根据FPGA实验板cyclone5功能,设计四个数码管显示的数字时钟; 要求:数字时钟能够准确计时并显示; 开机显示00; 具备控制功能按键有3个:清零、暂停、计时开始。 用Verilog编写代码
时间: 2023-11-22 09:53:21 浏览: 41
以下是一个可能的Verilog代码实现:
```verilog
module digital_clock(
input clk,
input reset,
input clear,
input pause,
input start,
output [3:0] seg_out,
output [3:0] dig_sel
);
reg [23:0] count;
reg [1:0] sec;
reg [1:0] min;
reg [1:0] hour;
reg [3:0] seg;
reg [1:0] dig;
parameter [3:0] digit[10] = {4'b0011111, 4'b0000110, 4'b0101101, 4'b0100111,
4'b0110010, 4'b0110111, 4'b0111111, 4'b0000011,
4'b0111111, 4'b0110111};
always @(posedge clk or posedge reset) begin
if (reset) begin
count <= 0;
sec <= 0;
min <= 0;
hour <= 0;
seg <= digit[0];
dig <= 2'b00;
end else if (pause) begin
// do nothing, keep the current values
end else if (start) begin
count <= count + 1;
if (count == 24000000) begin // 1 second has passed
count <= 0;
sec <= sec + 1;
if (sec == 10) begin
sec <= 0;
min <= min + 1;
if (min == 10) begin
min <= 0;
hour <= hour + 1;
if (hour == 10) begin
hour <= 0;
end
end
end
end
// update the seg and dig values based on the current time
case (dig)
2'b00: seg <= digit[hour];
2'b01: seg <= digit[min];
2'b10: seg <= digit[sec];
2'b11: seg <= 4'b0000000; // no display
endcase
end else if (clear) begin
sec <= 0;
min <= 0;
hour <= 0;
seg <= digit[0];
dig <= 2'b00;
end
end
// multiplex the seg outputs to the four displays
always @(posedge clk) begin
case (dig)
2'b00: dig_sel <= 4'b1110;
2'b01: dig_sel <= 4'b1101;
2'b10: dig_sel <= 4'b1011;
2'b11: dig_sel <= 4'b0111;
endcase
seg_out <= seg;
dig <= dig + 1;
if (dig == 2'b11) begin
dig <= 2'b00;
end
end
endmodule
```
该模块使用一个24位的计数器来计算每秒的时间,并且使用一个状态机实现了对时钟的暂停、开始、清零功能。在每个时钟边沿时,数字时钟的值被更新,并将四个数码管的输出转换为七段码。在每个时钟周期内,将四个数码管按顺序选择并输出其相应的七段码。