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diff --git a/html/parsenew.htm b/html/parsenew.htm deleted file mode 100644 index 0ef60bc06002..000000000000 --- a/html/parsenew.htm +++ /dev/null @@ -1,237 +0,0 @@ -<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML Strict//EN"> -<TITLE>Making PARSE Clocks</TITLE> -<h1>How to build new PARSE clocks</h1> - -<p>Here is an attempt to sketch out what you need to do in order to -add another clock to the parse driver: -Currently the implementation is being cleaned up - so not all information -in here is completely correct. Refer to the included code where in doubt. - - -<p>Prerequisites: -<ul> -<li>Does the system you want the clock connect to have the include files -termio.h or termios.h ? (You need that for the parse driver) -</ul> - - -<p>What to do: - - -<p>Make a conversion module (libparse/clk_*.c) - -<ol> -<li>What ist the time code format ? -<ul> -<li> find year, month, day, hour, minute, second, status (synchronised or -not), possibly time zone information (you need to give the offset to UTC) -You will have to convert the data from a string into a struct clocktime: -<pre> - struct clocktime /* clock time broken up from time code */ - { - long day; - long month; - long year; - long hour; - long minute; - long second; - long usecond; - long utcoffset; /* in seconds */ - time_t utcoffset; /* true utc time instead of date/time */ - long flags; /* current clock status */ - }; -</pre> - -<p>Conversion is usually simple and straight forward. For the flags following -values can be OR'ed together: -<PRE> - PARSEB_ANNOUNCE switch time zone warning (informational only) - PARSEB_POWERUP no synchronisation - clock confused (must set then) - PARSEB_NOSYNC timecode currently not confirmed (must set then) - usually on reception error when there is still a - chance the the generated time is still ok. - - PARSEB_DST DST in effect (informational only) - PARSEB_UTC timecode contains UTC time (informational only) - PARSEB_LEAPADD LEAP addition warning (prior to leap happening - must set when imminent) - also used for time code that do not encode the - direction (as this is currently the default). - PARSEB_LEAPDEL LEAP deletion warning (prior to leap happening - must set when imminent) - PARSEB_ALTERNATE backup transmitter (informational only) - PARSEB_POSITION geographic position available (informational only) - PARSEB_LEAPSECOND actual leap second (this time code is the leap - second - informational only) -</PRE> - -<p>These are feature flags denoting items that are supported by the clock: - <PRE> - PARSEB_S_LEAP supports LEAP - might set PARSEB_LEAP - PARSEB_S_ANTENNA supports ANTENNA - might set PARSEB_ALTERNATE - PARSEB_S_PPS supports PPS time stamping - PARSEB_S_POSITION supports position information (GPS) - </PRE> - - <p>If the utctime field is non zero this value will be take as - time code value. This allows for conversion routines that - already have the utc time value. The utctime field gives the seconds - since Jan 1st 1970, 0:00:00. The useconds field gives the respective - usec value. The fields for date and time (down to second resolution) - will be ignored. - - - <p>Conversion is done in the cvt_* routine in parse/clk_*.c files. look in - them for examples. The basic structure is: - -<PRE> - struct clockformat <yourclock>_format = { - lots of fields for you to fill out (see below) - }; - - static cvt_<yourclock>() - ... - { - if (<I do not recognize my time code>) { - return CVT_NONE; - } else { - if (<conversion into clockformat is ok>) { - <set all necessary flags>; - return CVT_OK; - } else { - return CVT_FAIL|CVT_BADFMT; - } - } -</PRE> - - -<p>The struct clockformat is the interface to the rest of the parse - driver - it holds all information necessary for finding the - clock message and doing the appropriate time stamping. - -<PRE> -struct clockformat -{ - u_long (*input)(); - /* input routine - your routine - cvt_<yourclock> */ - u_long (*convert)(); - /* conversion routine - your routine - cvt_<yourclock> */ - /* routine for handling RS232 sync events (time stamps) - usually sync_simple */ - u_long (*syncpps)(); - /* PPS input routine - usually pps_one */ - void *data; - /* local parameters - any parameters/data/configuration info your conversion - routine might need */ - char *name; - /* clock format name - Name of the time code */ - unsigned short length; - /* maximum length of data packet for your clock format */ - u_long flags; - /* information for the parser what to look for */ -}; -</PRE> - - -<p>The above should have given you some hints on how to build a clk_*.c - file with the time code conversion. See the examples and pick a clock - closest to yours and tweak the code to match your clock. - - - <p>In order to make your clk_*.c file usable a reference to the clockformat - structure must be put into parse_conf.c. -</ul> -<li>TTY setup and initialisation/configuration will be done in -ntpd/refclock_parse.c. -<ul> -<li>Find out the exact tty settings for your clock (baud rate, parity, -stop bits, character size, ...) and note them in terms of -termio*.h c_cflag macros. -<li>in ntpd/refclock_parse.c fill out a new the struct clockinfo element -(that allocates a new "IP" address - see comments) -(see all the other clocks for example) -<PRE> - struct clockinfo - { - u_long cl_flags; /* operation flags (io modes) */ - PARSE_F_PPSPPS use loopfilter PPS code (CIOGETEV) - PARSE_F_PPSONSECOND PPS pulses are on second - usually flags stay 0 as they are used only for special setups - - void (*cl_poll)(); /* active poll routine */ - The routine to call when the clock needs data sent to it in order to - get a time code from the clock (e.g. Trimble clock) - - int (*cl_init)(); /* active poll init routine */ - The routine to call for very special initializations. - - void (*cl_event)(); /* special event handling (e.g. reset clock) */ - What to do, when an event happens - used to re-initialize clocks on timeout. - - void (*cl_end)(); /* active poll end routine */ - The routine to call to undo any special initialisation (free memory/timers) - - void *cl_data; /* local data area for "poll" mechanism */ - local data for polling routines - - u_fp cl_rootdelay; /* rootdelay */ - NTP rootdelay estimate (usually 0) - - u_long cl_basedelay; /* current offset - unsigned l_fp - fractional part (fraction) by - which the RS232 time code is - delayed from the actual time. */ - - u_long cl_ppsdelay; /* current PPS offset - unsigned l_fp fractional - time (fraction) by which the PPS time stamp is delayed (usually 0) - part */ - - char *cl_id; /* ID code (usually "DCF") */ - Refclock id - (max 4 chars) - - char *cl_description; /* device name */ - Name of this device. - - char *cl_format; /* fixed format */ - If the data format cann not ne detected automatically this is the name - as in clk_*.c clockformat. - - u_char cl_type; /* clock type (ntp control) */ - Type if clock as in clock status word (ntp control messages) - usually 0 - - u_long cl_maxunsync; /* time to trust oscillator after loosing synch - */ - seconds a clock can be trusted after loosing synchronisation. - - u_long cl_speed; /* terminal input & output baudrate */ - u_long cl_cflag; /* terminal io flags */ - u_long cl_iflag; /* terminal io flags */ - u_long cl_oflag; /* terminal io flags */ - u_long cl_lflag; /* terminal io flags */ - termio*.h tty modes. - - u_long cl_samples; /* samples for median filter */ - u_long cl_keep; /* samples for median filter to keep */ - median filter parameters - smoothing and rejection of bad samples - } clockinfo[] = { - ...,<other clocks>,... - { < your parameters> }, - }; - -</PRE> -</ul> -</ol> - -<p>Well, this is very sketchy, i know. But I hope it helps a little bit. -The best way is to look which clock comes closest to your and tweak that -code. - -<p>Two sorts of clocks are used with parse. Clocks that automatically send -their time code (once a second) do not need entries in the poll routines because -they send the data all the time. The second sort are the clocks that need a -command sent to them in order to reply with a time code (like the Trimble -clock). - -<p>For questions: <a href="mailto: kardel@acm.org">kardel@acm.org</a>. - -<p>Please include an exact description on how your clock works. (initialisation, -TTY modes, strings to be sent to it, responses received from the clock). -<hr><p> -<a href="http://www4.informatik.uni-erlangen.de/~kardel">Frank Kardel</a> |