From: Jack Lebowitz <Jack_Lebowitz@micro.microbio.uab.edu>
  To  : rasmb@bbri.org
  Date: Thu, 21 Jan 1999 14:45:08 -0600

Help wanted with a serious XL-A data communication failure

Dear RASMBers

We have a serious XL-A problem, that I will relate below, which may be
isolated only to our XL-A  or it could be a more wide spread problem that
others have encountered. Consequently,  I would like to know if other
investigators have had a similiar problem and how it was were resolved.
Around March 98 we purchased a 8 cell rotor and the new 4.0 XL-A software.
The latter required new EPROMS. After installation of the software and
EPROMS we had continual intermittent communication errors and the XL-A would
stop scanning. After a long protracted process of changing EPROMS and the
data acquistion board, and then finally a very extended visit by our field
engineer to completely check out the instrument the problem appeared solved
since we were able to run experiments for about 7 months. However, it
reappeared in late November. We were told by our field engineer that Beckman
was aware of communication problems and was rewriting ROM for the XL-A
EPROMS which now required their new version 4.5 software.  New EPROMS and
the 4.5 software were installed. An initially test run of 80 scans with a
water cell looked good but the very next real experiment failed very early
in the run due to a communication error. COM errors are totally
unpredictable, we turn off the XL-A and start a new experimental setup and
it could be fine or fail at any time in the experiment. We have switched
computers and tried version 3.01H XL-A/XL-I software and once again the
pattern of failure is unpredicatable.  The last test suggests that the
problem does not emanate from the computer but is an XL-A problem. Obviously
we need to solve this problem in order to have a truly functional XL-A and
welcome any help we can get towards a resolution. Thanks very much for any
input.

Sincerely,

Jack Lebowitz


Jack Lebowitz
Dept. of Microbiology
520 CHSB
Jack Lebowitz
University of Alabama at Birmingham
Birmingham AL 36294-2041
(205) 934-9475
FAX (205) 975-4621