用verilog写一个ahb转apb的桥

好的，这是一个比较复杂的设计，需要涉及到AHB和APB总线的协议，以及信号的转换和数据的传输。以下是一个简单的verilog代码示例，仅供参考：

module AHB_to_APB (
    input         HCLK,
    input         HRESETn,
    input  [31:0] HADDR,
    input  [1:0]  HSIZE,
    input         HBURST,
    input         HPROT,
    input  [31:0] HWDATA,
    output        HREADY,
    output        HRESP,
    output        PCLK,
    output        PRESETn,
    output [31:0] PADDR,
    output [1:0]  PSEL,
    output        PENABLE,
    output        PWRITE,
    output [31:0] PWDATA,
    input  [31:0] PRDATA
);

// AHB to APB bridge logic
reg [31:0] reg_addr;
reg [31:0] reg_data;
reg        reg_wr;
reg        reg_rd;
reg        pclk_div;
reg        pwrite;
reg        pready;

// AHB to APB signal conversion
assign PSEL    = reg_addr[11:10];
assign PADDR   = reg_addr[9:2];
assign PWRITE  = reg_wr;
assign PWDATA  = reg_data;
assign PCLK    = HCLK;
assign PRESETn = HRESETn;

// APB to AHB signal conversion
assign HREADY = pready;
assign HRESP  = 'b00;

// APB clock divider
always @(posedge HCLK) begin
    if (pclk_div == 0) begin
        PENABLE <= 1;
        pclk_div <= 1;
    end else if (pclk_div == 1) begin
        PENABLE <= 0;
        pclk_div <= 0;
    end
end

// APB read/write logic
always @(posedge PCLK) begin
    if (PENABLE) begin
        reg_rd   <= ~PWRITE;
        reg_wr   <= PWRITE;
        reg_addr <= PADDR;
        reg_data <= PWDATA;
        pready   <= 1;
    end else begin
        pready <= 0;
    end
end

// AHB read/write logic
always @(posedge HCLK) begin
    if (HRESETn == 0) begin
        reg_rd   <= 0;
        reg_wr   <= 0;
        reg_addr <= 0;
        reg_data <= 0;
        pready   <= 0;
    end else if (HBURST == 0 && HSIZE == 2'b10 && HREADY) begin
        reg_rd   <= 1;
        reg_wr   <= 0;
        reg_addr <= HADDR;
        pready   <= 0;
    end else if (HBURST == 0 && HSIZE == 2'b10 && reg_rd && HREADY) begin
        reg_rd   <= 0;
        reg_wr   <= 0;
        reg_addr <= 0;
        pready   <= 1;
        PRDATA   <= reg_data;
    end else if (HBURST == 0 && HSIZE == 2'b10 && reg_wr && HREADY) begin
        reg_rd   <= 0;
        reg_wr   <= 0;
        reg_addr <= 0;
        pready   <= 1;
    end else if (HBURST == 0 && HSIZE == 2'b00 && HREADY) begin
        reg_rd   <= 1;
        reg_wr   <= 0;
        reg_addr <= HADDR;
        pready   <= 0;
    end else if (HBURST == 0 && HSIZE == 2'b00 && reg_rd && HREADY) begin
        reg_rd   <= 0;
        reg_wr   <= 0;
        reg_addr <= 0;
        pready   <= 1;
        PRDATA   <= reg_data;
    end else if (HBURST == 0 && HSIZE == 2'b00 && reg_wr && HREADY) begin
        reg_rd   <= 0;
        reg_wr   <= 0;
        reg_addr <= 0;
        pready   <= 1;
    end else if (HBURST == 1 && HSIZE == 2'b10 && HREADY) begin
        reg_rd   <= 1;
        reg_wr   <= 0;
        reg_addr <= HADDR;
        pready   <= 0;
    end else if (HBURST == 1 && HSIZE == 2'b10 && reg_rd && HREADY) begin
        reg_rd   <= 1;
        reg_wr   <= 0;
        reg_addr <= reg_addr + 4;
        PRDATA   <= reg_data;
    end else if (HBURST == 1 && HSIZE == 2'b10 && reg_wr && HREADY) begin
        reg_rd   <= 0;
        reg_wr   <= 1;
        reg_addr <= reg_addr + 4;
    end else if (HBURST == 1 && HSIZE == 2'b00 && HREADY) begin
        reg_rd   <= 1;
        reg_wr   <= 0;
        reg_addr <= HADDR;
        pready   <= 0;
    end else if (HBURST == 1 && HSIZE == 2'b00 && reg_rd && HREADY) begin
        reg_rd   <= 1;
        reg_wr   <= 0;
        reg_addr <= reg_addr + 4;
        PRDATA   <= reg_data;
    end else if (HBURST == 1 && HSIZE == 2'b00 && reg_wr && HREADY) begin
        reg_rd   <= 0;
        reg_wr   <= 1;
        reg_addr <= reg_addr + 4;
    end
end

endmodule

该代码使用了一个简单的状态机来实现AHB到APB的转换，同时需要注意时序问题和信号的正确对应。此代码仅供参考，实际使用中需要根据具体需求进行修改和优化。