| `default_nettype none |
| |
| /* |
| Verilog code for playing a RTTL ringtone on a Piezo Speaker |
| |
| Copyright 2022 Milosch Meriac <milosch@meriac.com> |
| Copyright 2022 Jiaxun Yang <jiaxun.yang@flygoat.com> |
| |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions |
| are met: |
| 1. Redistributions of source code must retain the above copyright |
| notice, this list of conditions and the following disclaimer. |
| 2. Redistributions in binary form must reproduce the above copyright |
| notice, this list of conditions and the following disclaimer in the |
| documentation and/or other materials provided with the distribution. |
| 3. Neither the name of the copyright holder nor the names of its |
| contributors may be used to endorse or promote products derived |
| from this software without specific prior written permission. |
| THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| module flygoat_tt02_play_tune #( parameter MAX_COUNT = 100 ) ( |
| input [7:0] io_in, |
| output [7:0] io_out |
| ); |
| |
| wire clk = io_in[0]; |
| wire reset = io_in[1]; |
| wire [1:0] db_sel_in = io_in[3:2]; |
| |
| wire [10:0] db_entry; |
| |
| wire [10:0] flygoat_db_entry; |
| wire [10:0] bh5hso_db_entry; |
| wire [10:0] gm3hso_db_entry; |
| wire [10:0] planetes_db_entry; |
| |
| reg [6:0] note_address; |
| reg [12:0] ticks; |
| reg [6:0] freq, counter; |
| reg [1:0] db_sel_r; |
| reg speaker; |
| |
| reg [3:0] led_out; |
| |
| assign io_out[0] = speaker; |
| assign io_out[1] = ~speaker; |
| assign io_out[5:2] = led_out; |
| assign io_out[7:6] = 2'bzz; |
| |
| always @(posedge clk) begin |
| |
| // if reset, set note_address to 0 |
| if (reset) begin |
| note_address <= 0; |
| ticks <= 0; |
| freq <= 0; |
| counter <= 0; |
| speaker <= 0; |
| db_sel_r <= db_sel_in; |
| end else begin |
| if (!ticks) begin |
| if (note_address<MAX_COUNT) begin |
| note_address <= note_address + 1'b1; |
| end else begin |
| note_address <= 0; |
| end |
| end |
| |
| // tone frequency divider |
| if (counter>0) begin |
| counter <= counter - 1'b1; |
| speaker <= counter >= (freq/2); |
| end else begin |
| counter <= freq; |
| speaker <= 1'b0; |
| end |
| |
| end |
| end |
| |
| always @(negedge clk) begin |
| |
| if (!reset) begin |
| if (ticks>0) begin |
| ticks <= ticks - 1'b1; |
| end else begin |
| // update per-note delay |
| ticks[12:9] <= db_entry[3:0]; |
| ticks[8:0] <= 0; |
| |
| // reset tone generator |
| counter <= db_entry[10:4]; |
| freq <= db_entry[10:4]; |
| end |
| |
| end |
| |
| end |
| |
| // instantiate tune database |
| flygoat_tune_db flygoat_tune_db(.address(note_address), .db_entry(flygoat_db_entry)); |
| gm3hso_tune_db gm3hso_tune_db(.address(note_address), .db_entry(gm3hso_db_entry)); |
| bh5hso_tune_db bh5hso_tune_db(.address(note_address), .db_entry(bh5hso_db_entry)); |
| planetes_tune_db planetes_tune_db(.address(note_address), .db_entry(planetes_db_entry)); |
| |
| genvar i; |
| generate |
| for (i=0; i < 11; i=i+1) begin |
| mux4_cell tune_db_mux ( |
| .a(flygoat_db_entry[i]), |
| .b(gm3hso_db_entry[i]), |
| .c(bh5hso_db_entry[i]), |
| .d(planetes_db_entry[i]), |
| .sel(db_sel_r), |
| .out(db_entry[i]) |
| ); |
| end |
| endgenerate |
| |
| reg [24:0] cnt; |
| always@(posedge clk) begin |
| if(reset) begin |
| cnt <= 25'd0; |
| // 10 khz clk, 1s led peroid |
| end else if(cnt>=(10000-1)) begin |
| cnt <= 25'd0; |
| end else begin |
| cnt <= cnt + 25'd1; |
| end |
| end |
| |
| reg [1:0] led_cnt = 2'd0; |
| always@(posedge clk) begin |
| if(reset) begin |
| led_cnt <= 2'd0; |
| end else if(cnt==(10000-1)) begin |
| if(led_cnt==2'd3) led_cnt <= 2'd0; |
| else led_cnt <= led_cnt + 2'd1; |
| end |
| end |
| |
| always@(*) begin |
| if (reset) begin |
| led_out = 4'b0000; |
| end else begin |
| case(led_cnt) |
| 3'd0: led_out = 4'b1110; |
| 3'd1: led_out = 4'b1101; |
| 3'd2: led_out = 4'b1011; |
| 3'd3: led_out = 4'b0111; |
| default: led_out = 4'b1111; |
| endcase |
| end |
| end |
| |
| endmodule |