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:

1. 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.
2. Make sure there is a “sy=run setcl adapt &” in the “midob” procedure in “station”.
3. 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.

• Put the following line in your “time.ctl” file as the only non-comment line:
  0.000 0.010 rate
• Start the FS
• Execute the SNAP command: “sy=run setcl offset &”
• 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.
• Execute the SNAP command: “sy=run setcl rate &”
• Execute the SNAP command: “sy=run setcl save &”
• 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.