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Message ID: 593     Entry time: Sun Jun 29 18:58:43 2008
Author: rana 
Type: Summary 
Category: Computers 
Subject: 1e20 is too big for AWG and/or IOVME 
While testing out my matlab/awgstream based McWFS diagnostic script I accidentally put a
huge excitation into
C1:IOO-WFS1_PIT_EXC
. This went to 1e20 and then caused
some SUS to trip and c1susvme2 to go red. I tried booting it via the normal procedures
but it wouldn't come back, even after 2 crate power cycles. I also tried booting AWG
via the vmeBusReset, but that didn't do it. Then I booted c1iovme from the telnet prompt
and then I could restart c1susvme2 successfully.

The reason the excitation was so large is that the following filter command is unstable:
[b,a] = butter(4,[0.02 30]/1024);

The low pass part is OK, but it looks like making such a low frequency digital filter
is not. Que lastima. On the bright side, the code now has some excitation amplitude
checking.
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