9193b 109 /// @note Watch out for race conditions as this returns a pointer to a
WiredHome 0:61112ca9193b 110 /// shared buffer.
WiredHome 0:61112ca9193b 111 /// @note Unlike the standard ctime function, this version DOES NOT append
WiredHome 0:61112ca9193b 112 /// a newline character to the buffer.
WiredHome 0:61112ca9193b 113 ///
WiredHome 1:2ee90f546f54 114 /// @param[in] timeptr is a pointer to a tm structure containing the time to convert.
WiredHome 0:61112ca9193b 115 /// @returns a pointer to a private buffer containing the string.
WiredHome 0:61112ca9193b 116 ///
WiredHome 0:61112ca9193b 117 char * ctime(const time_t * timer);
WiredHome 0:61112ca9193b 118
WiredHome 0:61112ca9193b 119 /// Convert a tm structure into an ASCII printable time Www Mmm dd hh:mm:ss yyyy
WiredHome 0:61112ca9193b 120 ///
WiredHome 0:61112ca9193b 121 /// @note Watch out for race conditions as this returns a pointer to a
WiredHome 0:61112ca9193b 122 /// shared buffer.
WiredHome 0:61112ca9193b 123 /// @note Unlike the standard ctime function, this version DOES NOT append
WiredHome 0:61112ca9193b 124 /// a newline character to the buffer.
WiredHome 0:61112ca9193b 125 ///
WiredHome 1:2ee90f546f54 126 /// @param[in] timeptr is a pointer to a tm structure containing the time to convert.
WiredHome 0:61112ca9193b 127 /// @returns a pointer to a private buffer containing the string.
WiredHome 0:61112ca9193b 128 ///
WiredHome 0:61112ca9193b 129 char * asctime(const struct tm_ex *timeptr);
WiredHome 0:61112ca9193b 130
WiredHome 0:61112ca9193b 131 /// Compute the difference in seconds between two time values.
WiredHome 0:61112ca9193b 132 ///
WiredHome 1:2ee90f546f54 133 /// @param[in] end is the end time to compare to the beginning time.
WiredHome 1:2ee90f546f54 134 /// @param[in] beginning time is compared to the end time.
WiredHome 0:61112ca9193b 135 /// @return the difference in seconds, as a double.
WiredHome 0:61112ca9193b 136 ///
WiredHome 0:61112ca9193b 137 double difftime(time_t end, time_t beginning);
WiredHome 0:61112ca9193b 138
WiredHome 0:61112ca9193b 139 /// Convert the referenced time_t value to a tm structure in UTC/GMT format.
WiredHome 0:61112ca9193b 140 ///
WiredHome 0:61112ca9193b 141 /// @note Watch out for race conditions as this returns a pointer to a
WiredHome 0:61112ca9193b 142 /// shared buffer.
WiredHome 0:61112ca9193b 143 ///
WiredHome 1:2ee90f546f54 144 /// @param[in] timer is a pointer to a time_t structure to convert.
WiredHome 0:61112ca9193b 145 /// @returns pointer to a tm structure.
WiredHome 0:61112ca9193b 146 ///
WiredHome 0:61112ca9193b 147 struct tm_ex * gmtime(const time_t * timer);
WiredHome 0:61112ca9193b 148
WiredHome 0:61112ca9193b 149
WiredHome 0:61112ca9193b 150 /// Convert the referenced time_t value to a tm structure in local format.
WiredHome 0:61112ca9193b 151 ///
WiredHome 0:61112ca9193b 152 /// This method leverages the time zone offset applied with @see set_tzo().
WiredHome 0:61112ca9193b 153 ///
WiredHome 0:61112ca9193b 154 /// @note Watch out for race conditions as this returns a pointer to a
WiredHome 0:61112ca9193b 155 /// shared buffer.
WiredHome 0:61112ca9193b 156 ///
WiredHome 1:2ee90f546f54 157 /// @param[in] timer is a pointer to a time_t structure to convert.
WiredHome 0:61112ca9193b 158 /// @returns pointer to a tm structure.
WiredHome 0:61112ca9193b 159 ///
WiredHome 0:61112ca9193b 160 struct tm_ex * localtime(const time_t * timer);
WiredHome 0:61112ca9193b 161
WiredHome 0:61112ca9193b 162 /// Convert a tm_ex structure (an extended time structure) to a time_t
WiredHome 0:61112ca9193b 163 /// value.
WiredHome 0:61112ca9193b 164 ///
WiredHome 1:2ee90f546f54 165 /// @param[in] timeptr is a pointer to a tm_ex structure.
WiredHome 0:61112ca9193b 166 /// @returns the computed time_t value.
WiredHome 0:61112ca9193b 167 ///
WiredHome 0:61112ca9193b 168 time_t mktime(struct tm_ex * timeptr);
WiredHome 0:61112ca9193b 169
WiredHome 0:61112ca9193b 170 /// Presents a time value in a user specified format, into a user specified buffer.
WiredHome 0:61112ca9193b 171 ///
WiredHome 1:2ee90f546f54 172 /// @param[out] ptr is a pointer to the user buffer.
WiredHome 1:2ee90f546f54 173 /// @param[in] maxsize is the size of the user buffer.
WiredHome 1:2ee90f546f54 174 /// @param[in] format is a pointer to the special strftime format specification.
WiredHome 1:2ee90f546f54 175 /// @param[in] timeptr is a pointer to the tm_ex structure.
WiredHome 0:61112ca9193b 176 /// @returns the total number of characters copied into the buffer.
WiredHome 0:61112ca9193b 177 ///
WiredHome 0:61112ca9193b 178 size_t strftime(char * ptr, size_t maxsize, const char * format, const struct tm_ex * timeptr);
WiredHome 0:61112ca9193b 179
WiredHome 0:61112ca9193b 180 // time zone functions
WiredHome 0:61112ca9193b 181
WiredHome 0:61112ca9193b 182 /// Set the internal RTC (clock) to the time value. The time value
WiredHome 0:61112ca9193b 183 /// should be the UTC time, which then permits gmtime and
WiredHome 0:61112ca9193b 184 /// localtime to be used appropriately.
WiredHome 0:61112ca9193b 185 ///
WiredHome 2:65e0a25c7551 186 /// @param[in] t should be the UTC time value to set the clock to. If the available
WiredHome 0:61112ca9193b 187 /// time value is local time, the optional time zone offset can
WiredHome 2:65e0a25c7551 188 /// be provided so the system clock is UTC.
WiredHome 1:2ee90f546f54 189 /// @param[in] tzo is the optional time zone offset in minutes when it is in
WiredHome 0:61112ca9193b 190 /// the range of -720 to +720 (-12 hours to + 12 hours). Any
WiredHome 0:61112ca9193b 191 /// other value is illegal and no change will be made.
WiredHome 0:61112ca9193b 192 ///
WiredHome 0:61112ca9193b 193 void set_time(time_t t, int16_t tzo_min = 0);
WiredHome 0:61112ca9193b 194
WiredHome 0:61112ca9193b 195 /// Set the time zone offset in minutes.
WiredHome 0:61112ca9193b 196 ///
WiredHome 0:61112ca9193b 197 /// This API should be used before any other methods that fetch
WiredHome 0:61112ca9193b 198 /// the RTC info.
WiredHome 0:61112ca9193b 199 ///
WiredHome 1:2ee90f546f54 200 /// @param[in] tzo is the time zone offset in minutes when it is in
WiredHome 0:61112ca9193b 201 /// the range of -720 to +720 (-12 hours to + 12 hours). Any
WiredHome 0:61112ca9193b 202 /// other value is illegal and no change will be made.
WiredHome 0:61112ca9193b 203 ///
WiredHome 0:61112ca9193b 204 void set_tzo_min(int16_t tzo_min);
WiredHome 0:61112ca9193b 205
WiredHome 0:61112ca9193b 206 /// Get the time zone offset in minutes.
WiredHome 0:61112ca9193b 207 ///
WiredHome 0:61112ca9193b 208 /// @returns the time zone offset value in minutes. If the tzo was
WiredHome 0:61112ca9193b 209 /// never initialized, this returns zero.
WiredHome 0:61112ca9193b 210 ///
WiredHome 0:61112ca9193b 211 int16_t get_tzo_min(void);
WiredHome 0:61112ca9193b 212
WiredHome 3:49f36b489b64 213 /// Set the clock for local time to report whether the current
WiredHome 3:49f36b489b64 214 /// mode is standard or daylight savings time.
WiredHome 3:49f36b489b64 215 ///
WiredHome 3:49f36b489b64 216 /// return values for localtime will then be adjusted not only
WiredHome 3:49f36b489b64 217 /// for the time zone offset, but for dst.
WiredHome 3:49f36b489b64 218 ///
WiredHome 3:49f36b489b64 219 /// @param[in] dst is a boolean that should be set when dst is
WiredHome 3:49f36b489b64 220 /// the active mode.
WiredHome 3:49f36b489b64 221 ///
WiredHome 3:49f36b489b64 222 void set_dst(bool dst);
WiredHome 3:49f36b489b64 223
WiredHome 3:49f36b489b64 224 /// Get the current clock mode for daylight savings time.
WiredHome 3:49f36b489b64 225 ///
WiredHome 3:49f36b489b64 226 /// @returns true if clock is in dst mode.
WiredHome 3:49f36b489b64 227 ///
WiredHome 3:49f36b489b64 228 bool get_dst(void);
WiredHome 3:49f36b489b64 229
WiredHome 0:61112ca9193b 230 /// Get the time value when the clock was last set. This is most
WiredHome 0:61112ca9193b 231 /// often used in calibration of the clock.
WiredHome 0:61112ca9193b 232 ///
WiredHome 0:61112ca9193b 233 /// @returns time last set as a UTC time value.
WiredHome 0:61112ca9193b 234 ///
WiredHome 0:61112ca9193b 235 time_t get_timelastset(void);
WiredHome 0:61112ca9193b 236
WiredHome 0:61112ca9193b 237 /// get_cal will return the calibration register value
WiredHome 0:61112ca9193b 238 ///
WiredHome 0:61112ca9193b 239 /// This is the raw register value as a signed 32-bit value (even though
WiredHome 0:61112ca9193b 240 /// it is actually a 17-bit unsigned value with an additional 'direction' flag).
WiredHome 0:61112ca9193b 241 ///
WiredHome 0:61112ca9193b 242 /// @returns calibration settings ranging from -131071 to +131071
WiredHome 0:61112ca9193b 243 ///
WiredHome 0:61112ca9193b 244 int32_t get_cal();
WiredHome 0:61112ca9193b 245
WiredHome 0:61112ca9193b 246 /// set_cal will set the calibration register value
WiredHome 0:61112ca9193b 247 ///
WiredHome 0:61112ca9193b 248 /// This accepts a signed value to be used to set the calibration
WiredHome 0:61112ca9193b 249 /// registers. Setting the calibration value to zero disables the
WiredHome 0:61112ca9193b 250 /// calibration function.
WiredHome 0:61112ca9193b 251 ///
WiredHome 0:61112ca9193b 252 /// It is important to know the register function in order to use
WiredHome 0:61112ca9193b 253 /// this command, and this API is normally not used by external
WiredHome 0:61112ca9193b 254 /// application code. @See AdjustBySeconds for a user-friendly
WiredHome 0:61112ca9193b 255 /// API.
WiredHome 0:61112ca9193b 256 ///
WiredHome 1:2ee90f546f54 257 /// @param[in] calibration value to use ranging from -131071 to +131071
WiredHome 0:61112ca9193b 258 /// @returns nothing
WiredHome 0:61112ca9193b 259 ///
WiredHome 0:61112ca9193b 260 void set_cal(int32_t calibration);
WiredHome 0:61112ca9193b 261
WiredHome 0:61112ca9193b 262 /// adjust_sec adjusts both the time and the calibration by seconds
WiredHome 0:61112ca9193b 263 ///
WiredHome 0:61112ca9193b 264 /// This will take a signed value, which is the current adjustment in seconds
WiredHome 0:61112ca9193b 265 /// to put the clock on the correct time. So, if the clock is behind by
WiredHome 0:61112ca9193b 266 /// 3 seconds, the value should be +3 to advance the clock accordingly.
WiredHome 0:61112ca9193b 267 /// It will then adjust the time, and it will attempt to adjust the
WiredHome 0:61112ca9193b 268 /// calibration factor to make the time more accurate.
WiredHome 0:61112ca9193b 269 ///
WiredHome 0:61112ca9193b 270 /// The adjustment can only be made if it has retained when the clock was
WiredHome 0:61112ca9193b 271 /// last set, in order to know by how much to adjust it. It is also most
WiredHome 0:61112ca9193b 272 /// accurate if several days have elapsed since the time was set.
WiredHome 0:61112ca9193b 273 ///
WiredHome 0:61112ca9193b 274 /// @note The current version only works if the calibration value
WiredHome 0:61112ca9193b 275 /// is zero when this adjustment is made.
WiredHome 0:61112ca9193b 276 ///
WiredHome 1:2ee90f546f54 277 /// @param[in] adjustSeconds is the signed value by which to adjust the time to
WiredHome 0:61112ca9193b 278 /// correct it to the current actual time.
WiredHome 0:61112ca9193b 279 /// @returns true if the adjustment was made
WiredHome 0:61112ca9193b 280 /// @returns false if the adjustment could not be made
WiredHome 0:61112ca9193b 281 ///
WiredHome 0:61112ca9193b 282 bool adjust_sec(int32_t adjustSeconds);
WiredHome 0:61112ca9193b 283
WiredHome 2:65e0a25c7551 284 /// Set the clock from an internet source (blocking)
WiredHome 2:65e0a25c7551 285 ///
WiredHome 2:65e0a25c7551 286 /// This function is the interface to NTPClient.
WiredHome 2:65e0a25c7551 287 /// Blocks until completion
WiredHome 2:65e0a25c7551 288 ///
WiredHome 2:65e0a25c7551 289 /// @param[in] host NTP server IPv4 address or hostname (will be resolved via DNS)
WiredHome 2:65e0a25c7551 290 /// @param[in] port port to use; defaults to 123
WiredHome 2:65e0a25c7551 291 /// @param[in] timeout waiting timeout in ms (osWaitForever for blocking function, not recommended)
WiredHome 2:65e0a25c7551 292 /// @return 0 on success, NTP error code (<0) on failure
WiredHome 2:65e0a25c7551 293 ///
WiredHome 2:65e0a25c7551 294 NTPResult setTime(const char* host, uint16_t port = NTP_DEFAULT_PORT, uint32_t timeout = NTP_DEFAULT_TIMEOUT);
WiredHome 2:65e0a25c7551 295
WiredHome 2:65e0a25c7551 296 // ntp interface functions
WiredHome 0:61112ca9193b 297 private:
WiredHome 0:61112ca9193b 298 char result[30]; // holds the converted to text time string
WiredHome 0:61112ca9193b 299 time_t tresult; // holds the converted time structure.
WiredHome 0:61112ca9193b 300 struct tm_ex tm_ext;
WiredHome 0:61112ca9193b 301 };
WiredHome 0:61112ca9193b 302
WiredHome 0:61112ca9193b 303 #endif // TIMEINTERFACE_H