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author | jcorgan <jcorgan@221aa14e-8319-0410-a670-987f0aec2ac5> | 2008-09-08 01:00:12 +0000 |
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committer | jcorgan <jcorgan@221aa14e-8319-0410-a670-987f0aec2ac5> | 2008-09-08 01:00:12 +0000 |
commit | 61f2f0214c5999ea42a368a4fc99f03d8eb28d1e (patch) | |
tree | e7e24a9adc05ff1422fe3ada9926a51634741b47 /sdr_lib/cic_decim.v | |
download | uhd-61f2f0214c5999ea42a368a4fc99f03d8eb28d1e.tar.gz uhd-61f2f0214c5999ea42a368a4fc99f03d8eb28d1e.tar.bz2 uhd-61f2f0214c5999ea42a368a4fc99f03d8eb28d1e.zip |
Merged r9433:9527 from features/gr-usrp2 into trunk. Adds usrp2 and gr-usrp2 top-level components. Trunk passes distcheck with mb-gcc installed, but currently not without them. The key issue is that when mb-gcc is not installed, the build system skips over the usrp2/firmware directory, and the firmware include files don't get put into the dist tarball. But we can't do the usual DIST_SUBDIRS method as the firmware is a subpackage.
git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@9528 221aa14e-8319-0410-a670-987f0aec2ac5
Diffstat (limited to 'sdr_lib/cic_decim.v')
-rwxr-xr-x | sdr_lib/cic_decim.v | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/sdr_lib/cic_decim.v b/sdr_lib/cic_decim.v new file mode 100755 index 000000000..9a03081b0 --- /dev/null +++ b/sdr_lib/cic_decim.v @@ -0,0 +1,88 @@ +// -*- verilog -*- +// +// USRP - Universal Software Radio Peripheral +// +// Copyright (C) 2003 Matt Ettus +// +// This program is free software; you can redistribute it and/or modify +// it under the terms of the GNU General Public License as published by +// the Free Software Foundation; either version 2 of the License, or +// (at your option) any later version. +// +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License +// along with this program; if not, write to the Free Software +// Foundation, Inc., 51 Franklin Street, Boston, MA 02110-1301 USA +// + + +module cic_decim + #(parameter bw = 16, parameter N = 4, parameter log2_of_max_rate = 7) + (input clock, + input reset, + input enable, + input [7:0] rate, + input strobe_in, + input strobe_out, + input [bw-1:0] signal_in, + output reg [bw-1:0] signal_out); + + localparam maxbitgain = N * log2_of_max_rate; + + wire [bw+maxbitgain-1:0] signal_in_ext; + reg [bw+maxbitgain-1:0] integrator [0:N-1]; + reg [bw+maxbitgain-1:0] differentiator [0:N-1]; + reg [bw+maxbitgain-1:0] pipeline [0:N-1]; + reg [bw+maxbitgain-1:0] sampler; + + integer i; + + sign_extend #(bw,bw+maxbitgain) + ext_input (.in(signal_in),.out(signal_in_ext)); + + always @(posedge clock) + if(reset) + for(i=0;i<N;i=i+1) + integrator[i] <= 0; + else if (enable && strobe_in) + begin + integrator[0] <= integrator[0] + signal_in_ext; + for(i=1;i<N;i=i+1) + integrator[i] <= integrator[i] + integrator[i-1]; + end + + always @(posedge clock) + if(reset) + begin + sampler <= 0; + for(i=0;i<N;i=i+1) + begin + pipeline[i] <= 0; + differentiator[i] <= 0; + end + end + else if (enable && strobe_out) + begin + sampler <= integrator[N-1]; + differentiator[0] <= sampler; + pipeline[0] <= sampler - differentiator[0]; + for(i=1;i<N;i=i+1) + begin + differentiator[i] <= pipeline[i-1]; + pipeline[i] <= pipeline[i-1] - differentiator[i]; + end + end // if (enable && strobe_out) + + wire [bw-1:0] signal_out_unreg; + + cic_dec_shifter #(bw) + cic_dec_shifter(rate,pipeline[N-1],signal_out_unreg); + + always @(posedge clock) + signal_out <= signal_out_unreg; + +endmodule // cic_decim |