arch/i386-pc/battclock/readbattclock.c

   1 /*
   2     Copyright © 1995-2001, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Desc: ReadBattClock() function.
   6     Lang: english
   7 */
   8 #include "battclock_intern.h"
   9
  10 #define CENTURY         0x32
  11 #define YEAR            0x09
  12 #define MONTH           0x08
  13 #define MDAY            0x07
  14 #define HOUR            0x04
  15 #define MIN             0x02
  16 #define SEC             0x00
  17 #define STATUS_A        0x0A
  18 #define STATUS_B        0x0B
  19 #define HEALTH          0x0E
  20
  21 inline unsigned char read_port(unsigned char port);
  22 inline int bcd_to_dec(int x);
  23
  24 /*****************************************************************************
  25
  26     NAME */
  27 #include <proto/battclock.h>
  28 #include <proto/utility.h>
  29 #include <utility/date.h>
  30
  31         AROS_LH0(ULONG, ReadBattClock,
  32
  33 /*  SYNOPSIS */
  34         /* void */
  35
  36 /*  LOCATION */
  37         struct BattClockBase *, BattClockBase, 2, Battclock)
  38
  39 /*  FUNCTION
  40         Return the value stored in the battery back up clock. This value
  41         is the number of seconds that have elapsed since midnight on the
  42         1st of January 1978 (00:00:00 1.1.1978).
  43
  44         If the value of the battery clock is invalid, then the clock will
  45         be reset.
  46
  47     INPUTS
  48
  49     RESULT
  50         The number of seconds since 1.1.1978 00:00:00
  51
  52     NOTES
  53
  54     EXAMPLE
  55
  56     BUGS
  57
  58     SEE ALSO
  59         WriteBattClock, ResetBattClock
  60
  61     INTERNALS
  62
  63     HISTORY
  64         27-11-96    digulla automatically created from
  65                             battclock_lib.fd and clib/battclock_protos.h
  66
  67 *****************************************************************************/
  68 {
  69     AROS_LIBFUNC_INIT
  70
  71     struct ClockData date;
  72     UWORD century;
  73     UWORD status_b;
  74     ULONG  secs;
  75
  76     date.sec   = read_port(SEC);
  77     date.min   = read_port(MIN);
  78     date.hour  = read_port(HOUR);
  79     date.mday  = read_port(MDAY);
  80     date.month = read_port(MONTH);
  81     date.year  = read_port(YEAR);
  82     century    = read_port(CENTURY);
  83     status_b   = read_port(STATUS_B);
  84
  85     if ((status_b & 0x04) == 0) {
  86         date.sec   = bcd_to_dec(date.sec);
  87         date.min   = bcd_to_dec(date.min);
  88         date.hour  = bcd_to_dec(date.hour);
  89         date.mday  = bcd_to_dec(date.mday);
  90         date.month = bcd_to_dec(date.month);
  91         date.year  = bcd_to_dec(date.year);
  92         century    = bcd_to_dec(century);
  93     }
  94
  95     date.year = century * 100 + date.year;
  96
  97     secs=Date2Amiga(&date);
  98
  99     return secs;
 100
 101     AROS_LIBFUNC_EXIT
 102 } /* ReadBattClock */
 103
 104 /* help functions */
 105 unsigned char read_port(unsigned char port)
 106 {
 107     unsigned char tmp;
 108
 109     asm volatile (
 110     "outb       %1,$0x70        \n\t"           \
 111     "inb        $0x71,%0"                       \
 112     : "=a"(tmp)                         \
 113     : "a"(port));
 114
 115     return tmp;
 116 }
 117
 118 inline int bcd_to_dec(int x)
 119 {
 120     return ( (x >> 4) * 10 + (x & 0x0f) );
 121 }