last update: 050131

Checking Trigger Hardware

To check the states of the CPUs use the command chkstates.

Checking or Setting Central Trigger Barrel high voltage

Type trghv and wait for the display (~1 min). The CTB uses 16 separate LeCroy 1440 HV pods, 15 channels each. The ZDC uses the last channel in the 1st 3 pods and in the last 3 pods. The default settings for HV are in :

/star/sc/users/sysuser/epics/R3.12.2-LBL.4/TRGhvApp/src/demand

Once you have the trghv program running, you can turn the voltage on or off with the global command in the upper (HV ON/OFF) right hand corner of the page. To see individual PMT HV values, click on a slot page at the bottom of the panel. For instance to see the first 16 channels of HV, hit "slot0" at the bottom of the panel.

If you have a problem with the voltages coming up to their set points, indicated by red circles on one or more of the channels on one or more of the slot pages (except slot 9,10,11,12 whose last channel SHOULD be 0) then you can hit the "ZERO" button on the main panel, and then, after 30 seconds, hit the RETREIVE button. This should eliminate any red circles for real PMT channels. You should then check each slot page to make sure there are no re dots. If a red dot persists, you need to use the setting bar to zero the channel, then wait 15 sec, then set the correct value in the numerical value box and hope the channel achieves its setpoint. I have had to repeat this procedure 2 or 3 times to get some of the channels to respond.

Checking VME crate status

Type tpc_top. Hit the button in the lower right for VME status. ll trigger crates should be on. If not, you have to turn them all on and then restart the trigger system.

To cycle power on the trigger crates, check cycling power.

Then check the processors to see whether they have booted correctly. If a processor reports an error, try a ctrl-x in its control window to reboot.

Checking trigger processor states

As STARTPC, use the command grab_all to establish windows for all of the trigger cpus. In each window, you can hit return and shoud get the cpu_name> prompt, eg, l1ctl_full>, where the full means it has been booted with the full configuration.

Checking connections to RHIC