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diff --git a/contrib/ntp/html/driver28.htm b/contrib/ntp/html/driver28.htm deleted file mode 100644 index 787ccb4..0000000 --- a/contrib/ntp/html/driver28.htm +++ /dev/null @@ -1,133 +0,0 @@ -<HTML> -<HEAD> - <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> - <META NAME="GENERATOR" CONTENT="Mozilla/4.01 [en] (Win95; I) [Netscape]"> - <TITLE>Shared memoy Driver -</TITLE> -</HEAD> -<BODY> - -<H3> -Shared Memory Driver</H3> - -<HR> -<H4> -Synopsis</H4> -Address: 127.127.28.<I>u</I> -<BR>Reference ID: <TT>SHM</TT> -<BR>Driver ID: <TT>SHM</TT> -<H4> -Description</H4> -This driver receives its reference clock info from a shared memory-segment. -The shared memory-segment is created with owner-only access for unit 0 -and 1, and world access for unit 2 and 3 -<H4> -Structure of shared memory-segment</H4> - -<PRE>struct shmTime { - int mode; /* 0 - if valid set - * use values, - * clear valid - * 1 - if valid set - * if count before and after read of - * values is equal, - * use values - * clear valid - */ - int count; - time_t clockTimeStampSec; /* external clock */ - int clockTimeStampUSec; /* external clock */ - time_t receiveTimeStampSec; /* internal clock, when external value was received */ - int receiveTimeStampUSec; /* internal clock, when external value was received */ - int leap; - int precision; - int nsamples; - int valid; - int dummy[10]; -};</PRE> - -<H4> -Operation mode=0</H4> -When the poll-method of the driver is called, the valid-flag of the shared -memory-segment is checked: - -<P>If set, the values in the record (clockTimeStampSec, clockTimeStampUSec, -receiveTimeStampSec, receiveTimeStampUSec, leap, precision) are passed -to ntp, and the valid-flag is cleared. - -<P>If not set, a timeout is reported to ntp, nothing else happend -<H4> -Operation mode=1</H4> -When the poll-method of the driver is called, the valid-flag of the shared -memory-segment is checked: - -<P>If set, the count-field of the record is remembered, and the values -in the record (clockTimeStampSec, clockTimeStampUSec, receiveTimeStampSec, -receiveTimeStampUSec, leap, precision) are read. Then, the remembered count -is compared to the count now in the record. If both are equal, the values -read from the record are passed to ntp. If they differ, another process -has modified the record while it was read out (was not able to produce -this case), and failure is reported to ntp. The valid flag is cleared. - -<P>If not set, a timeout is reported to ntp, nothing else happend -<H4> -Fudge Factors</H4> - -<DL> -<DT> -<TT>time1 <I>time</I></TT></DT> - -<DD> -Specifies the time offset calibration factor, in seconds and fraction, -with default 0.0.</DD> - -<DT> -<TT>time2 <I>time</I></TT></DT> - -<DD> -Not used by this driver.</DD> - -<DT> -<TT>stratum <I>number</I></TT></DT> - -<DD> -Specifies the driver stratum, in decimal from 0 to 15, with default 0.</DD> - -<DT> -<TT>refid <I>string</I></TT></DT> - -<DD> -Specifies the driver reference identifier, an ASCII string from one to -four characters, with default <TT>SHM</TT>.</DD> - -<DT> -<TT>flag1 0 | 1</TT></DT> - -<DD> -Not used by this driver.</DD> - -<DT> -<TT>flag2 0 | 1</TT></DT> - -<DD> -Not used by this driver.</DD> - -<DT> -<TT>flag3 0 | 1</TT></DT> - -<DD> -Not used by this driver.</DD> - -<DT> -<TT>flag4 0 | 1</TT></DT> - -<DD> -Not used by this driver.</DD> - - -<P>Additional Information - -<P><A HREF="refclock.htm">Reference Clock Drivers</A></DL> - -</BODY> -</HTML> |
