hetetimecode.h

Go to the documentation of this file.

/*
 *  $Id: hetetimecode.h 80 2007-05-11 16:10:54Z gbc $
 *
 *  HETE clock globals.
 *
 *  Copyright (C) 1998 by MIT.          All rights reserved.
 */
 
#ifndef _HETETIMECODE_H
#define _HETETIMECODE_H
 
typedef unsigned short IPP_word;
 
typedef struct
{
    IPP_word    time[4];    
}   time_code;
 
/* Words are in little-endian order: 
 *  time[0] is microseconds.
 *  time[1] units are about 66 ms.
 *  time[2] units are about 1.2 hours
 *  time[3] units are about 9 years.
 *
 * time[3] codes the "epoch" of the time. On the spacecraft, the epoch
 * is determined by the digital watch's jumpers. In other environments,
 * it depends on the clock source:
 */
 
#define EPOCH_NULL  0   /* no clock available */
#define EPOCH_UNSYNC    0x1 /* raw unsynchronized processor time */
#define EPOCH_HUBSYNC   0x2 /* HUB synchronized time, no watch */
#define EPOCH_WATCH(N)  (0x10|(N))  /* synchronized to watch 0<=N<=15 */
#define EPOCH_UNIX(N)   (0x20|(N))  /* Unix sys time, N is 4 MSB's */
 
/* note that HETE-II started in EPOCH_UNIX(3). EPOCH_UNIX(4) will begin
 * January 10, 2004 at 13:37:04 UT
 */
 
/*
 *  Epoch 003X will be used for IBEX.
 */
#define THIS_IS_IBEX    ((Ht_hete_epoch & 0x30) == 0x30)
#define EPOCH_IBEX(N)   (0x30|(N))
 
/* The HETE-I interface: returns microseconds as an unsigned as well as the
 * code. The pointer may be null if you don't want the code.
 */
 
extern unsigned get_sc_time(time_code *tc);
 
/* A slightly lower level interface, for your convenience in constructing
 * messages as arrays:
 */
 
extern void get_sc_time_array(IPP_word time[4]);
 
/* Ordering functions */
extern int time_cmp(time_code *time1, time_code *time2);
extern int has_this_time_passed(time_code *time);
 
#endif /* _HETETIMECODE_H */
 
/*
 * eof
 */