Re: [ntp:questions] how to write a reference clock driver

Harlan Stenn wrote: In article 4944eab4$0$12693$9b622...@news.freenet.de, Juergen Kosel juergen.ko...@freenet.de writes: Juergen Hello, Greg Dowd schrieb: I'm not quite sure what you mean. A reference clock doesn't compute an offset, it acquires, formats and returns a time value from an

Re: [ntp:questions] how to write a reference clock driver

Hello, Harlan Stenn schrieb: In article 4948f81b$0$29004$9b622...@news.freenet.de, Juergen Kosel juergen.ko...@freenet.de writes: And I also don't understand what you mean by computing time is a concern. Is the overhead of a subroutine call that significant in your application? it would

Re: [ntp:questions] how to write a reference clock driver

Juergen Kosel juergen.ko...@freenet.de writes: Hello, Harlan Stenn schrieb: In article 4948f81b$0$29004$9b622...@news.freenet.de, Juergen Kosel juergen.ko...@freenet.de writes: And I also don't understand what you mean by computing time is a concern. Is the overhead of a subroutine call

Re: [ntp:questions] how to write a reference clock driver

Hello, Harlan Stenn schrieb: In article 4944eab4$0$12693$9b622...@news.freenet.de, Juergen Kosel juergen.ko...@freenet.de writes: Juergen Hello, Greg Dowd schrieb: I'm not quite sure what you mean. A reference clock doesn't compute an offset, it acquires, formats and returns a time value

Re: [ntp:questions] how to write a reference clock driver

In article 4948f81b$0$29004$9b622...@news.freenet.de, Juergen Kosel juergen.ko...@freenet.de writes: Juergen Those driver give the time in the format month, day, hour, Juergen minute,... Function refclock_process() converts this time into Juergen seconds and nanosecond. But my reference clock

Re: [ntp:questions] how to write a reference clock driver

In article 4944eab4$0$12693$9b622...@news.freenet.de, Juergen Kosel juergen.ko...@freenet.de writes: Juergen Hello, Greg Dowd schrieb: I'm not quite sure what you mean. A reference clock doesn't compute an offset, it acquires, formats and returns a time value from an external source. NTP

Re: [ntp:questions] how to write a reference clock driver

They take the time from the reflock along with the system timestamp (with the intent to get the system timestamp as close as possible to the moment the refclock timestamp is obtained), build the contents of the struct refclockproc, and call refclock_process(). I think it's slightly more

Re: [ntp:questions] how to write a reference clock driver

Hello, Greg Dowd schrieb: I'm not quite sure what you mean. A reference clock doesn't compute an offset, it acquires, formats and returns a time value from an external source. NTP takes care of the rest. ntpd reads the time of a reference clock with a reference clock driver. My problem was,

[ntp:questions] how to write a reference clock driver

Hello, I have a system with hardware support for PTP (IEEE 1588 time synchronisation) [ http://en.wikipedia.org/wiki/Precision_Time_Protocol ]. So the system can read from two 32 bit registers seconds and nanoseconds since 1.1.1970. It appears like the system time, but is n't the system time. To

Re: [ntp:questions] how to write a reference clock driver

+gdowd=symmetricom@lists.ntp.org] On Behalf Of Juergen Kosel Sent: Thursday, December 11, 2008 10:53 AM To: questions@lists.ntp.org Subject: [ntp:questions] how to write a reference clock driver Hello, I have a system with hardware support for PTP (IEEE 1588 time synchronisation) [ http

Re: [ntp:questions] how to write a reference clock driver

I have already read http://www.eecis.udel.edu/~mills/ntp/html/howto.html and started with a copy of refclock_local.c. But from the documentation it is not clear, in what way the offset should be calculated and used. E.g.: offset = ref_clock_time - system_time; or offset = system_time -

Re: [ntp:questions] how to write a reference clock driver

Juergen Kosel juergen.ko...@freenet.de writes: Hello, I have a system with hardware support for PTP (IEEE 1588 time synchronisation) [ http://en.wikipedia.org/wiki/Precision_Time_Protocol ]. So the system can read from two 32 bit registers seconds and nanoseconds since 1.1.1970. It appears like