pluto_hdl_adi/library/axi_mc_speed/delay_30_degrees.v

194 lines
5.8 KiB
Verilog

// ***************************************************************************
// ***************************************************************************
// Copyright 2014 - 2017 (c) Analog Devices, Inc. All rights reserved.
//
// Each core or library found in this collection may have its own licensing terms.
// The user should keep this in in mind while exploring these cores.
//
// Redistribution and use in source and binary forms,
// with or without modification of this file, are permitted under the terms of either
// (at the option of the user):
//
// 1. The GNU General Public License version 2 as published by the
// Free Software Foundation, which can be found in the top level directory, or at:
// https://www.gnu.org/licenses/old-licenses/gpl-2.0.en.html
//
// OR
//
// 2. An ADI specific BSD license as noted in the top level directory, or on-line at:
// https://github.com/analogdevicesinc/hdl/blob/dev/LICENSE
//
// ***************************************************************************
// ***************************************************************************
`timescale 1ns / 1ps
module delay_30_degrees
//----------- Paramters Declarations -------------------------------------------
//----------- Ports Declarations -----------------------------------------------
(
input clk_i,
input rst_i,
input [31:0] offset_i, // offset register
input [2:0] position_i, // input position
output reg [2:0] position_o // delayed with 30 degrees position
);
//------------------------------------------------------------------------------
//----------- Local Parameters -------------------------------------------------
//------------------------------------------------------------------------------
localparam MAX_SPEED_COUNT = 32'h1000000;
//State machine
localparam RESET = 6'b000001;
localparam INIT = 6'b000010;
localparam CHANGE_POSITION = 6'b000100;
localparam DELAY_30_DEGREES = 6'b001000;
localparam APPLY_CHANGE = 6'b010000;
localparam IDLE = 6'b100000;
//------------------------------------------------------------------------------
//----------- Registers Declarations -------------------------------------------
//------------------------------------------------------------------------------
reg [5:0] state = RESET; // current state
reg [5:0] next_state = RESET; // next state
reg [2:0] position_old = 3'h0; // saves the latest position
reg [31:0] speed_count = 32'h0; // counts the current speed of rotation
reg [31:0] speed_divider = 32'h0; // divides the speed of rotation by 2, correspoding to 30 degrees
reg [31:0] delay_count = 32'h0; // Applied the delay to the input signal
//------------------------------------------------------------------------------
//----------- Assign/Always Blocks ---------------------------------------------
//------------------------------------------------------------------------------
// State transitions
always @*
begin
next_state = state;
case (state)
RESET:
begin
next_state = INIT;
end
INIT:
begin
if (position_i != position_old)
begin
next_state = CHANGE_POSITION;
end
end
CHANGE_POSITION:
begin
next_state = DELAY_30_DEGREES;
end
DELAY_30_DEGREES:
begin
if( delay_count > speed_divider)
begin
next_state = APPLY_CHANGE;
end
end
APPLY_CHANGE:
begin
next_state = IDLE;
end
IDLE:
begin
if (position_i != position_old)
begin
next_state = CHANGE_POSITION;
end
end
default:
begin
next_state = RESET;
end
endcase
end
always @(posedge clk_i)
begin
case(state)
RESET:
begin
speed_count <= 0;
speed_divider <= 0;
position_o <= 3'b1;
end
INIT:
begin
if (speed_count < MAX_SPEED_COUNT)
begin
speed_count <= speed_count + 1;
end
end
CHANGE_POSITION:
begin
speed_divider <= speed_count >> 1 ;
speed_count <= 0;
delay_count <= 0;
end
DELAY_30_DEGREES:
begin
if (speed_count < MAX_SPEED_COUNT)
begin
speed_count <= speed_count + 1;
end
delay_count <= delay_count + 1;
end
APPLY_CHANGE:
begin
if (position_i == 3'b101)
begin
position_o <= 100;
end
if (position_i == 3'b100)
begin
position_o <= 110;
end
if (position_i == 3'b110)
begin
position_o <= 010;
end
if (position_i == 3'b010)
begin
position_o <= 011;
end
if (position_i == 3'b011)
begin
position_o <= 001;
end
if (position_i == 3'b001)
begin
position_o <= 101;
end
position_old <= position_i;
if (speed_count < MAX_SPEED_COUNT)
begin
speed_count <= speed_count + 1;
end
end
IDLE:
begin
if (speed_count < MAX_SPEED_COUNT)
begin
speed_count <= speed_count + 1;
end
end
endcase
end
always @ (posedge clk_i)
begin
if(rst_i == 1'b1)
begin
state <= RESET;
end
else
begin
state <= next_state;
end
end
endmodule