FS clock errors

If the FS is complaining frequency of a formatter to FS time difference > 0.5s, it may be necessary to recalibrate the drift rate. The procedure is outlined in /usr2/fs/misc/fstime.txt. The guts of the procedure is:

- Ordered List Item Make sure there is a “sy=run setcl &” in the “initi” procedure of the “station” procedure library. It should go as early as possible in the procedure. - Ordered List Item Make sure there is a “sy=run setcl adapt &” in the “midob” procedure in “station”. - Ordered List Item Set-up the “time.ctl” file with the following steps. Please note that this procedure should be repeated whenever you change FS computers or upgrade kernels. Another case where you should redo this step is if the crystal has either because of aging or other reasons, like replacement, changed significantly in rate.

• Unordered List Item Put the following line in your “time.ctl” file as the only non-comment line:
  0.000 0.010 rate
• Unordered List Item Start the FS
• Unordered List Item Execute the SNAP command: “sy=run setcl offset &”
• Unordered List Item Leave the computer running for about one hour. You can start and stop the FS, login and logout as many times as you wish. Just don't reboot the computer.
• Unordered List Item Execute the SNAP command: “sy=run setcl rate &”
• Unordered List Item Execute the SNAP command: “sy=run setcl save &”
• Unordered List Item . At a shell prompt execute:
  
  cd /usr2/control
  mv time.new time.ctl
  As long as there were no communication or permission errors, your “time.ctl” file should be updated with a reasonable rate value.