Mktime localtime functions available for 8-Bit Single-Chip Microcomputer,

Mktime localtime functions available for 8-Bit Single-Chip Microcomputer,

Mktime localtime functions available for 8-bit single-chip microcomputer and source code

 

Recently I am working on an 8-Bit Single-Chip Microcomputer project, where the timestamp conversion function is used. This database function on a 32-bit machine solves the problem, I did not expect that there is no corresponding Library (time. h), there is no way to write it by yourself.

Objective: 1. meet the requirements of one to two pieces of data calculated by the mktime localtime library function; 2. Consider the low processing efficiency of the Eight-bit single chip microcomputer.

Share with you to make it easier for you to have the same requirements.

 

Test the gcc environment:

Test procedure:

1 # include <stdio. h> 2 # include <stdint. h> 3 # include <time. h> 4 # include <string. h> 5 6 # if 0 7 struct tm {8 int tm_sec;/* seconds after the minute, 0 to 60 9 (0-60 allows for the occasional leap second) */10 int tm_min;/* minutes after the hour, 0 to 59 */11 int tm_hour;/* hours since midnight, 0 to 23 */12 int tm_mday; /* day of the month, 1 to 31 */13 int tm_mon;/* months since Janua Ry, 0 to 11 */14 int tm_year;/* years since 1900 */15 // int tm_wday;/* days since Sunday, 0 to 6 */16 // int tm_yday;/* days since January 1, 0 to 365 */17 // int tm_isdst;/* Daylight Savings Time flag */18 }; 19 # endif 20 static const char mon_list [12] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 31, 30, 31 }; 21 static const char leap_mon_list [12] = {31, 29, 31, 30, 31, 30, 31, 31, 30, 30, 31 }; 22 23 /************************************* **************************************** ** 24 * Function Name: fun_mktime 25 * Description: Convert time to timestamp 26 * Input: 27 * Output: 28 * Other: 29 * Date: 2016.11.14 30 ************************************** **************************************** */31 int32_t fun_mktime (struct tm * pT) 32 {33 const char * pDays = NULL; 34 int32_t tmp = 0; 35 int16 _ T I = 0; 36 37 // calculate the total number of leap years 38 tmp = (pT-> tm_year/4-pT-> tm_year/100 + pT-> tm_year/400) -(1970/4-1970/100 + 1970/400); 39 40 // if the current year is a leap year, you need to subtract the leap year 41 if (pT-> tm_year % 4 = 0) & (pT-> tm_year % 100! = 0) | (pT-> tm_year % 400 = 0) 42 {43 tmp = tmp-1 + (pT-> tm_year-1970) * 365; 44 pDays = leap_mon_list; 45} 46 else 47 {48 tmp = tmp + (pT-> tm_year-1970) * 365; 49 pDays = mon_list; 50} 51 52 for (I = 0; I <pT-> tm_mon-1; I ++) 53 tmp + = pDays [I]; 54 55 tmp = tmp + pT-> tm_mday-1; 56 57 tmp = tmp * 24 + pT-> tm_hour; 58 59 tmp = tmp * 60 + pT-> tm_min; 60 61 tmp = tmp * 60 + pT-> tm_se C; 62 63 return tmp; 64} 65 66 /*********************************** **************************************** * *** 67 * Function Name: fun_localtime 68 * Description: Time Stamp converted to 69 * Input: struct tm * pT: Output Time buffer uint32_t tim: Current Time Stamp 70 * Output: 71 * Other: 72 * Date: 2016.11.14 73 ************************************** **************************************** */74 void fun_localtime (struct tm * pT, Int32_t tim) 75 {76 const char * pDays = NULL; 77 78 uint16_t index = 0; 79 80 memset (pT, 0, sizeof (* pT )); 81 82 // year initialization 83 if (tim> 0x5685C180L) // 84 {85 pT-> tm_year = 2016; 86 tim-= 0x5685C180L; 87} 88 else if (tim> 0x4B3D3B00L) // {90 pT-> tm_year = 2010; 91 tim-= 0x4B3D3B00L; 92} 93 else if (tim> 0x20.d4380l) // 2000-1-1 0: 0 94 {95 p T-> tm_year = 2000; 96 tim-= 0x0000d4380l; 97} 98 else 99 {100 pT-> tm_year = 1970; 101} 102 103 // now have year104 while (tim> = 1_l * 24*60*60) 105 {106 if (pT-> tm_year % 4 = 0) & (pT-> tm_year % 100! = 0) | (pT-> tm_year % 400 = 0) 107 tim-= 1_l * 24*60*60; 108 else 109 tim-= 365L * 24*60*60; 110 111 pT-> tm_year ++; 112} 113 114 365 // then 366*24*60*60 <tim <60115*24*60 * if (! (PT-> tm_year % 4 = 0) & (pT-> tm_year % 100! = 0) | (pT-> tm_year % 400 = 0) 116 & (tim> 365L * 24*60*60 )) 117 {118 tim-= 365L * 24*60*60; 119 pT-> tm_year ++; 120} 121 122 // this year is a leap year? 123 if (pT-> tm_year % 4 = 0) & (pT-> tm_year % 100! = 0) | (pT-> tm_year % 400 = 0) 124 pDays = leap_mon_list; 125 else 126 pDays = mon_list; 127 128 pT-> tm_mon = 1; 129 // now have mon130 while (tim> pDays [index] * 24L * 60*60) 131 {132 tim-= pDays [index] * 24L * 60*60; 133 index ++; 134 pT-> tm_mon ++; 135} 136 137 // now have days138 pT-> tm_mday = tim/(24L * 60*60) + 1; 139 tim = tim % (24L * 60*60); 140 141 // now have hour142 pT-> tm_hour = tim/(60*60 ); 143 tim = tim % (60*60); 144 145 // now have min 146 pT-> tm_min = tim/60; 147 tim = tim % 60; 148 149 pT-> tm_sec = tim; 150} 151 152 153 int main (void * parg) 154 {155 struct tm * pT = {0}; 156 time_t timep = 0; 157 uint32_t cur_tim = 0; 158 159 time (& timep); 160 161 pT = localtime (& timep); 162 163 printf ("linux time \ t = % d \ n ", (int32_t) timep); 164 pT-> tm_year + = 1900; 165 pT-> tm_mon + = 1; 166 printf ("fun_mktime \ t = % d \ n ", cur_tim = (uint32_t) fun_mktime (pT); 167 168 printf ("localtime \ t = % d-% d: % d \ n ", pT-> tm_year, pT-> tm_mon, pT-> tm_mday, pT-> tm_hour, pT-> tm_min, pT-> tm_sec); 169 memset (pT, 0, sizeof (* pT); 170 fun_localtime (pT, cur_tim); 171 printf ("fun_localtime \ t = % d-% d: % d \ n ", pT-> tm_year, pT-> tm_mon, pT-> tm_mday, pT-> tm_hour, pT-> tm_min, pT-> tm_sec ); 172 return 0; 173}

 

Test results:

 

linux time      = 1480133002fun_mktime      = 1480161802localtime       = 2016-11-26 12:3:22fun_localtime   = 2016-11-26 12:3:22

 

Linux time is the calculation result of the mktime library function. Because of the time zone processing, the difference between linux time and fun_mktime is 8*3600 seconds.

 

 

This function has been tested in C51 and meets the requirements.