EEPROM的操作---SPI接口和I2C接口

 

参考:http://blog.csdn.net/yuanlulu/article/details/6163106

 ROM最初不能编程,出厂什么内容就永远什么内容,不灵活。后来出现了PROM,可以自己写入一次,要是写错了,只能换一片,自认倒霉。人类文明不断进步,终于出现了可多次擦除写入的EPROM,每次擦除要把芯片拿到紫外线上照一下,想一下你往单片机上下了一个程序之后发现有个地方需要加一句话,为此你要把单片机放紫外灯下照半小时,然后才能再下一次,这么折腾一天也改不了几次。历史的车轮不断前进,伟大的EEPROM出现了,拯救了一大批程序员,终于可以随意的修改rom中的内容了

  EEPROM的全称是“电可擦除可编程只读存储器”,即Electrically Erasable Programmable Read-Only Memory。是相对于紫外擦除的rom来讲的。但是今天已经存在多种EEPROM的变种,变成了一类存储器的统称.这种rom的特点是可以随机访问和修改任何一个字节,可以往每个bit中写入0或者1。这是最传统的一种EEPROM,掉电后数据不丢失,可以保存100年,可以擦写100w次。具有较高的可靠性,但是电路复杂/成本也高。因此目前的EEPROM都是几十千字节到几百千字节的,绝少有超过512K的。

  EEPROM的接口分为两种:SPI和I2C。

      SPI接口为四线,型号如AT25XXX。 

    

 

      I2C接口为2线,型号如24CL02/04/XX.

        

    这两种EEPROM的操作主要按SPI 和I2C的协议操作就可以了,不过也有一些需要注意的地方。在这里记录下来,不涉及细节的处理。

      对于SPI接口的EEPROM:

    1、在写数据的时候需要先写WR_EN的命令,然后在按SPI写写操作。读的时候不需要先写WR_EN.

                 

    2、WR_EN 和WR_DATA 的操作之间要隔一段时间,如10us,不能写完WR_EN就写WR_DATA,否则数据将不能被写入。

         3、WR_DATA操作送入EEPROM之后,要等待一段时间,等EEPROM将数据写入内部,时间长短可以参考datasheet中的一个参数 write_cycle。

       

    4、RD_DATA操作到下一次的WR_EN/WR_DATA命令之间也要间隔一段时间,如400us.

    5、SPI协议的最后一个SPI_CLK也要保证完整,有低有高,不能只有一半,如将SPI_CLK拉高之后不拉低就将SPI_CS信号拉低。

      

     example: verilog 

    EEPROM--SPI interface     

  
module EE_WR(
//------------outputs-----------
output   EE_SI, 
output   EE_CSb,
output   EE_SCK, 
input    EE_SO,
//------------inputs------------
input clk,//50MHZ
input rst
)/*synthesis noprune*/;

 parameter  cmd_wr_en =8'h06         /* synthesis keep */;
 parameter  cmd_wr_sr =16'h0180      /* synthesis keep */; //16'h018C all block are protected
 parameter  cmd_rd_sr =8'h05         /* synthesis keep */;
 parameter  cmd_wr_op =536'h020000_63555560595857565554535251504948474645444342414039383736353433323130292827262524232221201918171615141312111009080706050403020100  /* synthesis keep */;
 //parameter  cmd_wr_op =32'h020000_f5 /* synthesis keep */;
 parameter  cmd_rd_op =24'h030000    /* synthesis keep */;
    
 parameter  tck_delay = 4'd6;
 parameter  num_data_bit = 12'd512;

 parameter  IDLE = 5'd0;
 parameter  WR_EN_1 = 5'd1;
 parameter  WR_EN_2 = 5'd2;
 parameter  WR_EN_3 = 5'd3;
 parameter  WR_EN_4 = 5'd4;
 parameter  WR_EN_5 = 5'd5;

 parameter  WR_SR_1 = 5'd6;
 parameter  WR_SR_2 = 5'd7;
 parameter  WR_SR_3 = 5'd8;
 parameter  WR_SR_4 = 5'd9;
 parameter  WR_SR_5 = 5'd10; 
 
 parameter  RD_SR_1 = 5'd11;
 parameter  RD_SR_2 = 5'd12;
 parameter  RD_SR_3 = 5'd13;
 parameter  RD_SR_4 = 5'd14;
 parameter  RD_SR_5 = 5'd15;
 parameter  RD_SR_6 = 5'd16;
 parameter  RD_SR_7 = 5'd17; 
 
 parameter  WR_DATA_1 = 5'd18;
 parameter  WR_DATA_2 = 5'd19;
 parameter  WR_DATA_3 = 5'd20;
 parameter  WR_DATA_4 = 5'd21;
 parameter  WR_DATA_5 = 5'd22; 
 
 parameter  RD_DATA_1 = 5'd23;
 parameter  RD_DATA_2 = 5'd24;
 parameter  RD_DATA_3 = 5'd25;
 parameter  RD_DATA_4 = 5'd26;
 parameter  RD_DATA_5 = 5'd27;
 parameter  RD_DATA_6 = 5'd28;
 parameter  RD_DATA_7 = 5'd29; 
 
 
 
reg   [31:0]   cnt;

always @(posedge clk or negedge rst ) 
 begin
  if(rst == 0 )  cnt <= 0;
  else if(cnt == 32'd500_000_000)   cnt <= 32'd500_000_000;  
  else cnt <= cnt + 1;
 end
 
 wire    wr_en /* synthesis keep */;
 wire    wr_op /* synthesis keep */;
 wire    rd_op /* synthesis keep */;
 wire    rd_sr /* synthesis keep */;
 wire    wr_sr /* synthesis keep */; 

  assign  wr_en = (cnt == 32'd000_000_500);  
  assign  rd_sr = (cnt == 32'd000_000_000); 
  assign  wr_sr = (cnt == 32'd000_000_000); 
  assign  wr_op = (cnt == 32'd000_001_000); 
  assign  rd_op = (cnt == 32'd001_000_000);
  
 
 reg   [4:0]   state;
 reg   [3:0]   delay;
 reg   [11:0]  num;
 reg   [7:0]   data_sr;
 reg   [7:0]   data_rd;
 
 reg      spi_clk;
 reg      spi_cs;
 reg      spi_si;  
 
 always @(posedge clk or negedge rst ) 
 begin
  if(rst == 0 )  begin
    spi_clk <= 0;
     spi_cs <= 1;
     spi_si <= 0;
     delay <= 0;
     num <= 0;
     state <= IDLE;
    data_sr    <= 0; 
     data_rd<= 0;
    end
 else begin
   case(state) 
     IDLE : begin
         spi_clk <= 0;
         spi_cs <= 1;
         spi_si <= 0;
         delay <= 0;
         num <= 0;
         data_sr    <= 0; 
         data_rd <= 0;
         
       if(wr_en)  state <= WR_EN_1; 
//        else if(wr_sr) state <= WR_SR_1; 
//         else if(rd_sr) state <= RD_SR_1; 
         else if(wr_op) state <= WR_DATA_1; 
         else if(rd_op) state <= RD_DATA_1 ;       
        else  state <= state;
     end
//-------------wr_en-------------    
   WR_EN_1: begin    //拉低CS
        spi_clk <= 0;
         spi_cs <= 0;
         num <= 7;
        if(delay == tck_delay)  begin state <= state + 1;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1; end
     end      
    WR_EN_2: begin   //sck 下降沿
        spi_clk <= 0;
         spi_si <= cmd_wr_en[num];
         if(delay == tck_delay)  begin  state <= state + 1;  delay <= 0; end             
        else  begin  state <= state;  delay <= delay + 1;   end
     end   
      
      
    WR_EN_3: begin   //sck 上升沿
        spi_clk <= 1;
         spi_si <= spi_si;
        if(delay == tck_delay) begin
            if(num == 0) begin state <= state + 1; delay <= 0;  end
           else begin state <= WR_EN_2; delay <= 0;  num <= num - 1; end    
         end
        else  begin  state <= state;  delay <= delay + 1;  end
     end 
  
   WR_EN_4: begin   //SCK 下降沿延时一个
        spi_clk <= 0;
         spi_si <= spi_si;
         if(delay == tck_delay)  begin state <= state + 1;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1;   end
     end    
   WR_EN_5: begin   //CS 拉高
        spi_cs <= 1;
        spi_clk<= 0;
         spi_si <= 0;
         if(delay == tck_delay)  begin state <= IDLE;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1;   end
     end   
    
 //-------------wr_sr-------------
  WR_SR_1: begin    //拉低CS
        spi_clk <= 0;
         spi_cs <= 0;
         num <= 15;
         spi_si <= 0;
        if(delay == tck_delay)  begin state <= state + 1;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1;  end
     end
  WR_SR_2: begin   //sck 下降沿
        spi_clk <= 0;         
         spi_si <= cmd_wr_sr[num];
         if(delay == tck_delay)  begin state <= state + 1; delay <= 0; end    
        else  begin  state <= state;  delay <= delay + 1;   end
     end             
  WR_SR_3: begin   //sck 上升沿
        spi_clk <= 1;
         spi_si <= spi_si;
        if(delay == tck_delay)  begin 
            if(num == 0) begin  state <= state + 1;  delay <= 0;   end
             else  begin  state <= WR_SR_2;  delay <= 0; num <= num -1;  end
          end
        else  begin  state <= state;  delay <= delay + 1;  end
     end 
  WR_SR_4: begin   //SCK 下降沿延时一个
        spi_clk <= 0;
         spi_si <= spi_si;
         if(delay == tck_delay)  begin state <= state + 1;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1;   end
     end    
  WR_SR_5: begin   //CS 拉高
        spi_cs <= 1;
        spi_clk<= 0;
         spi_si <= 0;
         if(delay == tck_delay)  begin state <= IDLE;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1;   end
     end     
 
 //-----rd_sr-----------
   RD_SR_1: begin    //拉低CS
        spi_clk <= 0;
         spi_cs <= 0;
         num <= 7;
         data_sr    <= 0; 
         spi_si <= 0;
        if(delay == tck_delay)  begin state <= state + 1;  delay <= 0;  end
        else  begin  state <= state;  delay <=delay + 1;  end
     end
    RD_SR_2: begin     //sck 下降沿
        spi_clk <= 0;
         spi_si <= cmd_rd_sr[num];
         if(delay == tck_delay)  begin state <= state + 1;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1;   end
     end 
   RD_SR_3: begin   //sck 上升沿
        spi_clk <= 1;
         spi_si <= spi_si;
        if(delay == tck_delay)  begin 
            if(num == 0) begin state <= state + 1;  delay <= 0; num <= 7;  end
           else  begin state <= RD_SR_2;  delay <= 0; num <= num - 1;  end
          end         
        else  begin  state <= state;  delay <= delay + 1;  end
     end     
    RD_SR_4: begin    //read SCK 下降沿
        spi_clk <= 0;
         spi_si <= 0;          
         data_sr <= data_sr;
         if(delay == tck_delay)  begin state <= state + 1;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1;   end
     end 
    RD_SR_5: begin    //READ sck 上升沿
        spi_clk <= 1;
         data_sr[num]    <= EE_SO;
        if(delay == tck_delay)  begin 
            if(num == 0) begin state <= state + 1;  delay <= 0;  end
           else  begin state <= RD_SR_4;  delay <= 0; num <= num - 1;  end
          end         
        else  begin  state <= state;  delay <= delay + 1;  end
     end     
   RD_SR_6: begin  //SCK 下降沿延时一个
       spi_clk <= 0;
         data_sr <= data_sr;
         if(delay == tck_delay)  begin state <= state + 1;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1;   end
     end     
     RD_SR_7: begin  //CS拉高  
         spi_cs <= 1;
         spi_clk<= 0;
          spi_si <= 0;
          if(delay == tck_delay)  begin state <= IDLE;  delay <= 0;  end
         else  begin  state <= state;  delay <= delay + 1;   end
      end     

  //---------------------wr_data------------------
   WR_DATA_1: begin    //拉低CS
        spi_clk <= 0;
         spi_cs <= 0;
        spi_si <= 0;
         num <= num_data_bit + 23;
        if(delay == tck_delay)  begin state <= state + 1;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1;  end
     end
    WR_DATA_2: begin  //SCK下降沿
        spi_clk <= 0;
         spi_si <= cmd_wr_op[num];
         if(delay == tck_delay)  begin  state <= state + 1;  delay <= 0;   end
        else  begin  state <= state;  delay <= delay + 1;   end
     end 
        
   WR_DATA_3: begin //SCK 上升沿    
        spi_clk <= 1;
         spi_si <= spi_si;
        if(delay == tck_delay)  begin 
           if(num == 0)   begin   state <= state + 1; delay <= 0;  end
           else  begin state <= WR_DATA_2;  delay <= 0;  num <= num - 1; end
            end
        else  begin  state <= state;  delay <= delay + 1;   end
     end 
    WR_DATA_4: begin  //SCK延时下降沿
        spi_clk <= 0;
         spi_si <=  0;
         if(delay == tck_delay)  begin  state <= state + 1;  delay <= 0;   end
        else  begin  state <= state;  delay <= delay + 1;   end
     end  
    WR_DATA_5:  begin  //CS拉高  
         spi_cs <= 1;
         spi_clk<= 0;
          spi_si <= 0;
          if(delay == tck_delay)  begin state <= IDLE;  delay <= 0;  end
         else  begin  state <= state;  delay <= delay + 1;   end
      end 
        
  //---------------------rd_data-------------------
  RD_DATA_1: begin    //拉低CS
        spi_clk <= 0;
         spi_cs <= 0;
        spi_si <= 0;
         num <= 23;
        if(delay == tck_delay)  begin state <= state + 1;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1;  end
     end
    RD_DATA_2: begin  //SCK下降沿
        spi_clk <= 0;
         spi_si <= cmd_rd_op[num];
         if(delay == tck_delay)  begin  state <= state + 1;  delay <= 0;   end
        else  begin  state <= state;  delay <= delay + 1;   end
     end          
   RD_DATA_3: begin //SCK 上升沿    
        spi_clk <= 1;
         spi_si <= spi_si;
        if(delay == tck_delay)  begin 
           if(num == 0)   begin   state <= state + 1; delay <= 0;   num <= num_data_bit - 1; end
           else  begin state <= RD_DATA_2;  delay <= 0;  num <= num - 1; end
            end
        else  begin  state <= state;  delay <= delay + 1;   end
     end 
    RD_DATA_4: begin    //read SCK 下降沿
        spi_clk <= 0;
         spi_si <= 0;         
         data_rd <= data_rd;
         if(delay == tck_delay)  begin state <= state + 1;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1;   end
     end 
    RD_DATA_5: begin    //READ sck 上升沿
        spi_clk <= 1;
         data_rd[num]    <= EE_SO;
        if(delay == tck_delay)  begin 
            if(num == 0) begin state <= state + 1;  delay <= 0;  end
           else  begin state <= RD_DATA_4;  delay <= 0; num <= num - 1;  end
          end         
        else  begin  state <= state;  delay <= delay + 1;  end
     end     
   RD_DATA_6: begin  //SCK 下降沿延时一个
       spi_clk <= 0;
         data_rd <= data_rd;
         if(delay == tck_delay)  begin state <= state + 1;  delay <= 0;  end
        else  begin  state <= state;  delay <= delay + 1;   end
     end     
    RD_DATA_7 :begin  //CS拉高  
         spi_cs <= 1;
         spi_clk<= 0;
          spi_si <= 0;
          if(delay == tck_delay)  begin state <= IDLE;  delay <= 0;  end
         else  begin  state <= state;  delay <= delay + 1;   end
      end        
   default : state <= 0;
  endcase
 end
end 


 assign  EE_CSb = spi_cs;
 assign  EE_SCK = spi_clk;
 assign  EE_SI  = spi_si;
 
endmodule 
View Code

   tb: 

  
 `timescale 1 ps/1 ps
  
  module EE_WR_tb ;
   
    wire   EE_SI; 
    wire   EE_CSb;
    wire   EE_SCK; 
    reg    EE_SO;

//------------inputs------------
   reg      clk;//50MHZ
   reg      rst;
  
   
   EE_WR u0_EE_WR(
//------------outputs-----------
    .EE_SI(EE_SI), 
    .EE_CSb(EE_CSb),
    .EE_SCK(EE_SCK), 
    .EE_SO(EE_SO),
    
//------------inputs------------
   .clk(clk),//50MHZ
   .rst(rst)
 )/*synthesis noprune*/;


  parameter T = 20000;
  
  always #(T/2)  clk = ~clk;
  
  initial 
    begin
       clk = 0;
        rst =0;
        
        
        #(300*T)  $stop;
        
        #(200*T)  rst =1; 
        
   end
    
 endmodule 
    
View Code

 对于I2C的接口:

    1、读写之间按I2C的协议进行就可以。

    2、在读取数据时候,master在接收完8bit数据之后,需要给从机发一个ACK(输出一个SDA =0)。注意读取的时候ACK是由Master发出的,在写数据的时候ACK是由slaver发出的。

   可以参考:http://blog.csdn.net/lingfeng5/article/details/73361833

   3、写数据同样也有一定的write_cycle. 参考datasheet.

     

  example: verilog

  View Code
  
// `define SIM   //if run modelsim, enable 
 
 module  eeprom_data(
    input            clk,
    input            rst_n,
    
    output                     wr_en,
    output    reg [7:0]   wr_addr,
    output    reg [7:0]   wr_data,
    output    reg           wr_flag,
    
    output                     rd_en,
    output    reg [7:0]    rd_addr,
    input          [7:0]    rd_data,
    output    reg           rd_flag,
    
   input                rd_wrdata_en,    //only one clk cycle high time
    input          wr_rddata_en
    
 
 );
     
    reg  [7:0]  wr_cnt;
    reg  [7:0]  rd_cnt;
 
  
    reg   [31:0]    cnt;
    
    reg    [5:0]        rd_wrdata_en_flag;
  always @(posedge clk or negedge rst_n)
    begin 
         if(rst_n == 0) rd_wrdata_en_flag <= 6'd0;
         else rd_wrdata_en_flag <= {rd_wrdata_en_flag[5:0],rd_wrdata_en};            
    end
            
 
 `ifdef   SIM
    always @(posedge clk or negedge rst_n)
     begin
        if(rst_n == 0) cnt <= 0;
        else if(cnt == 32'd100_000)  cnt <= 0;
        else cnt <= cnt + 1;
     end
     
     
     assign  wr_en = (cnt == 32'd20_000);
     assign  rd_en = (cnt == 32'd70_000);
     
`else     
     
     
     always @(posedge clk or negedge rst_n)
     begin
        if(rst_n == 0) cnt <= 0;
        else if(cnt == 32'd500_000_000)  cnt <= 0;
        else cnt <= cnt + 1;
     end
 
 
 assign  wr_en = (cnt == 32'd200_000_000);
 assign  rd_en = (cnt == 32'd400_000_000);    
 
 `endif
 
  parameter data_num = 8'd16;  //the data number of need to be write or read 
 //=========================================
 //write
 always @(posedge clk or negedge rst_n)
 begin
    if(rst_n == 0) wr_addr <= 0;
    else if(rd_wrdata_en_flag[5])  begin
        if(wr_addr == data_num) wr_addr <= 0;  
        else wr_addr <= wr_addr + 1;
      end 
    else   wr_addr <= wr_addr;
 end
 
 
 always @(posedge clk or negedge rst_n)
 begin
    if(rst_n == 0) wr_data <= 0;
    else if(rd_wrdata_en_flag[5])  begin
        if(wr_data == data_num) wr_data <= 0;  
        else wr_data <= wr_data + 1;
      end 
    else   wr_data <= wr_data;
 end
     
 
 always @(posedge clk or negedge rst_n)
 begin
    if(rst_n == 0) wr_cnt <= 0;
    else if(rd_wrdata_en_flag[5])  begin
        if(wr_cnt == data_num) wr_cnt <= 0;  
        else wr_cnt <= wr_cnt + 1;
      end 
    else   wr_cnt <= wr_cnt;
 end
 
  
 always @(posedge clk or negedge rst_n)
 begin
    if(rst_n == 0) wr_flag <= 0;
    else if(wr_en) wr_flag <= 1;
    else if(rd_wrdata_en_flag[5])  begin
        if(wr_cnt == data_num) wr_flag <= 0;  
        else wr_flag <= 1;
      end 
    else   wr_flag <= wr_flag;
 end 
 
 
 //====================================
 //read
 
  always @(posedge clk or negedge rst_n)
 begin
    if(rst_n == 0) rd_addr <= 0;
    else if(wr_rddata_en)  begin
        if(rd_addr == data_num) rd_addr <= 0;  
        else rd_addr <= rd_addr + 1;
      end 
    else   rd_addr <= rd_addr;
 end
 
 
// always @(posedge clk or negedge rst_n)
// begin
//    if(rst_n == 0) rd_data <= 0;
//    else if(wr_rddata_en)  begin
//        if(rd_data == 8'D127) rd_data <= 0;  
//        else rd_data <= rd_data + 1;
//      end 
//    else   rd_data <= rd_data;
// end
//     
 
 
  always @(posedge clk or negedge rst_n)
 begin
    if(rst_n == 0) rd_cnt <= 0;
    else if(wr_rddata_en)  begin
        if(rd_cnt == data_num) rd_cnt <= 0;  
        else rd_cnt <= rd_cnt + 1;
      end 
    else   rd_cnt <= rd_cnt;
 end
     
  always @(posedge clk or negedge rst_n)
 begin
    if(rst_n == 0) rd_flag <= 0;
    else if(rd_en) rd_flag <= 1;
    else if(wr_rddata_en)  begin
        if(data_num == 0)  rd_flag <= 0;
        else if(rd_cnt == (data_num-1)) rd_flag <= 0;  
        else rd_flag <= 1;
      end 
    else   rd_flag <= rd_flag;
 end
 
 wire                fifo_empty;
 wire [4:0]      cnt_fifo;
 wire             clr_fifo;
 
 assign  clr_fifo = wr_rddata_en&&(rd_cnt == (data_num-1));
 
 RD_DATA_BUF u_rd_data_buf(
        .aclr(clr_fifo),
        .clock(clk),
        .data(rd_data),
        .rdreq(1'b0),
        .wrreq(wr_rddata_en),
        .empty(fifo_empty),
        .full(),
        .q(),
        .usedw(cnt_fifo)
        );
 

 endmodule 
 
 
View Code
 //======================================
 //  I2C.v
 //   
 //==========================
// `define SIM         //if run modelsim, enable 

    module I2C( 
  
      input            clk,         //sysclk = 50Mhz
      input            rst_n,
      
      input    [1:0] wr_rd_en,   //wr_rd_en[1] = read, wr_rd_en[0] = write
      input            wr_data_flag, //if still have data to write,the flag always is high
      input            rd_data_flag, //if still have data to read,the flag always is high
      input    [7:0]    wr_addr,
      input    [7:0]    wr_data,
      input    [7:0]    rd_addr,
      
      output    [7:0]    rd_data,
      output            rd_wrdata_en,  //read data from eeprom_data.v to write eeprom
      output         wr_rddata_en,  //write the read data from eeprom to eeprom_data.v
        
      output       ee_I2C_CLK,
      inout        ee_I2C_SDA
   );
      
    reg    [1:0]        wr_rd_en_reg1,wr_rd_en_reg2;
    
   reg        [4:0]   state;
  
    parameter IDLE = 5'd0;
    parameter START_1 = 5'd1;
    parameter START_2 = 5'd2;
    parameter START_3 = 5'd3;
    parameter WR_CTL_1 = 5'd4;
    parameter WR_CTL_2 = 5'd5;
    parameter WR_CTL_ACK1 = 5'd6;
    parameter WR_CTL_ACK2 = 5'd7;
    parameter WR_ADDR_1 = 5'd8;    
    parameter WR_ADDR_2 = 5'd9;    
    parameter WR_ADDR_ACK1 = 5'd10;
    parameter WR_ADDR_ACK2 = 5'd11;
    
    parameter WR_DATA_1 = 5'd12;
    parameter WR_DATA_2 = 5'd13;    
    parameter WR_DATA_3 = 5'd14;    
    parameter WR_DATA_ACK1 = 5'd15;
    parameter WR_DATA_ACK2 = 5'd16;
    
    parameter RD_DATA_1 = 5'd17;
    parameter RD_DATA_2 = 5'd18;    
    parameter RD_DATA_ACK1 = 5'd19;    
    parameter RD_DATA_ACK2 = 5'd20;
    
    parameter STOP_1 = 5'd21;
    parameter STOP_2 = 5'd22;
    parameter STOP_3 = 5'd23;  
    parameter WRITE_TIME = 5'd24;     //delay 10ms   
  
   parameter CMD_control = 7'b1010000; //eeprom addr = 3'b000;
   
`ifdef SIM
    parameter delay = 20'd100; 
   parameter delay_10ms = 20'd500;
`else
   parameter delay = 20'd300; 
   parameter delay_10ms = 20'd500000;
`endif  
    
    always @(posedge clk or negedge rst_n) 
   begin
     if(rst_n == 0) begin 
            wr_rd_en_reg2 <= 2'd0;
            wr_rd_en_reg1 <= 2'd0 ;
        end
     else begin
            wr_rd_en_reg2 <= wr_rd_en_reg1;
            wr_rd_en_reg1 <= wr_rd_en ;
        end
   end
    
    reg     [4:0]   num;  //data = 8bit
    reg     [19:0]  delay_cnt; 
    reg    [7:0]      addr_reg;  //reg addr
    reg     [7:0]    data_reg;  //reg data
    reg                wr_flag;   //write flag
    reg                rd_flag;   //read flag
    reg                rd_restart_flag; // read, the next start flag
    reg                dir_sda_flag;  // dir of sda flag
    reg                rd_wrdata_flag; //when write data ,need read data first
    reg                wr_rddata_flag;
    
    reg    [7:0]   rd_data_reg;
    reg                ee_sclk_reg;   
    reg                ee_data_reg;
  
  always @(posedge clk or negedge rst_n) 
   begin
     if(rst_n == 0) begin  
      state <= IDLE;
        num <= 0;
        delay_cnt <= 0;
        addr_reg <= 0;
        data_reg <= 0;
        wr_flag <= 0;
        dir_sda_flag <= 0;
        rd_flag <= 0;
        rd_restart_flag <= 0;
        rd_wrdata_flag <= 0;
        wr_rddata_flag <= 0;
        rd_data_reg <= 0;
        
        ee_sclk_reg <= 1;
        ee_data_reg <= 1;
        
        end
    else begin
        case(state)
            IDLE: begin
             num <= 0;
             delay_cnt <= 0;
             data_reg  <= 0;
             addr_reg <= 0;
             wr_flag <= 0;
             dir_sda_flag <= 0;
             rd_flag <= 0;
             rd_restart_flag <= 0;
             rd_wrdata_flag <= 0;
             wr_rddata_flag <= 0;
             rd_data_reg <= 0;
             
             ee_sclk_reg <= 1;
             ee_data_reg <= 1;
             
             if(wr_rd_en_reg2 == 2'b01) begin   //write
                addr_reg <= wr_addr ;
                wr_flag <= 1;
                rd_flag <= 0;
                state <= START_1;    
                dir_sda_flag <= 1;                
             end
            else if(wr_rd_en_reg2 == 2'b10)  begin   //read
                addr_reg <= rd_addr ;
                wr_flag <= 0;
                rd_flag <= 1;
                state <= START_1;
                dir_sda_flag <= 1;
                rd_data_reg <= 0;                
             end
            else begin
                state <= state;
                
             end
         end
    
    START_1: begin          //reg 
            ee_sclk_reg <= 1;
            ee_data_reg <= 1;
          if(delay_cnt == delay<<1 ) begin
                state <= state + 1;
                delay_cnt <= 0;
             end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
             end
            end
     START_2: begin       //pull down DATA 
            ee_sclk_reg <= 1;
            ee_data_reg <= 0;
          if(delay_cnt == delay ) begin
                state <= state + 1;
                delay_cnt <= 0;
             end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
             end
            end
    START_3: begin         //pull down SCL 
            ee_sclk_reg <= 0;
            ee_data_reg <= 0;
            num <= 7;
          if(delay_cnt == delay ) begin                            
                delay_cnt <= 0;
                
                if(rd_restart_flag) begin 
                        data_reg <= {CMD_control,1'b1};
                        state <= WR_CTL_1;    
                                       
                  end
                else if((wr_flag ==1)&&(rd_flag == 0)) begin
                        data_reg <= {CMD_control,1'b0};
                        state <= WR_CTL_1;
                    end    
            else if((wr_flag == 0)&&(rd_flag == 1)) begin
                        data_reg <= {CMD_control,1'b0};
                        state <= WR_CTL_1;
                    end         
                else begin
                        data_reg <= 0;  
                        state <= IDLE;
                    end
             end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
             end
            end
     WR_CTL_1 : begin   //write CMD,change data at middle of SCL low time
            ee_sclk_reg <= 0;    
            
            if(delay_cnt == delay>>1) ee_data_reg <= data_reg[num];
            else  ee_data_reg <= ee_data_reg;
            
            if(delay_cnt == delay) begin  
                state <= state + 1;
                delay_cnt <= 0;
                end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
                end
            end
        WR_CTL_2: begin  //write CMD,write data
            ee_sclk_reg <= 1;
            ee_data_reg <= ee_data_reg;
            if(delay_cnt == delay) begin  
                if(num == 0) begin                     
                    state <= state + 1;
                    delay_cnt <= 0;                         
                  end
               else begin 
                   state <= WR_CTL_1;
                    delay_cnt <= 0;
                   num <= num -1;
                 end
              end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
                end
            end
            
        WR_CTL_ACK1 : begin     //ack
            ee_sclk_reg <= 0;
            ee_data_reg <= 0;
            
            if(delay_cnt == 4)  dir_sda_flag <= 0;  //delay, make sure SDA change in the SCK Low
            else  dir_sda_flag <= dir_sda_flag;
            
            if(delay_cnt == delay) begin
                    state <= state + 1;
                    delay_cnt <= 0;
                  end
                else  begin
                    state <= state ;
                    delay_cnt <= delay_cnt + 1;
             end
         end
        WR_CTL_ACK2 : begin
        
            ee_sclk_reg <= 1;
            if(delay_cnt == delay) begin                    
                    delay_cnt <= 0;
                    if(rd_restart_flag)  begin 
                        state <= RD_DATA_1;
                        delay_cnt <= 0;    
                        num <= 7;
                        rd_restart_flag <= 0;
                    end
                    else begin
                       state <= WR_ADDR_1;    
                        num <= 7;
                    end
                  end
                else  begin
                    state <= state ;
                    delay_cnt <= delay_cnt + 1;
             end
                
            end
            
      WR_ADDR_1: begin   //write addr,change data
          ee_sclk_reg <= 0;    
            
            if(delay_cnt == 4)  dir_sda_flag <= 1;
            else  dir_sda_flag <= dir_sda_flag;
    
            if(delay_cnt == delay>>1) ee_data_reg <= addr_reg[num];
            else  ee_data_reg <= ee_data_reg;
            
            if(delay_cnt == delay) begin  
                state <= state + 1;
                delay_cnt <= 0;
                end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
                end                
            end    
        WR_ADDR_2: begin   //write addr,WRITE data
            ee_sclk_reg <= 1;
            ee_data_reg <= ee_data_reg;
            if(delay_cnt == delay) begin  
                if(num == 0) begin    
                    state <= WR_ADDR_ACK1;
                    delay_cnt <= 0;    
                 end
               else begin 
                   state <= WR_ADDR_1;
                    delay_cnt <= 0;
                   num <= num -1;
                 end
              end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
                end
            end
        
     WR_ADDR_ACK1 : begin
            ee_sclk_reg <= 0;
            ee_data_reg <= 0;
            
            if(delay_cnt == 4)  dir_sda_flag <= 0;
            else  dir_sda_flag <= dir_sda_flag;
            
            if(delay_cnt == delay) begin
                    state <= state + 1;
                    delay_cnt <= 0;
                  end
                else  begin
                    state <= state ;
                    delay_cnt <= delay_cnt + 1;
             end     
       end
   WR_ADDR_ACK2: begin
            ee_sclk_reg <= 1;
            if(delay_cnt == delay) begin
                    delay_cnt <= 0;
                    if((wr_flag ==1)&&(rd_flag == 0))  begin
                        state <= WR_DATA_1 ;
                        num <= 7;
                        end
                    else if((wr_flag ==0)&&(rd_flag == 1))  begin
                        state <= START_1 ;
                        rd_restart_flag <= 1;
                        dir_sda_flag <= 1;
                     end
                    else begin
                        state <= IDLE ;
                    end 
                  end
                else  begin
                    state <= state ;
                    delay_cnt <= delay_cnt + 1;
             end     
       end

    
        WR_DATA_1 : begin
            ee_sclk_reg <= 0;    
            num <= 7 ;
            
            if(delay_cnt == 3)  dir_sda_flag <= 1;
            else  dir_sda_flag <= dir_sda_flag;
            
            if(delay_cnt == 1) rd_wrdata_flag <= 1;
            else rd_wrdata_flag <= 0;
            
            if(delay_cnt == 5) begin
                delay_cnt <= 0 ;
               state <= state + 1;
                data_reg <= wr_data;
                
              end
            else  begin                
                delay_cnt <= delay_cnt + 1 ;
               state <= state;
             end    
        end
        WR_DATA_2 : begin
            ee_sclk_reg <= 0;
            if(delay_cnt == delay>>1) ee_data_reg <= data_reg[num];
            else  ee_data_reg <= ee_data_reg;
            
            if(delay_cnt == delay) begin  
                state <= state + 1;
                delay_cnt <= 0;
                end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
                end        
          end
          
        WR_DATA_3: begin 
            ee_sclk_reg <= 1;
            ee_data_reg <= ee_data_reg;
            if(delay_cnt == delay) begin  
                if(num == 0) begin
                        state <= WR_DATA_ACK1;
                        delay_cnt <= 0; 
                        end            
               else begin 
                   state <= WR_DATA_2;
                    delay_cnt <= 0;
                   num <= num -1;
                 end
              end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
             end    
         end
           
      WR_DATA_ACK1: begin
           ee_sclk_reg <= 0;
            ee_data_reg <= 0;
            
            if(delay_cnt == 4)  dir_sda_flag <= 0;
            else  dir_sda_flag <= dir_sda_flag;
            
            if(delay_cnt == delay) begin
                    state <= state + 1;
                    delay_cnt <= 0;
                  end
                else  begin
                    state <= state ;
                    delay_cnt <= delay_cnt + 1;
             end     
       end
      WR_DATA_ACK2: begin
           ee_sclk_reg <= 1;
            if(delay_cnt == delay) begin
                    delay_cnt <= 0;
                    dir_sda_flag <= 1;
                    
                    if(wr_data_flag)  state <= WR_DATA_1 ;
                    else state <= STOP_1 ;    
                    
                  end
                else  begin
                    state <= state ;
                    delay_cnt <= delay_cnt + 1;
             end     
       end    
    
        
    
         
      RD_DATA_1: begin   //read
             ee_sclk_reg <= 0;
            
             if(delay_cnt == 4)  dir_sda_flag <= 0;
             else  dir_sda_flag <= dir_sda_flag;
            
             if(delay_cnt == delay>>1)     rd_data_reg[num] <= ee_I2C_SDA;
            else  data_reg <= data_reg;
             
             if(delay_cnt == delay) begin  
                state <= state + 1;
                delay_cnt <= 0;
                end
              else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
                end
         end
      RD_DATA_2: begin
             ee_sclk_reg <= 1;            

             if(delay_cnt == delay) begin  
               if(num == 0) begin
                    state <= state + 1;
                    delay_cnt <= 0;
                  end
                 else begin
                   state <= RD_DATA_1;
                    delay_cnt <= 0;
                    num <= num - 1;
                 end
                end
              else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
                end
         end
        RD_DATA_ACK1: begin    //read data  from slave, Notice: the ACK send from Master.    
            ee_sclk_reg <= 0;  
            
            if(delay_cnt == 4)  dir_sda_flag <= 1;
            else  dir_sda_flag <= dir_sda_flag;
                
            if(rd_data_flag) ee_data_reg <= 0;     //if have data need to read, Master must PULL DOWN the SDA             
            else ee_data_reg <= 1;
            
            if(delay_cnt == delay) begin
                    state <= state + 1;
                    delay_cnt <= 0;
                  end
                else  begin
                    state <= state ;
                    delay_cnt <= delay_cnt + 1;
             end     
                
           end
        RD_DATA_ACK2 : begin 
            
           ee_sclk_reg <= 1;
            if(delay_cnt == 2)  wr_rddata_flag <= 1;
            else wr_rddata_flag <= 0;
            
            if(delay_cnt == delay) begin
                    delay_cnt <= 0;
                                        
                    if(rd_data_flag) begin
                        state <= RD_DATA_1 ;
                        num <= 7;
                     end
                    else begin
                        state <= STOP_1 ;    
                        num <= 0;
                     end
                  end
                else  begin
                    state <= state ;
                    delay_cnt <= delay_cnt + 1;
             end      
          end
         
        STOP_1: begin 
            ee_sclk_reg <= 0;    
            ee_data_reg <= 0;
           if(delay_cnt == delay) begin  
                state <= state + 1;
                delay_cnt <= 0;
                end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
                end                
            end        
        STOP_2: begin
            ee_sclk_reg <= 1;    
            ee_data_reg <= 0;
           if(delay_cnt == delay) begin  
                state <= state + 1;
                delay_cnt <= 0;
                end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
                end                
            end
        STOP_3: begin
            ee_sclk_reg <= 1;    
            ee_data_reg <= 1;
           if(delay_cnt == delay) begin  
                if(wr_flag == 1)  begin 
                    state <= state + 1;
                    delay_cnt <= 0;
                    end
                else begin  //read,not need wait.
                    rd_flag <= 0;
                    state <= IDLE; 
                    delay_cnt <= 0;
                 end
                end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
                end                
            end
      WRITE_TIME:  begin  //if write, need wait a lot time to re-satrt.if read, not need wait.
           wr_flag <= 0;
            if(delay_cnt == delay_10ms) begin  
                state <= IDLE;
                delay_cnt <= 0;
                end
            else begin 
                state <= state ;
                delay_cnt <= delay_cnt + 1;
                end                
            end
        default: state <= IDLE;    
     endcase 
    end
  end
 
  
  //----------------------------------
  assign     ee_I2C_CLK = ee_sclk_reg;
  assign     ee_I2C_SDA = dir_sda_flag ? ee_data_reg: 1'bz;
    
  assign     rd_wrdata_en = rd_wrdata_flag;
  assign     wr_rddata_en = wr_rddata_flag;
  
  assign     rd_data = rd_data_reg;
  
   
  endmodule 
  
  
  
  
  
  
  
  
  
View Code
// megafunction wizard: %FIFO%
// GENERATION: STANDARD
// VERSION: WM1.0
// MODULE: scfifo 

// ============================================================
// File Name: RD_DATA_BUF.v
// Megafunction Name(s):
//             scfifo
//
// Simulation Library Files(s):
//             altera_mf
// ============================================================
// ************************************************************
// THIS IS A WIZARD-GENERATED FILE. DO NOT EDIT THIS FILE!
//
// 16.0.0 Build 211 04/27/2016 SJ Standard Edition
// ************************************************************


//Copyright (C) 1991-2016 Altera Corporation. All rights reserved.
//Your use of Altera Corporation's design tools, logic functions 
//and other software and tools, and its AMPP partner logic 
//functions, and any output files from any of the foregoing 
//(including device programming or simulation files), and any 
//associated documentation or information are expressly subject 
//to the terms and conditions of the Altera Program License 
//Subscription Agreement, the Altera Quartus Prime License Agreement,
//the Altera MegaCore Function License Agreement, or other 
//applicable license agreement, including, without limitation, 
//that your use is for the sole purpose of programming logic 
//devices manufactured by Altera and sold by Altera or its 
//authorized distributors.  Please refer to the applicable 
//agreement for further details.


// synopsys translate_off
`timescale 1 ps / 1 ps
// synopsys translate_on
module RD_DATA_BUF (
    aclr,
    clock,
    data,
    rdreq,
    wrreq,
    empty,
    full,
    q,
    usedw);

    input      aclr;
    input      clock;
    input    [7:0]  data;
    input      rdreq;
    input      wrreq;
    output      empty;
    output      full;
    output    [7:0]  q;
    output    [4:0]  usedw;

    wire  sub_wire0;
    wire  sub_wire1;
    wire [7:0] sub_wire2;
    wire [4:0] sub_wire3;
    wire  empty = sub_wire0;
    wire  full = sub_wire1;
    wire [7:0] q = sub_wire2[7:0];
    wire [4:0] usedw = sub_wire3[4:0];

    scfifo    scfifo_component (
                .aclr (aclr),
                .clock (clock),
                .data (data),
                .rdreq (rdreq),
                .wrreq (wrreq),
                .empty (sub_wire0),
                .full (sub_wire1),
                .q (sub_wire2),
                .usedw (sub_wire3),
                .almost_empty (),
                .almost_full (),
                .eccstatus (),
                .sclr ());
    defparam
        scfifo_component.add_ram_output_register = "OFF",
        scfifo_component.intended_device_family = "Cyclone IV E",
        scfifo_component.lpm_numwords = 32,
        scfifo_component.lpm_showahead = "OFF",
        scfifo_component.lpm_type = "scfifo",
        scfifo_component.lpm_width = 8,
        scfifo_component.lpm_widthu = 5,
        scfifo_component.overflow_checking = "ON",
        scfifo_component.underflow_checking = "ON",
        scfifo_component.use_eab = "ON";


endmodule

// ============================================================
// CNX file retrieval info
// ============================================================
// Retrieval info: PRIVATE: AlmostEmpty NUMERIC "0"
// Retrieval info: PRIVATE: AlmostEmptyThr NUMERIC "-1"
// Retrieval info: PRIVATE: AlmostFull NUMERIC "0"
// Retrieval info: PRIVATE: AlmostFullThr NUMERIC "-1"
// Retrieval info: PRIVATE: CLOCKS_ARE_SYNCHRONIZED NUMERIC "1"
// Retrieval info: PRIVATE: Clock NUMERIC "0"
// Retrieval info: PRIVATE: Depth NUMERIC "32"
// Retrieval info: PRIVATE: Empty NUMERIC "1"
// Retrieval info: PRIVATE: Full NUMERIC "1"
// Retrieval info: PRIVATE: INTENDED_DEVICE_FAMILY STRING "Cyclone IV E"
// Retrieval info: PRIVATE: LE_BasedFIFO NUMERIC "0"
// Retrieval info: PRIVATE: LegacyRREQ NUMERIC "1"
// Retrieval info: PRIVATE: MAX_DEPTH_BY_9 NUMERIC "0"
// Retrieval info: PRIVATE: OVERFLOW_CHECKING NUMERIC "0"
// Retrieval info: PRIVATE: Optimize NUMERIC "2"
// Retrieval info: PRIVATE: RAM_BLOCK_TYPE NUMERIC "0"
// Retrieval info: PRIVATE: SYNTH_WRAPPER_GEN_POSTFIX STRING "0"
// Retrieval info: PRIVATE: UNDERFLOW_CHECKING NUMERIC "0"
// Retrieval info: PRIVATE: UsedW NUMERIC "1"
// Retrieval info: PRIVATE: Width NUMERIC "8"
// Retrieval info: PRIVATE: dc_aclr NUMERIC "0"
// Retrieval info: PRIVATE: diff_widths NUMERIC "0"
// Retrieval info: PRIVATE: msb_usedw NUMERIC "0"
// Retrieval info: PRIVATE: output_width NUMERIC "8"
// Retrieval info: PRIVATE: rsEmpty NUMERIC "1"
// Retrieval info: PRIVATE: rsFull NUMERIC "0"
// Retrieval info: PRIVATE: rsUsedW NUMERIC "0"
// Retrieval info: PRIVATE: sc_aclr NUMERIC "1"
// Retrieval info: PRIVATE: sc_sclr NUMERIC "0"
// Retrieval info: PRIVATE: wsEmpty NUMERIC "0"
// Retrieval info: PRIVATE: wsFull NUMERIC "1"
// Retrieval info: PRIVATE: wsUsedW NUMERIC "0"
// Retrieval info: LIBRARY: altera_mf altera_mf.altera_mf_components.all
// Retrieval info: CONSTANT: ADD_RAM_OUTPUT_REGISTER STRING "OFF"
// Retrieval info: CONSTANT: INTENDED_DEVICE_FAMILY STRING "Cyclone IV E"
// Retrieval info: CONSTANT: LPM_NUMWORDS NUMERIC "32"
// Retrieval info: CONSTANT: LPM_SHOWAHEAD STRING "OFF"
// Retrieval info: CONSTANT: LPM_TYPE STRING "scfifo"
// Retrieval info: CONSTANT: LPM_WIDTH NUMERIC "8"
// Retrieval info: CONSTANT: LPM_WIDTHU NUMERIC "5"
// Retrieval info: CONSTANT: OVERFLOW_CHECKING STRING "ON"
// Retrieval info: CONSTANT: UNDERFLOW_CHECKING STRING "ON"
// Retrieval info: CONSTANT: USE_EAB STRING "ON"
// Retrieval info: USED_PORT: aclr 0 0 0 0 INPUT NODEFVAL "aclr"
// Retrieval info: USED_PORT: clock 0 0 0 0 INPUT NODEFVAL "clock"
// Retrieval info: USED_PORT: data 0 0 8 0 INPUT NODEFVAL "data[7..0]"
// Retrieval info: USED_PORT: empty 0 0 0 0 OUTPUT NODEFVAL "empty"
// Retrieval info: USED_PORT: full 0 0 0 0 OUTPUT NODEFVAL "full"
// Retrieval info: USED_PORT: q 0 0 8 0 OUTPUT NODEFVAL "q[7..0]"
// Retrieval info: USED_PORT: rdreq 0 0 0 0 INPUT NODEFVAL "rdreq"
// Retrieval info: USED_PORT: usedw 0 0 5 0 OUTPUT NODEFVAL "usedw[4..0]"
// Retrieval info: USED_PORT: wrreq 0 0 0 0 INPUT NODEFVAL "wrreq"
// Retrieval info: CONNECT: @aclr 0 0 0 0 aclr 0 0 0 0
// Retrieval info: CONNECT: @clock 0 0 0 0 clock 0 0 0 0
// Retrieval info: CONNECT: @data 0 0 8 0 data 0 0 8 0
// Retrieval info: CONNECT: @rdreq 0 0 0 0 rdreq 0 0 0 0
// Retrieval info: CONNECT: @wrreq 0 0 0 0 wrreq 0 0 0 0
// Retrieval info: CONNECT: empty 0 0 0 0 @empty 0 0 0 0
// Retrieval info: CONNECT: full 0 0 0 0 @full 0 0 0 0
// Retrieval info: CONNECT: q 0 0 8 0 @q 0 0 8 0
// Retrieval info: CONNECT: usedw 0 0 5 0 @usedw 0 0 5 0
// Retrieval info: GEN_FILE: TYPE_NORMAL RD_DATA_BUF.v TRUE
// Retrieval info: GEN_FILE: TYPE_NORMAL RD_DATA_BUF.inc FALSE
// Retrieval info: GEN_FILE: TYPE_NORMAL RD_DATA_BUF.cmp FALSE
// Retrieval info: GEN_FILE: TYPE_NORMAL RD_DATA_BUF.bsf FALSE
// Retrieval info: GEN_FILE: TYPE_NORMAL RD_DATA_BUF_inst.v FALSE
// Retrieval info: GEN_FILE: TYPE_NORMAL RD_DATA_BUF_bb.v TRUE
// Retrieval info: LIB_FILE: altera_mf
View Code
TB:
`timescale 1 ps/1 ps

  module  EEPROM_TB;
  reg            clk;
  reg            rst_n;
  
  wire       ee_I2C_CLK;
  wire       ee_I2C_SDA;

    
    EEPROM u_EEPROM(
        .clk(clk),
        .rst_n(rst_n),
        
        .EEPROM_SCK(ee_I2C_CLK),
        .EEPROM_SDA(ee_I2C_SDA)
     
     );

    parameter T = 20000;
    
    always #(T/2)  clk = ~clk;
     
    initial 
     begin
        clk = 0;
        rst_n = 0;
        
        $stop;

        #(500*T)  rst_n = 1; 
    end
    
 endmodule 


    
    
    
    
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posted @ 2017-11-22 13:12  远航路上ing  阅读(10572)  评论(0编辑  收藏  举报