编写AD5691 I2C verlog程序

以下是AD5691的I2C Verilog程序示例：

module AD5691_I2C (
  input wire SCLK,
  input wire SDATA,
  input wire SADDR,
  output reg SACK
);

  // I2C slave address
  localparam SLAVE_ADDR = 7'h4C;

  // I2C write bit
  localparam WRITE_BIT = 1'b0;

  // AD5691 command register address
  localparam CMD_REG_ADDR = 4'h0;

  // AD5691 control register address
  localparam CTRL_REG_ADDR = 4'h1;

  // AD5691 power-down register address
  localparam PWRDWN_REG_ADDR = 4'h2;

  reg [7:0] tx_data;
  reg [7:0] rx_data;
  reg [3:0] reg_addr;
  reg        write_mode;

  assign SACK = (SDATA == 1'b0);

  always @(posedge SCLK) begin
    if (SADDR && !write_mode) begin
      // I2C start condition
      tx_data <= {SLAVE_ADDR, WRITE_BIT};
      reg_addr <= CMD_REG_ADDR;
      write_mode <= 1'b1;
    end
    else if (SADDR && write_mode) begin
      // I2C repeated start condition
      tx_data <= {SLAVE_ADDR, WRITE_BIT};
      write_mode <= 1'b1;
    end
    else if (!SADDR && write_mode) begin
      // I2C address and register address sent
      tx_data <= {reg_addr, 8'h00};
      write_mode <= 1'b0;
    end
    else if (!SADDR && !write_mode) begin
      // I2C data sent
      tx_data <= {reg_addr, rx_data};
      write_mode <= 1'b0;
    end
  end

  always @(posedge SCLK) begin
    if (SACK && write_mode) begin
      // I2C address and register address acknowledged
      tx_data <= rx_data;
    end
    else if (SACK && !write_mode) begin
      // I2C data acknowledged
      reg_addr <= reg_addr + 1;
      if (reg_addr == PWRDWN_REG_ADDR) begin
        // Power-down register reached, restart at command register
        reg_addr <= CMD_REG_ADDR;
      end
    end
  end

  assign SDATA = tx_data[7];
  assign rx_data = {SACK, SDATA};

endmodule

这个Verilog程序实现了一个AD5691的I2C从设备。它包括从设备的地址和寄存器地址定义，以及从主设备发送和接收数据的逻辑。在I2C通信期间，程序将在时钟上升沿处理数据和控制信号。完成I2C通信后，程序将从设备返回的数据存储在rx_data寄存器中。您可以根据您的具体需求修改此程序。