Files
UHD-Fairwaves/fpga/sdr_lib/rssi.v
2014-04-07 17:34:55 -07:00

48 lines
1.5 KiB
Verilog

//
// Copyright 2011 Ettus Research LLC
//
// 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 3 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, see <http://www.gnu.org/licenses/>.
//
module rssi (input clock, input reset, input enable,
input [11:0] adc, output [15:0] rssi, output [15:0] over_count);
wire over_hi = (adc == 12'h7FF);
wire over_lo = (adc == 12'h800);
wire over = over_hi | over_lo;
reg [25:0] over_count_int;
always @(posedge clock)
if(reset | ~enable)
over_count_int <= #1 26'd0;
else
over_count_int <= #1 over_count_int + (over ? 26'd65535 : 26'd0) - over_count_int[25:10];
assign over_count = over_count_int[25:10];
wire [11:0] abs_adc = adc[11] ? ~adc : adc;
reg [25:0] rssi_int;
always @(posedge clock)
if(reset | ~enable)
rssi_int <= #1 26'd0;
else
rssi_int <= #1 rssi_int + abs_adc - rssi_int[25:10];
assign rssi = rssi_int[25:10];
endmodule // rssi