pluto_hdl_adi/library/common/ad_datafmt.v

109 lines
3.4 KiB
Verilog

// ***************************************************************************
// ***************************************************************************
// Copyright 2014 - 2017 (c) Analog Devices, Inc. All rights reserved.
//
// In this HDL repository, there are many different and unique modules, consisting
// of various HDL (Verilog or VHDL) components. The individual modules are
// developed independently, and may be accompanied by separate and unique license
// terms.
//
// The user should read each of these license terms, and understand the
// freedoms and responsibilities that he or she has by using this source/core.
//
// This core 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.
//
// Redistribution and use of source or resulting binaries, with or without modification
// of this file, are permitted under one of the following two license terms:
//
// 1. The GNU General Public License version 2 as published by the
// Free Software Foundation, which can be found in the top level directory
// of this repository (LICENSE_GPL2), and also online at:
// <https://www.gnu.org/licenses/old-licenses/gpl-2.0.html>
//
// OR
//
// 2. An ADI specific BSD license, which can be found in the top level directory
// of this repository (LICENSE_ADIBSD), and also on-line at:
// https://github.com/analogdevicesinc/hdl/blob/master/LICENSE_ADIBSD
// This will allow to generate bit files and not release the source code,
// as long as it attaches to an ADI device.
//
// ***************************************************************************
// ***************************************************************************
// data format (offset binary or 2's complement only)
`timescale 1ps/1ps
module ad_datafmt #(
// data bus width
parameter DATA_WIDTH = 16,
parameter BITS_PER_SAMPLE = 16,
parameter DISABLE = 0
) (
// data path
input clk,
input valid,
input [(DATA_WIDTH-1):0] data,
output valid_out,
output [(BITS_PER_SAMPLE-1):0] data_out,
// control signals
input dfmt_enable,
input dfmt_type,
input dfmt_se
);
// internal registers
reg valid_int = 'd0;
reg [(BITS_PER_SAMPLE-1):0] data_int = 'd0;
// internal signals
wire type_s;
wire [(BITS_PER_SAMPLE-1):0] data_out_s;
// data-path disable
generate
if (DISABLE == 1) begin
assign valid_out = valid;
assign data_out = data;
end else begin
assign valid_out = valid_int;
assign data_out = data_int;
end
endgenerate
// if offset-binary convert to 2's complement first
assign type_s = dfmt_enable & dfmt_type;
generate
if (DATA_WIDTH < BITS_PER_SAMPLE) begin
wire signext_s;
wire sign_s;
assign signext_s = dfmt_enable & dfmt_se;
assign sign_s = signext_s & (type_s ^ data[(DATA_WIDTH-1)]);
assign data_out_s[(BITS_PER_SAMPLE-1):DATA_WIDTH] = {((BITS_PER_SAMPLE)-DATA_WIDTH){sign_s}};
end
endgenerate
assign data_out_s[(DATA_WIDTH-1)] = type_s ^ data[(DATA_WIDTH-1)];
assign data_out_s[(DATA_WIDTH-2):0] = data[(DATA_WIDTH-2):0];
always @(posedge clk) begin
valid_int <= valid;
data_int <= data_out_s;
end
endmodule