注：仿真工具为ISE自带simulation

1.读入.txt中的文件

待读入文件为photo.txt，位于所建工程文件夹中。

代码：

integer cnt,i;reg [7:0] mem[31:0];reg [5:0] address;integer fp;initialbegin	fp = $fopen("photo.txt","rb");	address = 0;    while(!$feof(fp))  begin         for(i=0; i<16; i=i+1)  begin            cnt = $fscanf (fp, "%d",mem[address]);            address=address+1;        end    end    $fclose(fp);end

注释：

使用句柄fp定位文件之后操作即可；

代码中i < 16的值原则上可以为任意值，一般小于文件中数据总数就好了，因为有 while(!$feof(fp)) 在控制；

以二进制方式读入的；

待读入数据：

结果图：

另外一种写法

reg [7:0] mem[31:0];initialbegin    $readmemh("photo.txt",mem);end

注：$readmemh和$readmemb分别用来读入源文件为16进制和2进制的文件

结果图：

2.写出.txt文件

代码：

integer fp_write;reg [5:0] write_address;initialbegin	fp_write =  $fopen("output.txt");	write_address = 0;	while(write_address != 32)	begin		$fwrite(fp_write, "%d ", mem[write_address]);		write_address = write_address + 1;		if(write_address%8 == 0) $fwrite(fp_write, "\n");	end	$fclose(fp_write);end

注：

if(write_address%8 == 0) $fwrite(fp_write, "\n"); 为了给文件中加入换行

结果：

整体代码：

`timescale 1 ns / 1 psmodule testbench;reg clk, rst, start;initial begin     clk = 0;    forever #5 clk = ~clk;endinitial begin    rst = 0;	#8 rst = 1;endinitial begin    start = 0;    #502 start = 1;endinteger cnt,i;reg [7:0] mem[31:0];reg [5:0] address;integer fp;initialbegin	fp = $fopen("photo.txt","rb");	address = 0;    while(!$feof(fp))  begin         for(i=0; i<16; i=i+1)  begin            cnt = $fscanf (fp, "%d",mem[address]);            address=address+1;        end    end    $fclose(fp);endinteger fp_write;reg [5:0] write_address;initialbegin	fp_write =  $fopen("output.txt");	write_address = 0;	while(write_address != 32)	begin		$fwrite(fp_write, "%d ", mem[write_address]);		write_address = write_address + 1;		if(write_address%8 == 0) $fwrite(fp_write, "\n");	end	$fclose(fp_write);endendmodule