DEIMOS
Lantronix Reset Procedure

Background

The Lantronix terminal server is a device which coordinates communication among the various controllers in DEIMOS. The first indication of a problem with the Lantronix terminal server on DEIMOS might be problems commanding motors. Other symptoms may exist as well but this problem can be confirmed by running testAll on polo. If the Lantronix unit is unresponsive, the return from this command will indicate a problem communicating to the Lantronix (IP 192.168.6.4).

Procedure

Follow these steps to cycle power to the Lantronix terminal server:
  1. Rotate DEIMOS to access electronics bay 3. The electronics bays are located around the large ring-like structure at the back of the instrument. They are labeled with numbers and contents. There are three ways to set the instrument rotator position:
    • Have the observer rotate DEIMOS to an angle of 0° or 180° from the DEIMOS rotation subpanel.
    • Have the OA rotate DEIMOS to physical drive angle 90° or -90°.
    • Alteratively, you can rotate by putting the DEIMOS hand paddle in manual mode, turning the mode selector to 0 (fast jog), then using the FWD or REV buttons to turn the instrument until you can access bay 3.
    These put the bay on the left and right hand sides of the instrument, respectively, when viewed from the rear of the instrument looking toward the telescope.
  2. Safety first: before removing a cover, put the band brake on! See figure 1.
  3. To access the Lantronix power switch, remove the cover shown in figure 2. Please note the following:
    • You only need a flat-blade screwdriver. All fasteners are 1/4 turn captured.
    • A suitable flat-blade is available right by the DEIMOS hand paddle.
    • Do not undo the allen bolts visible on the panel.
    • This panel "wraps around the instrument". In other words it will be sort of L-shaped when removed.
  4. Figure 3 shows the Lantronix terminal server and the rocker power switch.
  5. Getting the cover back on can be a little tricky. Seat all the 1/4 turn fasterners in their sockets first then go around turning them.
  6. Don't forget when leaving: release the band brake, set hand paddle in computer mode.

Figure 1. DEIMOS band brake

Image showing DEIMOS band brake

Band brake. Push lever down to engage. Pull up to release.

Figure 2. DEIMOS electronics bay 3

Image showing DEIMOS electronics bay 3

Panel to be removed. Only undo the flat blade 1/4 turn quick release fasteners. Do not try to undo the allen screws that are visible in the panel.

Figure 3. DEIMOS Lantronix terminal server

Image showing DEIMOS Lantronix terminal server

Lantronix terminal server in electronics bay 3.

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Last modified: Thu Jul 17 11:41:48 HST 2008