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    User name Jack

    Log entry time 19:40:42 on October 9,2006

    Entry number 186671

    keyword=Right dipole work from 10-04-06

    Mark and I went down to look at the Right dipole.

    The Dynapower showed 544 amps on the front panel

    Mark connected the laptop to the octagon

    We could type "LIST" and the octagon would spit back the program

    But, we got a response when we typed
    AMPS, Amps, amps, AMP, Amp, or amp.

    When we typed Amps=540 we got no response, but the
    dynapower did not seem to do anything.

    We tried typing Amps=542, Amps=540, and Amps=500
    all to no apparent effect

    We went up under the boxbeam and looked at the VME card.
    The LED for the serial IP was blinking steadily at about
    2 Hz or so.

    We went back down on the platform and connected the laptop
    to the VME side of the serial cable. We saw nothing on the screen.

    I walked over to type in a current setting on the GUI. The
    set current for the magnet was cycling from about 542 amps down
    to 532 amps. I typed a current in between the automatic
    changes. Mark saw nothing on the display.

    I had to leave to use the bathroom.

    Mark typed the commands in to the octagon to ramp the
    dipole current down.

    There was no response from the Dynapower; it stayed at 544 amps.

    I came back and Mark suggested I try setting the current again, but
    with the "regulator" turned off. With the "regulator" turned off
    the cycling of the set current stopped. I entered a current, but
    Mark still saw nothing on the display.

    I occured to me we needed to use a null modem adapter to look at
    the VME side of the serial line.

    Mark went to get an adapter. I went up in the Shield House to
    install some unistrut on the Detector Stack.

    Mark came back and put the null modem adapter on. We still saw
    nothing on the display. I went back over and entered a current
    into the GUI. Mark saw gibberish come up on the display.

    We tried various settings of the COM port, but only saw gibberish
    on the display. 1200, 2400, 9600, 19.2k baud rates at 8 bits,
    XON/XOFF. At 9600b we tried no handshake. We tried even parity.
    we tried 7 bits. We tried 7 bits, 2 stop bits. All gibberish.

    As I write this it occurs to me that after I stopped the
    "regulator" and we had put the null adapter on, we did not go
    under the boxbeam to see it the LED on the IP was still showing
    activity. It may be we saw nothing when we put the null adapter
    on because the VME crate was not trying to talk to the octagon
    anymore, after I had turned off the "regulator".

    At some point, while we were fussing with the baud rates, the
    dynapower started to ramp the current down to zero.

    The magnet current reached zero.

    I felt we had tried enough COM port variations to convince myself
    I needed to get more information on the IP settings.

    We reconneted the VME crate to the octagon.

    We reset the Dynapower, turned it on, and set the momentum. The
    dipole current began ramping up properly.

    Mark and I picked up our toys and left the hall.

    It is unclear to us whether the dipole serial communication was
    interrupted between the IP and the Octagon embedded computer inside the
    Dynapower, or between the Octagon and the Allen Bradley plc inside the
    Dynapower.