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    User name kramerk

    Log entry time 06:59:22 on July27,2001

    Entry number 67929

    keyword=DAQ problems solved finally

    So here's a summary of the problem and solution:
    1) Discriminator Thresholds were set to zero when we began running this evening because of various IOC problems. We didn't notice this until we began seeing 50+% deadtime in both arms and noticed event size was huge (files split very quickly).
    2) We stopped the runs and reset the threshholds to 4.0 V as they were set before.
    3) Right arm dead time was now okay. Left Arm stuck at 100%. Using espace, Xiaochao noticed left arm scintillator ADCs were zero, but everything else was okay. T1 and T3 rates normal and prescales set correctly. Killed Coda and rebooted all crates twice to no avail.
    4) Paged Bob. Bob told me to check ROC2 rates. Rates were zero. Bob's theory was that the crates were stuck in busy mode, then suggested I make an access and cycle the power on the Trigger Supervisor. If that didn't work then cycle the power on the Fastbus crate.
    5) I made an access to the left arm spectrometer hut. I cycled the power on the trigger supervisor. I then called the counting house and had Lisa start and stop a run. When Lisa saw the TS1 component was back. She reset the left arm runcontrol and started a run on all the DAQs. The left arm still showed 100% deadtime.
    6) I then cycled the power on the Fastbus crate. After waiting a while we were unable to telnet to ROC2. I cycled the power again and still had the same problem.
    7) Paged Bob again. Bob reset the memory on ROC2. We started a new run with no beam and the left arm deadtime was 3% from cosmics. Problem fixed!
    8) Called MCC to put the hall back in Beam Permit.