Lick Adaptive Optics

lgs4 won't boot
Frequent WFS resets
No signal from WFS camera
Loader Errors
Traffic Errors
APD problems


lgs4 downloads its boot file from The boot filename is /u/lgs/Sources.lgs/startup. The most likely sources of lgs4 boot failure are:
  1. lgs4 is not powered on.
  2. lgs4 is not connected to the ethernet.
  3. lgs4 is unable to get its boot file from orthrus.
If lgs4 is not turned on, check that its power cable is plugged into the power strip inside the motor control rack. Make sure the power strip is also turned on.

If lgs4 is on, but still not booting, make sure that the ethernet cable is connected between the motor controller rack e-net hub and the MAU box. Also check that the MAU box is firmly connected to the port on lgs4. Push the reset button on lgs4 to force a reboot.

If this fails, check and make sure the boot file still exists on orthrus. If it doesn't, you will have to retrieve it off an orthrus backup tape.

If all else fails, you can use a terminal emulator program on lgs13 to see what lgs4 is doing at boot time and where the problem may be. Information about connections and the terminal emulator program are on lgs13 (click on the lgs4 (alpha term) README.TXT icon).

  1. Connect DB25 cable from lgs13 port 2 (should already have a DB9-DB25 converter installed in that port) to the lgs4 console port. Depending on which cable is used, you may need a null modem and/or gender changer.
  2. Click on the lgs4 Alpha Serial Console Com2 icon on lgs13.
  3. Push the reset button on lgs4 and watch the boot sequence. It can take up to a minute or two for the boot software to be downloaded and started. If lgs4 boots successfully, you should see a big VXWorks sign displayed, if not, note at which point the boot sequence failed to aid further diagnostics.

Frequent WFS Resets

Often this problem goes away if you power down the camera for 10minutes or more. If this is not sufficient, you can turn off the camera, open it up and check all the power connections. This is a task best left to the AO or telescope operator.

No Signal from WFS Camera

There are a couple sources of this problem. First check that the WFS camera is on. If it is on, check to be sure that the 80 pin grey/red ribbon cable is connected. You may have to restart all the real-time code if it was disconnected. If you still have no signal, you can see if any signal is being generated by disconnecting the 80 pin grey/red ribbon cable and hooking up a monitor to the WFS camera directly using a coax cable. You may have to cycle power on the camera to get active video display. If there is still no video output you will probably have to disassemble the WFS camera to find the (probable) loose or broken power connection. If there is an active video output from the camera, then the problem lies in the real-time computer or the ribbon cable.

Loader Errors

A number of different errors from the real-time control code (loader, testRM, statRMttd) show up in the loader window. Some of these are more serious than others. Example error messages are: CE_ID
temperature -8
Bad control matrix
CE_ID errors are serious and usually occur when VME BUS communications are corrupt or when there is a problem with the Mercury coprocessor board. The first thing to try is stopping all the real-time code and cycling power to lgs6 and lgs3. Restart the software and hope everything works. If that doesn't work, cycle power again and log in as root to lgs6. cd dmc and run a diagnostic program called dmc. If all is well with the mercury card it should be able to run through all its diagnostic tests within 15 minutes or so. If it fails, there is a real problem with the Mercury card and it needs to be sent back for repairs.

temperature -8 (or -7) errors are common and inconsequential. You can ignore these.

Bad control matrix errors happen if for some reason you run out of disk space or create a bad control matrix with the cm command. Just copy and old good control matrix into the new control matrix name to get rid of the error.

Traffic Errors

Traffic is a program that runs on ircalbox that controls all communications between the AO software, IRCAL software, and the telescope. If there are communications problems, make sure that AO is connected to traffic by pushing the PowerUp-Connect to Traffic button. If that fails, make sure traffic is running on ircalbox. Note for some AO software functions (such as moving the telescope) ircalui must be running. You can look at the trafficlog file (on ircalbox in /u/ccdev/ircal/music/logs/) to get more information on what may be the problem.

APD problems

If an APD has anomolously low (overall lack of sensitivity to light) or high counts (high dark current or baseline level) check the following: Words of warning:
The APDs are fragile, treat them with care. They can potentially be damaged by cosmic rays (it does happen to silicon devices). All four APDs are fed by a common power supply. Make sure that the APDs are blocked from all light when powering up. There is a closed loop feedback system inside the APD that holds the temperature of the device, and it takes a minute or so for this to settle. Applying light with the avalanche diode at the wrong temperature is another way to instantly kill it.

Elinor Gates
Last modified: Wed Jun 11 13:04:37 PDT 2003