中断优先级排队电路设计代码

以下是一个简单的中断优先级排队电路的设计代码，其中使用了一个FIFO队列来实现中断请求的排序：

module interrupt_queue(
    input clk,
    input rst,
    input [7:0] interrupt_priority,
    input [7:0] interrupt_request,
    output reg [7:0] interrupt_acknowledge
);

localparam QUEUE_SIZE = 8;
reg [7:0] queue [QUEUE_SIZE-1:0];
reg [2:0] queue_head;
reg [2:0] queue_tail;
reg [7:0] highest_priority;
reg [7:0] highest_priority_index;

always @(posedge clk or posedge rst) begin
    if (rst) begin
        queue_head <= 0;
        queue_tail <= 0;
        highest_priority <= 0;
        highest_priority_index <= 0;
        interrupt_acknowledge <= 0;
    end else begin
        // Update the queue
        if (interrupt_request != 0) begin
            if (queue_tail != queue_head + QUEUE_SIZE - 1) begin
                queue[queue_tail] <= interrupt_priority;
                queue_tail <= queue_tail + 1;
            end
        end
        if (queue_head != queue_tail) begin
            highest_priority <= queue[queue_head];
            highest_priority_index <= queue_head;
            queue_head <= queue_head + 1;
        end else begin
            highest_priority <= 0;
            highest_priority_index <= 0;
        end

        // Generate the interrupt acknowledge signal
        if (interrupt_request != 0 && interrupt_priority == highest_priority) begin
            interrupt_acknowledge <= 1;
        end else begin
            interrupt_acknowledge <= 0;
        end
    end
end

endmodule

在这个Verilog代码中，我们使用了一个大小为8的FIFO队列来存储中断请求的优先级码。当一个中断请求到来时，它的优先级码会被存储在队列的末尾；当CPU准备响应中断时，队列中的第一个元素（即优先级最高的中断请求）会被弹出，并且相应的中断服务程序会被调用。如果队列为空，则中断响应逻辑会被禁用。