| Rev |
Log message |
Author |
Age |
Path |
| 43 |
Adjusted ignore properties |
dgisselq |
2064d 18h |
/dblclockfft/ |
| 42 |
Switched license info to LGPL from GPL |
dgisselq |
2064d 18h |
/dblclockfft/ |
| 41 |
Updated bench tests for each component |
dgisselq |
2064d 18h |
/dblclockfft/ |
| 40 |
Updated SBY files for formally verifying the FFT |
dgisselq |
2064d 18h |
/dblclockfft/ |
| 39 |
Updated Verilog, added window function demo |
dgisselq |
2064d 18h |
/dblclockfft/ |
| 38 |
Ignores |
dgisselq |
2064d 18h |
/dblclockfft/ |
| 37 |
Software updates |
dgisselq |
2064d 18h |
/dblclockfft/ |
| 36 |
Added several new modes to the FFT
This makes the FFT core generator a generator for a generic
pipelined FFT--whether it be two samples per clock, one
sample per clock, one sample per two clocks, or even one
sample every three clocks.
This version works in simulation, with some formal checks
as well. |
dgisselq |
2323d 23h |
/dblclockfft/ |
| 35 |
TB now handles newer Verilator versions
I also placed verilator -Wall into the verilator Makefile,
turned on the -trace capability (tho nothing uses it), and
placed `default_nettype none into all of the created
Verilog files. |
dgisselq |
2538d 08h |
/dblclockfft/ |
| 34 |
OCTkt #2661: Fixed a problem in longbimpy causing an iverilog error |
dgisselq |
2784d 06h |
/dblclockfft/ |
| 33 |
Updated internal docs, ignore files, no substantial changes. |
dgisselq |
2785d 03h |
/dblclockfft/ |
| 32 |
Fixed the makefile dependency on the static VERILATOR_ROOT. |
dgisselq |
2946d 23h |
/dblclockfft/ |
| 31 |
Thanks to Lesha Birukov, these changes will help to make fftgen.cpp work in a
Microsoft Visual Studio (2012) environment. Further testing is necessary for
proving that it works in (2013+) environments, but I don't have those to test
with. At issue are the functions llround() for rounding a double to a long
long (64-bit integer), mkdir for creating a directory to hold all the Verilog
files in, lstat and S_ISDIR for determining if a directory exists that can be
written to without overwriting a file of the same name, and the access()
macros R_OK, W_OK, X_OK and F_OK--again for determining whether access to a
directory is possible. |
dgisselq |
3210d 09h |
/dblclockfft/ |
| 30 |
Minor documentation edits. |
dgisselq |
3261d 20h |
/dblclockfft/ |
| 29 |
Checking in a lot of changes here. These changes were focused on two
things primarily: 1st the ability to match, in bench testing, the bench
test to the configuration of the generated FFT. For this purpose, the
fftgen program now creates fftsize.h and ifftsize.h header files. These
header files contain the parameters that were used in the creation of the
various verilog files, and therefore the C++ test benches may now be compiled
to match the test files. The 2nd change is the multiply. Based upon a
set of slides from Xilinx, I rebuilt my shiftaddmpy into a longbimpy.
(Think if 'bimpy' as a 'bi', or two-bit, 'mpy', or multiply.) Longbimpy
depends upon bimpy, an optimized 2xN bit multiply--optimized for 6-bit
LUTs with carry chains. Longbimpy simply expands that capability to a
NxN bit multiply. Sadly, the longbimpy approach increased my area on the
chip when it was supposed to be a cheaper multiply, so I may well take it
back out in the future. |
dgisselq |
3418d 06h |
/dblclockfft/ |
| 28 |
This revision represents a lot of work to get the Verilator simulation to now
match the FPGA performance. The big problem turned out to be in the
bit reversal stage, where a '=' was used on a register instead of a '<='.
Neither Verilator nor Vivado complained, but they each treated the result
differently. In addition, a bug was traced to the soft butterfly, butterfly.v,
whereby the delay through the butterfly did not properly change when the
delay through the multiply changed. All of this has been fixed, and now
appears to work and work well in both hardware and simulation. |
dgisselq |
3428d 00h |
/dblclockfft/ |
| 27 |
Minor documentation change. |
dgisselq |
3450d 03h |
/dblclockfft/ |
| 26 |
A lot of updates and upgrades in this release. Specifically, work took place
over the last several days to demonstrate this FFT on an FPGA. It was
demonstrated on the Xilinx Artix-7 found on a Basys-3 development board.
Part of the effort stemmed around making certain that the DSPs were used
optimally, part of it stemmed around making certain that various parts of the
FFT could use block RAM-type memories. The other massive change involved
removing as much unnecessary logic as possible, so that two 16-bit 1k FFTs
could fit onto this part--together with other glue logic. The bottom line,
though, is that it all now works. Specifically, I've tested it successfully
with
fftgen -f <FFTSIZE> -n 16 -m 16 -p 7 -c 1 -x 1
and with FFTSIZEs of 32, 64, 128, 256, 512, and 1024.
Oh, I should mention that there's also an undocumented DEBUG interface to the
part, and I fixed where the Verilog files went when given an argument, so
that they actually went to the directory specified. Minor updates have taken
place to the documentation format, making it match the documentation format
for other opencores projects that I've produced.
On a sadder note, the Verilator simulation fft_tb no longer works. (Yeah, get
that---the FFT implementation works but Verilator does not. Sigh). |
dgisselq |
3450d 06h |
/dblclockfft/ |
| 25 |
The documentation has been changed to bring it closer to the example
specification document. The big change is that the first line, the
headline if you will, of each table has een adjusted to have a gray
background.
The second and bigger change is in the fftgen software itself, or more
specifically to the code that it produces. I had the opportunity to build
the code using Xilinx's ISE and spent some time getting rid of warnings
during the build. As a result, registers that need initial conditions
now have initial conditions. In a similar manner I have trimmed out
registers that were unused. The resulting code continues to pass all
test benches, although I will admit that the automated testing of the
whole fft or ifft via there test benches, fft_tb and ifft_tb, continues
to be a less than automated process than it should be. Therefore, these
test benches always "pass" and only a manual examination of the results
can be used to confirm their success. |
dgisselq |
3500d 07h |
/dblclockfft/ |
| 24 |
Found some bugs in the synchronization code, such that if a reset was
issued residual internal synchronization signals might not get cleared.
These have been fixed.
Other updates have been made to the internal source documentation. |
dgisselq |
3520d 05h |
/dblclockfft/ |
