Hi all,
I encountered this issue when I first started to play around with the
fft_wideband_real from the CASPER library on Xilinx 14.6
The default bit-width initialization for this block is set at 18_17.
However, when we specify the 'word length' as 14 and 'binary point' as
13, in the mask parameters dialog it returns the following error:
*/The following error occured with the
filename/fft_wideband_real/fft_biplex_real_4x/bi_real_unscr_4x/mirror_spectrum/complex_conj0/imag_negate/neg1
block://
//Illegal parameterization: Binary point//
//Binary point must be less than or equal to number of bits, 14. //
//Binary point is currently set to "17"./**
***
The problem was somewhere between 'fft_wideband_real' and 'imag_negate',
as the error link points. So, I dug down, starting from
'fft_wideband_real_init', until 'bus_negate_init', by following the
functions invoked within each other. I found out that the variable
'bin_pt', that carries the value of the binary point we specified in the
mask parameters, *did not* traverse from 'bi_real_unscr_4x_init' to
'mirror_spectrum_init'. This resulted in 'mirror_spectrum_init'
retaining the default 'bin_pt' value of 17. However, as the 'bit_width'
was correctly transferred as 14, it produced the error above.
I could get the block running by adding the line *'**/bin_pt_in',
num2str(bin_pt), .../* in the 'bi_real_unscr_4x_init' file (anywhere
between lines 495-502), in the current mlib_devel (locally), to pass on
the right value of the user specified 'bin_pt' to the lower layers.
The reason I bring this up is because I noticed that this line is still
missing in the latest mlib_devel at github, which we are soon going to
adapt on Xilinx 14.7, and that might cause the bug to show up again. We
thought it would be a good idea to put this issue out to the CASPER
community to take a look at, and for the users who currently (might)
face a similar error message. If this fix seems reasonable, maybe the
'bi_real_unscr_4x_init' file can be updated on github with the line
*'**/bin_pt_in', num2str(bin_pt), ... /*?
Thanks,
Arindam
