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December 9, 2014 15:18
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/* | |
* ds1302.c: | |
* Real Time clock | |
* | |
* Copyright (c) 2013 Gordon Henderson. | |
*********************************************************************** | |
* This file is part of wiringPi: | |
* https://projects.drogon.net/raspberry-pi/wiringpi/ | |
* | |
* wiringPi is free software: you can redistribute it and/or modify | |
* it under the terms of the GNU Lesser General Public License as published by | |
* the Free Software Foundation, either version 3 of the License, or | |
* (at your option) any later version. | |
* | |
* wiringPi is distributed in the hope that it will be useful, | |
* but WITHOUT ANY WARRANTY; without even the implied warranty of | |
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
* GNU Lesser General Public License for more details. | |
* | |
* You should have received a copy of the GNU Lesser General Public License | |
* along with wiringPi. If not, see <http://www.gnu.org/licenses/>. | |
*********************************************************************** | |
*/ | |
#include <stdio.h> | |
#include <stdlib.h> | |
#include <stdint.h> | |
#include <string.h> | |
#include <time.h> | |
#include <wiringPi.h> | |
#include <ds1302.h> | |
// Register defines | |
#define RTC_SECS 0 | |
#define RTC_MINS 1 | |
#define RTC_HOURS 2 | |
#define RTC_DATE 3 | |
#define RTC_MONTH 4 | |
#define RTC_DAY 5 | |
#define RTC_YEAR 6 | |
#define RTC_WP 7 | |
#define RTC_TC 8 | |
#define RTC_BM 31 | |
static unsigned int masks [] = { 0x7F, 0x7F, 0x3F, 0x3F, 0x1F, 0x07, 0xFF } ; | |
/* | |
* bcdToD: dToBCD: | |
* BCD decode/encode | |
********************************************************************************* | |
*/ | |
static int bcdToD (unsigned int byte, unsigned int mask) | |
{ | |
unsigned int b1, b2 ; | |
byte &= mask ; | |
b1 = byte & 0x0F ; | |
b2 = ((byte >> 4) & 0x0F) * 10 ; | |
return b1 + b2 ; | |
} | |
static unsigned int dToBcd (unsigned int byte) | |
{ | |
return ((byte / 10) << 4) + (byte % 10) ; | |
} | |
/* | |
* ramTest: | |
* Simple test of the 31 bytes of RAM inside the DS1302 chip | |
********************************************************************************* | |
*/ | |
static int ramTestValues [] = | |
{ 0x00, 0xFF, 0xAA, 0x55, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x00, 0xF0, 0x0F, -1 } ; | |
static int ramTest (void) | |
{ | |
int addr ; | |
int got ; | |
int i = 0 ; | |
int errors = 0 ; | |
int testVal ; | |
printf ("DS1302 RAM TEST\n") ; | |
testVal = ramTestValues [i] ; | |
while (testVal != -1) | |
{ | |
for (addr = 0 ; addr < 31 ; ++addr) | |
ds1302ramWrite (addr, testVal) ; | |
for (addr = 0 ; addr < 31 ; ++addr) | |
if ((got = ds1302ramRead (addr)) != testVal) | |
{ | |
printf ("DS1302 RAM Failure: Address: %2d, Expected: 0x%02X, Got: 0x%02X\n", | |
addr, testVal, got) ; | |
++errors ; | |
} | |
testVal = ramTestValues [++i] ; | |
} | |
for (addr = 0 ; addr < 31 ; ++addr) | |
ds1302ramWrite (addr, addr) ; | |
for (addr = 0 ; addr < 31 ; ++addr) | |
if ((got = ds1302ramRead (addr)) != addr) | |
{ | |
printf ("DS1302 RAM Failure: Address: %2d, Expected: 0x%02X, Got: 0x%02X\n", | |
addr, addr, got) ; | |
++errors ; | |
} | |
if (errors == 0) | |
printf ("-- DS1302 RAM TEST: OK\n") ; | |
else | |
printf ("-- DS1302 RAM TEST FAILURE. %d errors.\n", errors) ; | |
return 0 ; | |
} | |
/* | |
* setLinuxClock: | |
* Set the Linux clock from the hardware | |
********************************************************************************* | |
*/ | |
static int setLinuxClock (void) | |
{ | |
char dateTime [20] ; | |
char command [64] ; | |
int clock [8] ; | |
printf ("Setting the Linux Clock from the DS1302... ") ; fflush (stdout) ; | |
ds1302clockRead (clock) ; | |
// [MMDDhhmm[[CC]YY][.ss]] | |
sprintf (dateTime, "%02d%02d%02d%02d%02d%02d.%02d", | |
bcdToD (clock [RTC_MONTH], masks [RTC_MONTH]), | |
bcdToD (clock [RTC_DATE], masks [RTC_DATE]), | |
bcdToD (clock [RTC_HOURS], masks [RTC_HOURS]), | |
bcdToD (clock [RTC_MINS], masks [RTC_MINS]), | |
20, | |
bcdToD (clock [RTC_YEAR], masks [RTC_YEAR]), | |
bcdToD (clock [RTC_SECS], masks [RTC_SECS])) ; | |
sprintf (command, "/bin/date %s", dateTime) ; | |
system (command) ; | |
return 0 ; | |
} | |
/* | |
* setDSclock: | |
* Set the DS1302 block from Linux time | |
********************************************************************************* | |
*/ | |
static int setDSclock (void) | |
{ | |
struct tm t ; | |
time_t now ; | |
int clock [8] ; | |
printf ("Setting the clock in the DS1302 from Linux time... ") ; | |
now = time (NULL) ; | |
gmtime_r (&now, &t) ; | |
clock [ 0] = dToBcd (t.tm_sec) ; // seconds | |
clock [ 1] = dToBcd (t.tm_min) ; // mins | |
clock [ 2] = dToBcd (t.tm_hour) ; // hours | |
clock [ 3] = dToBcd (t.tm_mday) ; // date | |
clock [ 4] = dToBcd (t.tm_mon + 1) ; // months 0-11 --> 1-12 | |
clock [ 5] = dToBcd (t.tm_wday + 1) ; // weekdays (sun 0) | |
clock [ 6] = dToBcd (t.tm_year - 100) ; // years | |
clock [ 7] = 0 ; // W-Protect off | |
ds1302clockWrite (clock) ; | |
printf ("OK\n") ; | |
return 0 ; | |
} | |
int main (int argc, char *argv []) | |
{ | |
int i ; | |
int clock [8] ; | |
wiringPiSetup () ; | |
ds1302setup (0, 1, 2) ; | |
if (argc == 2) | |
{ | |
/**/ if (strcmp (argv [1], "-slc") == 0) | |
return setLinuxClock () ; | |
else if (strcmp (argv [1], "-sdsc") == 0) | |
return setDSclock () ; | |
else if (strcmp (argv [1], "-rtest") == 0) | |
return ramTest () ; | |
else | |
{ | |
printf ("Usage: ds1302 [-slc | -sdsc | -rtest]\n") ; | |
return EXIT_FAILURE ; | |
} | |
} | |
for (i = 0 ;; ++i) | |
{ | |
printf ("%5d: ", i) ; | |
ds1302clockRead (clock) ; | |
printf (" %2d:%02d:%02d", | |
bcdToD (clock [2], masks [2]), bcdToD (clock [1], masks [1]), bcdToD (clock [0], masks [0])) ; | |
printf (" %2d/%02d/%04d", | |
bcdToD (clock [3], masks [3]), bcdToD (clock [4], masks [4]), bcdToD (clock [6], masks [6]) + 2000) ; | |
printf ("\n") ; | |
delay (200) ; | |
} | |
return 0 ; | |
} |
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