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<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">Hello,</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">In Linux PPS documentation it is said:</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">PPS means "pulse per second" and a PPS source is just a device which</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">provides a high precision signal each second so that an application</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">can use it to adjust system clock time.</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">But I haven't find out how to do this adjusting of system clock timer</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">(hwclock).</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
The requirement of pps in my system: the 1pps comes from GPIO and should be used for timetag of video captured frames from camers. <span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);"> I
rather not using ntp, and instead find a simpler way to achieve it, so that there is no overhead of ntp</span><span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">.</span></div>
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<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">1. Is that possible to adjust system timer from PPS (without ntp) ? Is there an example showing how to do it ?</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="background-color: rgb(255, 255, 255);"><font color="#222222" face="Arial, Helvetica, sans-serif" size="2">2. Is it that the time_pps_kcbind API is responsible to adjust system clock</font></span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">with PPS ? Is there an example showing how to do it ?</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">I also don't fully understand the pps time interface,as can be read from</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">userspace using time_pps_fetch command (see ppstest.c example)</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">3. How is it that pps already have nsec resolution if it is a clock</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">which is only "pulse per second" ? Does it mean that the</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">time_pps_fetch already gives time which is synchronized with system</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">timer ?</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
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<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">Thank you!</span><br style="color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">
<span style="font-family: Arial, Helvetica, sans-serif; font-size: small; color: rgb(34, 34, 34); background-color: rgb(255, 255, 255);">ran</span>
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