I would conjecture that reinstalling ISE will not solve your problem,
since nothing in the ISE directories is normally changed anyways (unless
you hacked something?) I have also personally experienced issues
involving upper-case characters in either my model-name or block names
(I think it was model name).
I would suggest getting in touch with Jonathon Kocz (CC'ed), who has
experience with this issue. I believe he resolved it by black-boxing
the FFT.
Cheers!
https://casper.berkeley.edu/wiki/images/a/a4/Black_box_memo.pdf
--Ryan Monroe
On 11/11/2015 10:43 AM, Michael D'Cruze wrote:
Hi Dan,
I have read about such problems. I’m using Red Hat version 6.7. We
were originally using Debian but switched exclusively because it was,
at the time, the only linux O/S that Xilinx would support.
Reinstalling the O/S isn’t really an option, but trashing and
reinstalling ISE might be…. This hasn’t worked for Andrew Martens et
al., however.
BW
Michael
*From:*[email protected] [mailto:[email protected]] *On
Behalf Of *Dan Werthimer
*Sent:* 11 November 2015 18:38
*To:* Michael D'Cruze
*Cc:* Jack Hickish; [email protected]
*Subject:* Re: [casper] FFT woes
hi michael,
what operating system are you using?
we have seen problems where the FFT works in simulation,
and doesn't produce correct results on the FPGA when we were compiling
using a non-xilinx supported
operating system.
the problem occurred only for large FFT's - i think 8K or larger.
best wishes,
dan
On Wed, Nov 11, 2015 at 7:34 AM, Michael D'Cruze
<[email protected]
<mailto:[email protected]>> wrote:
Hi Jack
Sorry it’s taken me so long to come back (I’m going to write back to
everyone shortly). I’ve been chasing a few hunches I’ve had which
might have exonerated the FFT, but to no avail. Indeed the FFT does
simulate OK, but in the majority of cases in hardware every other
channel is a zero. I say in the majority of cases, because in one or
two cases the design works correctly. I have not been able to find a
reason for this yet.
BW
Michael
*From:*Jack Hickish [mailto:[email protected]
<mailto:[email protected]>]
*Sent:* 03 November 2015 01:01
*To:* Michael D'Cruze
*Cc:* [email protected] <mailto:[email protected]>
*Subject:* Re: [casper] FFT woes
Hi Michael,
Just so everyone is on the same page -- does your issue only show up
in hardware like Andrew/Jonathon's - i.e., in simulation the FFT works ok?
Jack
On 3 November 2015 at 00:57, Michael D'Cruze
<[email protected]
<mailto:[email protected]>> wrote:
Dear all,
Following on from the email thread from Jonathan Kocz and Andrew
Martens about odd FFT outputs….
I’ve been experiencing similar inexplicable problems for a while now.
Every other channel in my output is invariably a zero. I’ve tried
everything I can think of, including solutions along the lines of
those observed to work by Jonathan and Andrew (black-boxing, changing
mask parameters etc.), in addition to wiping clean my libraries and
re-syncing with casper-astro-soak-test. I’ve even re-drawn the entire
model from scratch. The results are always the same. Below is a link
to an example output.
https://dl.dropboxusercontent.com/u/38103354/32k_test_image.png
Hopefully it’s clear from a_0 (note that a_0 is zoomed in, a_1 is not)
that every other channel outputs zero, and the interleaved a_0 and a_1
spectra (to form the full 32k channel spectrum) are interleaving
correctly to produce pairs of zeroes. I’ve been trying various things
for quite a while now, without success and would appreciate some
suggestions…!
Thanks
Michael
