使用Verilog写一段IIC读写EEPROM的代码
时间: 2023-03-30 17:04:45 浏览: 207
以下是使用 Verilog 写一段 IIC 读写 EEPROM 的代码:
module iic_eeprom(
input clk,
input rst,
input sda,
input scl,
input [7:] addr,
input [7:] data_in,
output reg data_out,
output reg ack
);
reg [7:] addr_reg;
reg [7:] data_reg;
reg [2:] state;
reg [3:] bit_cnt;
reg [7:] shift_reg;
reg [7:] read_data;
parameter IDLE = 3'b000;
parameter START = 3'b001;
parameter WRITE_ADDR = 3'b010;
parameter WRITE_DATA = 3'b011;
parameter READ_ADDR = 3'b100;
parameter READ_DATA = 3'b101;
parameter STOP = 3'b110;
always @(posedge clk) begin
if (rst) begin
state <= IDLE;
bit_cnt <= ;
addr_reg <= ;
data_reg <= ;
shift_reg <= ;
ack <= 1;
end else begin
case (state)
IDLE: begin
if (!sda && scl) begin
state <= START;
bit_cnt <= ;
end
end
START: begin
sda <= ;
if (scl) begin
state <= WRITE_ADDR;
end
end
WRITE_ADDR: begin
if (bit_cnt < 8) begin
sda <= addr_reg[7-bit_cnt];
bit_cnt <= bit_cnt + 1;
end else begin
sda <= 1;
bit_cnt <= ;
state <= WRITE_DATA;
end
end
WRITE_DATA: begin
if (bit_cnt < 8) begin
sda <= data_reg[7-bit_cnt];
bit_cnt <= bit_cnt + 1;
end else begin
sda <= 1;
bit_cnt <= ;
state <= STOP;
end
end
READ_ADDR: begin
if (bit_cnt < 8) begin
sda <= addr_reg[7-bit_cnt];
bit_cnt <= bit_cnt + 1;
end else begin
sda <= 1;
bit_cnt <= ;
state <= START;
end
end
READ_DATA: begin
if (bit_cnt < 8) begin
shift_reg[7-bit_cnt] <= sda;
sda <= ;
bit_cnt <= bit_cnt + 1;
end else begin
sda <= 1;
bit_cnt <= ;
read_data <= shift_reg;
state <= STOP;
end
end
STOP: begin
sda <= ;
if (scl) begin
state <= IDLE;
ack <= 1;
end
end
endcase
end
end
always @(posedge scl) begin
if (!rst) begin
if (state == WRITE_ADDR) begin
addr_reg <= addr;
end else if (state == WRITE_DATA) begin
data_reg <= data_in;
end else if (state == READ_ADDR) begin
addr_reg <= addr;
end else if (state == READ_DATA) begin
shift_reg <= ;
end
end
end
assign data_out = read_data;
endmodule