TCS Acting Up... with numerous seemingly unrelated problems in tracking and commanding.
Dome Auto Acting up... with failure to pre-position or failure to follow telescope.
IRAF interface failure... when getting header information from the TCS or commanding it to 'nod'.

TCS ACTING UP (return to top)

• TCS not accepting commands
• TCS not going where commanded
• TCS not responsive

Restart TCS Monitor
• Select 'Special' Pull down Menu.
• Choose: Restart TCS Monitor and confirm by clicking OK.

NOTE: The 'mcd107x' interface of IRAF will fail after reboot.   You will have to exit IRAF and restart it when tcsmon comes back up if you are getting header information from, or sending 'nod' commands to the telescope.

TCS Still Acting up...
Select 'Reboot TCS' on the 'Special' pull down menu

TCS Still Acting up...
Restart the PMAC code as follows:
• Log into colossus from and xterm window or from the console.
• Run the pmac executive program: pe 1

(that is 'pe' and the number one) and issue: $$$
followed a carriage return <cr> and then  ^D to exit.

NOTE:  After this step, you MUST restart tcsmon following 2.a.1 above.

WARNING: Exit this xterm window when done or you may inadvertently reprogram the Motion Control Card.  This could result in loss of the telescope or loss of lifeWE ARE NOT JOKING.

TCS STILL Acting up...
If none of this works or colossus is hung to the extent that you cannot execute these commands, it is time to Power cycle the TCS.  This should be a last resort, since the first step of a power cycle usually works (power off), but the next step (power on) is sometimes too much for the computer and may require help from the staff.  A power cycle requires ~10 minutes to rebuild its disk, and the rebuild is often followed by subsequent reboots.  If the computer auto-reboots more than 3 times, or it just hangs, call for help.

The power switch is located on the black computer above eye level in the old control room over the small TCS monitor.  It is a toggle to your left.

DOMEAUTO ACTING UP (return to top)

i. Toggle TCS Enable OFF, then ON
Select Enable Dome Automation from the TCS Tools pull down menu
After 15 seconds, Enable Dome Automation should be tagged with a red dot indicating ON. The Dome Az display on the right should indicate "(AUTO)" and turn
green indicating ON.

ii. No Luck...
Cycle Telescope/Dome power with the E-stop button. Then restart the TCS from the "Special" menu. (but see item
iv below first!).

iii. Dome Auto Still acting up...
Power cycle guardian. Then try to enable DomeAuto from the TCS.

iv. Dome Auto Still acting up...
(or you just want to finish an integration w/out stopping tracking.)
Start 'dumb' mode tracking by logging into

Use username: enable and the password posted on the dome auto computer in the old control room.  If you use this mode of operation, you can disable domeauto by logging in with username: disable (same password) and park by logging in with username park (same password).

IRAF gets a read error when polling the tcs for information for header files or IRAF gets a read error when trying to 'nod' the telescope with a script such as SKYSUB.

ic> telescope
ERROR: Write to IPC with no reader

This indicates that the socket connection between IRAF and the TCS (mcd107x) has been broken.  This occurs when the TCS Monitor is re-started.

i. Restart IRAF and ICEX
The only complete fix is to exit IRAF and re-start.  After re-start, try the 'telescope' command before you spend any time setting up your instrument to make sure that the 'mcd107x' interface is going to work.

ii. Avoid Re-starting by IRAF by Using the Old Encoders and Telescope Interface
If you are only using the 'mcd107x' interface for header information, and you do not want to loose the time involved in re-starting IRAF, you can opt to use the old 'mcd107' interface by selecting it in telpars.  This will NOT work if you are nodding the telescope.  Further, you must accept that the pointing information in your header will now rely on a faulty encoder.


PMAC DP-RAM  Display

1. From colossus type: tcs_mem_read.exe

NOTE:  If TCSMON is NOT running, type: tcs_mem_read.exe   r
NOTE:  Information is not updated if Maint Mode switch is ON

2. Check that Servo cnt (2258.8 Hz) is incrementing, and that TCS Alive=1

3. PMAC Report (lines beginning with 1/2) displays current PMAC status

• Mode=1 if TCS is running
• Tracking 1=on, 0=off
• Jogging 1=telescope is moving (slew,srch,set,guide, or dig modes)
• Cmd Slave, Act and Master show incremental encoder positions in mas
• Velocity is in mas/sec
• Servo Capture will change when encoder slips
• DAC shows driving voltage (millivolts) sent to power amps
• Current shows driving current from PowerAmps (milliAmp) 6A Max

4. PMAC Request (lines beginning with 3/4) display commands to PMAC

• Tracking Rate shows current rate in mas
• Position shows Autoslew position (compare to Cmd Slave line in Report)   or digital step size in mas
• Jog rate displays last motion rate in mas/sec

5. Handpaddle Inputs show button positions

• "T" or "-" under N and E buttons indicate whether Tracking switches are ON or OFF

6. PMAC Outputs

• Note values of E-stop and Focus

7. PMAC Signal Inputs

• PPrA and DPrA are Polar and Dec Power Amps
• DdMan is the Auto-Slew button position
• Mnt shows the position of the Maint mode switch.
• Hyd shows whether there is hydraulic pressure on the Polar Axis
• 28v is the status of the Reset button on the dome console.  1=reset was pushed

NOTE: some signals will not appear if 28v = 0

8. Limit Switch Inputs

• EP and WP show if East ant West platforms are down.  1=down

Domeauto Display

1. log into guardian;  use username: monitor password posted on the domeauto computer.
2. verify that domeauto is receiving current times/coordinates from colossus
3. verify proper MODE  (disabled or enabled)
4. verify current DOME position and TARGET position
5. verify current PREPOSITION COORDs (match TCS "Go Next")
6. If above is OK but dome doesn't function, call Ward, Green, Blackley.

If something is NOT correct above, call Ward, Spiesman, Ricklefs


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21 March 2002
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