Library
Fork of mbed by
rtc_time.h
- Committer:
- gokmenascioglu
- Date:
- 2012-09-22
- Revision:
- 0:a8fa94490a0a
File content as of revision 0:a8fa94490a0a:
/* Title: time * Implementation of the C time.h functions * * Provides mechanisms to set and read the current time, based * on the microcontroller Real-Time Clock (RTC), plus some * standard C manipulation and formating functions. * * Example: * > #include "mbed.h" * > * > int main() { * > set_time(1256729737); // Set RTC time to Wed, 28 Oct 2009 11:35:37 * > * > while(1) { * > time_t seconds = time(NULL); * > * > printf("Time as seconds since January 1, 1970 = %d\n", seconds); * > * > printf("Time as a basic string = %s", ctime(&seconds)); * > * > char buffer[32]; * > strftime(buffer, 32, "%I:%M %p\n", localtime(&seconds)); * > printf("Time as a custom formatted string = %s", buffer); * > * > wait(1); * > } * > } */ /* mbed Microcontroller Library - rtc_time * Copyright (c) 2009 ARM Limited. All rights reserved. */ #include <time.h> #ifdef __cplusplus extern "C" { #endif #if 0 // for documentation only /* Function: time * Get the current time * * Returns the current timestamp as the number of seconds since January 1, 1970 * (the UNIX timestamp). The value is based on the current value of the * microcontroller Real-Time Clock (RTC), which can be set using <set_time>. * * Example: * > #include "mbed.h" * > * > int main() { * > time_t seconds = time(NULL); * > printf("It is %d seconds since January 1, 1970\n", seconds); * > } * * Variables: * t - Pointer to a time_t to be set, or NULL if not used * returns - Number of seconds since January 1, 1970 (the UNIX timestamp) */ time_t time(time_t *t); #endif /* Function: set_time * Set the current time * * Initialises and sets the time of the microcontroller Real-Time Clock (RTC) * to the time represented by the number of seconds since January 1, 1970 * (the UNIX timestamp). * * Example: * > #include "mbed.h" * > * > int main() { * > set_time(1256729737); // Set time to Wed, 28 Oct 2009 11:35:37 * > } * * Variables: * t - Number of seconds since January 1, 1970 (the UNIX timestamp) */ void set_time(time_t t); #if 0 // for documentation only /* Function: mktime * Converts a tm structure in to a timestamp * * Converts the tm structure in to a timestamp in seconds since January 1, 1970 * (the UNIX timestamp). The values of tm_wday and tm_yday of the tm structure * are also updated to their appropriate values. * * Example: * > #include "mbed.h" * > * > int main() { * > // setup time structure for Wed, 28 Oct 2009 11:35:37 * > struct tm t; * > t.tm_sec = 37; // 0-59 * > t.tm_min = 35; // 0-59 * > t.tm_hour = 11; // 0-23 * > t.tm_mday = 28; // 1-31 * > t.tm_mon = 9; // 0-11 * > t.tm_year = 109; // year since 1900 * > * > // convert to timestamp and display (1256729737) * > time_t seconds = mktime(&t); * > printf("Time as seconds since January 1, 1970 = %d\n", seconds); * > } * * Variables: * t - The tm structure to convert * returns - The converted timestamp */ time_t mktime(struct tm *t); #endif #if 0 // for documentation only /* Function: localtime * Converts a timestamp in to a tm structure * * Converts the timestamp pointed to by t to a (statically allocated) * tm structure. * * Example: * > #include "mbed.h" * > * > int main() { * > time_t seconds = 1256729737; * > struct tm *t = localtime(&seconds); * > } * * Variables: * t - Pointer to the timestamp * returns - Pointer to the (statically allocated) tm structure */ struct tm *localtime(const time_t *t); #endif #if 0 // for documentation only /* Function: ctime * Converts a timestamp to a human-readable string * * Converts a time_t timestamp in seconds since January 1, 1970 (the UNIX * timestamp) to a human readable string format. The result is of the * format: "Wed Oct 28 11:35:37 2009\n" * * Example: * > #include "mbed.h" * > * > int main() { * > time_t seconds = time(NULL); * > printf("Time as a string = %s", ctime(&seconds)); * > } * * Variables: * t - The timestamp to convert * returns - Pointer to a (statically allocated) string containing the * human readable representation, including a '\n' character */ char *ctime(const time_t *t); #endif #if 0 // for documentation only /* Function: strftime * Converts a tm structure to a custom format human-readable string * * Creates a formated string from a tm structure, based on a string format * specifier provided. * * Format Specifiers: * %S - Second (00-59) * %M - Minute (00-59) * %H - Hour (00-23) * %d - Day (01-31) * %m - Month (01-12) * %Y/%y - Year (2009/09) * * %A/%a - Weekday Name (Monday/Mon) * %B/%b - Month Name (January/Jan) * %I - 12 Hour Format (01-12) * %p - "AM" or "PM" * %X - Time (14:55:02) * %x - Date (08/23/01) * * Example: * > #include "mbed.h" * > * > int main() { * > time_t seconds = time(NULL); * > * > char buffer[32]; * > strftime(buffer, 32, "%I:%M %p\n", localtime(&seconds)); * > printf("Time as a formatted string = %s", buffer); * > } * * Variables: * buffer - String buffer to store the result * max - Maximum number of characters to store in the buffer * format - Format specifier string * t - Pointer to the tm structure to convert * returns - Number of characters copied */ size_t strftime(char *buffer, size_t max, const char *format, const struct tm *t); #endif #ifdef __cplusplus } #endif