基于FPGA设计的不同频率PWM蜂鸣器控制实验Verilog逻辑源码Quartus工程文件+文档说明，用 PWM 控制蜂鸣器，用丌同频率的 pwm 让蜂鸣器发出丌一样的响声，FPGA型号Cyclone4E系列中的EP4CE6F17C8，Quartus版本17.1。
module buzzer_pwm_test(
input clk,
input rst_n,
input key1,
output buzzer
);
parameter IDLE = 0;
parameter BUZZER = 1;
wire button_negedge;
wire pwm_out;
reg[31:0] period;
reg[31:0] duty;
reg[3:0] state;
reg[31:0] timer;
assign buzzer = ~(pwm_out & (state == BUZZER));//buzzer low active
always@(posedge clk or negedge rst_n)
begin
if(rst_n == 1'b0)
begin
period <= 32'd0;
timer <= 32'd0;
duty <= 32'd429496729;
state <= IDLE;
end
else
case(state)
IDLE:
begin
if(button_negedge)
begin
period <= 32'd8590; //The pwm step value
state <= BUZZER;
duty = 32'd12_499_999) //buzzer effictive time 250ms
begin
state <= IDLE;
timer <= 32'd0;
end
else
begin
timer <= timer + 32'd1;
end
end
default:
begin
state <= IDLE;
end
endcase
end
ax_debounce ax_debounce_m0
(
.clk (clk),
.rst (~rst_n),
.button_in (key1),
.button_posedge (),
.button_negedge (button_negedge),
.button_out ()
);
ax_pwm#
(
.N(32)
)
ax_pwm_m0(
.clk (clk),
.rst (~rst_n),
.period (period),
.duty (duty),
.pwm_out (pwm_out)
);
endmodule
2021-04-13 12:02:39
489KB