/************************************************************************/ /* Copyright 1990 - 1997 MBARI */ /************************************************************************/ /* $Header: rtc.c,v 1.2 91/09/23 09:38:59 hebo Exp $ */ /* Summary : Functions to read time from MK48T08 chip on MVME-162 CPU */ /* under vxWorks */ /* Filename : rtc.c */ /* Author : Bob Herlien (rah) */ /* Project : Tiburon ROV */ /* $Revision: 1.2 $ */ /* Created : 02/28/91 */ /************************************************************************/ /* Modification History: */ /* $Log: rtc.c,v $ * Revision 1.2 91/09/23 09:38:59 09:38:59 hebo (Bob Herlien 408-647-3748) * Minor bug fixes, added -DMICROTIME * * Revision 1.1 91/09/06 16:05:35 16:05:35 hebo (Bob Herlien 408-647-3748) * Initial revision * * Revision 1.0 91/08/09 11:10:33 11:10:33 hebo (Bob Herlien 408-647-3748) * Initial revision * */ /* 28feb91 rah, created */ /************************************************************************/ /* The Unix Epoch (day 0) is Jan 1, 1970. The real-time clock chip */ /* only gives 2 decimal digits of year. Also, a Unix time_t value */ /* (signed long) can only go +/- 68 years from 1970. Therefore, these */ /* routines assume that the year is between 1970 and 2070. Note that */ /* the leap-year exception for centuries not divisible by 400 is not a */ /* factor in this period. */ /************************************************************************/ #include /* MBARI standard types */ #include /* VxWorks includes */ #include /* struct tm definition */ #include /* struct timeval, timezone defns */ #include /* time structure definitions */ #include "mv162.h" /* Hardware defns for MVME-162 */ /* Defines for MK48T08 Real-Time Clock Chip on MVME-162 */ #define RTC(x) ((unsigned char *)(TOD_CLOCK + x)) #define RTC_CTRL RTC(0) /* Control byte of RTC chip */ #define RTC_SECS RTC(1) /* Seconds on RTC chip */ #define RTC_MINS RTC(2) /* Minutes on RTC chip */ #define RTC_HR RTC(3) /* Hours on RTC chip */ #define RTC_DAY RTC(4) /* Day of week (1 - 7) on RTC chip */ #define RTC_DATE RTC(5) /* Date (1 - 31) on RTC chip */ #define RTC_MONTH RTC(6) /* Month on RTC chip */ #define RTC_YR RTC(7) /* Year (00 - 99) on RTC chip */ #define STOP_BIT 0x80 /* "Stop Clock" bit in seconds field*/ #define WRITE_BIT 0x80 /* "Write" bit in control byte */ #define READ_BIT 0x40 /* "Read" bit in control byte */ /********************************/ /* External Functions */ /********************************/ Extern Int32 julday( Int32 yr, Int32 mo, Int32 day ); Extern Int32 ep_days( Int32 year, Int32 yday ); /************************************************************************/ /* Function : bcd_to_hex */ /* Purpose : BCD to hex conversion */ /* Input : BCD byte */ /* Outputs : Hex byte */ /************************************************************************/ Int32 bcd_to_hex( Int32 byte ) { return( (10 * (byte>>4)) + (byte & 0xf) ); } /* bcd_to_hex() */ /************************************************************************/ /* Function : hex_to_bcd */ /* Purpose : Hex to BCD conversion */ /* Input : Hex byte */ /* Outputs : BCD byte */ /************************************************************************/ Int32 hex_to_bcd( Int32 byte ) { return( ((byte / 10) << 4) + (byte % 10) ); } /* hex_to_bcd() */ /************************************************************************/ /* function : rtc_on */ /* purpose : Make sure rtc chip is running */ /* inputs : None */ /* outputs : None */ /************************************************************************/ Void rtc_on( Void ) { if ( *RTC_SECS & STOP_BIT ) /* Clock stopped? */ *RTC_SECS &= ~STOP_BIT; /* Start it */ } /* rtc_on() */ /************************************************************************/ /* Function : sysRtcRead */ /* Purpose : Read the RTC chip, put the results in struct tm *tp */ /* Inputs : Pointer to struct tm to put current time into */ /* Outputs : Time in time_t format */ /************************************************************************/ time_t sysRtcRead( struct tm *tp ) { time_t rtn; struct tm temp_tm; rtc_on(); /* Make sure RTC is running */ if ( tp == (struct tm *)NULL ) /* If no tm, use temp one */ tp = &temp_tm; *RTC_CTRL |= READ_BIT; /* Stop updating clock */ tp->tm_sec = bcd_to_hex(*RTC_SECS & 0x7f); tp->tm_min = bcd_to_hex(*RTC_MINS & 0x7f); tp->tm_hour = bcd_to_hex(*RTC_HR & 0x3f); tp->tm_mday = bcd_to_hex(*RTC_DATE & 0x3f); tp->tm_mon = bcd_to_hex(*RTC_MONTH & 0x1f) - 1; tp->tm_year = bcd_to_hex(*RTC_YR); if ( tp->tm_year < YEAR0 ) /* RTC_YR 00 is actual year 2000*/ tp->tm_year += 100; tp->tm_wday = (*RTC_DAY & 7) - 1; *RTC_CTRL &= ~(WRITE_BIT | READ_BIT); /* Restart clock updating */ tp->tm_yday = julday( (tp->tm_year % 100), tp->tm_mon, tp->tm_mday ) - 1; tp->tm_isdst = 0; rtn = ep_days(tp->tm_year - YEAR0, tp->tm_yday) * SECS_PER_DAY; rtn += (tp->tm_hour * 3600L) + (tp->tm_min * 60) + tp->tm_sec; return( rtn ); } /* sysRtcRead() */ /************************************************************************/ /* Function : sysRtcWrite */ /* Purpose : Write the RTC chip from the values of struct tm *tp */ /* Inputs : Pointer to struct tm that contains current time */ /* Outputs : None */ /************************************************************************/ Void sysRtcWrite( const struct tm *tp ) { rtc_on(); /* Make sure RTC is running */ *RTC_CTRL |= WRITE_BIT; /* Stop the clock */ *RTC_SECS = (char)(hex_to_bcd(tp->tm_sec) & 0x7f); *RTC_MINS = (char)(hex_to_bcd(tp->tm_min) & 0x7f); *RTC_HR = (char)(hex_to_bcd(tp->tm_hour) & 0x3f); *RTC_DAY = (char)((tp->tm_wday + 1) & 7); *RTC_DATE = (char)(hex_to_bcd(tp->tm_mday) & 0x3f); *RTC_MONTH = (char)(hex_to_bcd(tp->tm_mon + 1) & 0x1f); *RTC_YR = (char)hex_to_bcd(tp->tm_year % 100); *RTC_CTRL &= ~(WRITE_BIT | READ_BIT); /* Restart clock */ } /* sysRtcWrite() */